SlideShare a Scribd company logo
1 of 53
Welcome to the Webinar on
Energy Saving Calculations for
Existing Building Commissioning
 We’ll start the presentation shortly.

 Hover your cursor at the top of your screen to access the WebEx menu bar and open your
 Chat window.

 We will end with an open discussion, but feel free to ask clarifying or technical support
 questions during the presentation through your Chat window.

Gustav Brändström, PE
Angela Vreeland, PE

February 19, 2013
Energy Saving Calculations for
Existing Building Commissioning




Gustav Brändström, PE
Angela Vreeland, PE

February 19, 2013
Agenda


    Agenda
     Introduction
          Why use spreadsheet calculations?
          Trending and Trend Data
          TMY and Bin Data
          Top Energy Saving Measures in EBCx
     AHU Measure
          Optimize Airside Economizer
     Pump Measure
          Install VFD on Hot Water Pump
     Wrap-up
     Questions

Page 3
Introduction


    Why Use Spreadsheet Calculations?
     Customizable for any application
     Can be based on actual building operation
     Applicable to multiple scenarios with little modification
     TRAP: Do not double count savings! Remember to
         include interactions between findings and equipment.
          Scheduling > Controls changes > Retrofits
          Central system > Major equipment > Terminal equipment




Page 4
Introduction


    Why Use Spreadsheet Calculations?
     Most 3rd party tools apply to specific scenarios
          “Square peg in round hole”
          All inputs must be re-entered for each case
     Energy modeling is not economical for analysis of
         individual equipment
          Time-consuming
          Not intent of modeling software




Page 5
Introduction


    Trending and Trend Data
     Trending – brief overview
          The process of capturing time series data on equipment
           operation
          Data is exported from a Building Automation System (BAS)
           or data loggers for spreadsheet analysis
          Data set-up, collection, processing, and analysis are time
           consuming
          Allows us to understand how the equipment operates


         See the Innovation Exchange’s Webinar on Trending titled:
           Using Building Automation Systems as a Cx Tool


Page 6
Introduction


    Trending and Trend Data
     Why use trend data?
          Trend data allows you to identify operational issues you
           wouldn’t find otherwise.
            Functional performance tests and other tools can’t capture all
             modes of operation
          Trend data allows you to more accurately calculate savings




Page 7
Introduction


    TMY and Bin Data
     Energy savings calculations are based on OAT
     Typical Meteorological Year Weather Data
          Normalized weather
            Covers at least 15 year timeframe
            Average and typical, not average
          “Major” cities only
          Get from NREL
            http://www.nrel.gov/rredc/solar_data.html
     Bin Data
          Grouped or “binned” data
          Increments vary depending on system characteristics
             Outdoor temperature is typically put in 5 F bins
          Used in most spreadsheet calculations
Page 8
Introduction


    TMY and Bin Data
     TRICK: AVERAGEIFS() and COUNTIFS() in Excel
          These functions make creating bins out of data super easy!!
          AVERAGEIFS() - Average value of a range, given criteria
          COUNTIFS() - Number of occurrences in a range, given criteria

                          OAT Bins Avg OAT (F) Hours Hours ON
                          60   65     63.7        3     1.5
                          65   70     68.5      2.25   0.75
                          70   75     72.4      3.25   1.25
                          75   80     77.8        2    1.25
                          80   85     82.5      8.25   5.75
                          85   90     85.8      1.25   1.25

         =AVERAGEIFS(Avg Range, CriteriaRange1, Criteria1, CriteriaRange2,Criteria2, …)
         =AVERAGEIFS(OAT Column, OAT Column,">="&BinLL, OAT Column,"<"&BinUL)
Page 9
Agenda


    Agenda
     Introduction
           Why use spreadsheet calculations?
           Trending and Trend Data
           TMY and Bin Data
           Top Energy Saving Measures in EBCx
     AHU Measure
           Optimize Airside Economizer
     Pump Measure
           Install VFD on Hot Water Pump
     Wrap-up
     Questions

Page 10
AHU Measure


    Top Energy Saving Measures in EBCx
                  Key Measure Mix                     % of Total Savings
              Revise control sequence                          21%
            Reduce equipment runtime                           15%
            Optimize airside economizer                        12%
               Add/optimize SAT reset                           8%
                  Add VFD to pump                               6%
                Reduce coil leakage                             4%
            Reduce/reset DSP setpoint                           4%
          Add/optimize optimum start/stop                       3%
             Add/optimize CWST reset                            2%

          Source: A Study on Energy Savings and Measure Cost Effectiveness of
Page 11                            EBCx, PECI, 2009
AHU Measure


    Optimize Airside Economizer
     Four most common high limit control strategies
             Fixed Drybulb Temperature- OAT
             Differential Drybulb Temperature- OAT vs RAT
             Fixed Enthalpy- OAh
              Enthalpy is calculated from drybulb temperature and humidity

             Differential Enthalpy- OAh vs RAh




Page 12                    ???
AHU Measure


    Optimize Airside Economizer
     Economizers malfunction frequently
           Stuck outside damper
           Outside air (OA) flow measuring station error
           Temperature or humidity
            sensor out of calibration




Page 13
AHU Measure


    Optimize Airside Economizer
     Economizer control errors are common
           Incorrect high and/or low limit setpoint
           Incorrect minimum outside air setpoint
           Lockout between economizer and mechanical cooling


     Result in
           A loss of “free cooling” opportunity
           Increased cooling load
           Increased heating load




Page 14
AHU Measure


    Optimize Airside Economizer
     How do we know if something is wrong?
           Calculate the %OA




            where:
            OAT = Outside Air Temperature
            RAT = Return Air Temperature
            MAT = Mixed Air Temperature


           Plot %OA against OAT and look at the pattern


Page 15
- IDEAL PATTERN




                  Economizer
                  Lockout ~ 70°F



Page 16
AHU Measure


    Optimize Airside Economizer
     Why should the high limit setpoint be ~70 F?
           High limit of 71 F in MN was found to be ideal
             Taylor Engineering Research
             Best economizer control strategy is provided for each region
             November 2010 ASHRAE Journal (Vol. 52, No. 11)
           TRAP: Humidity Sensors are Error-Prone
             Avoid enthalpy high limit control
             Iowa Energy Center Research
             http://www.iowaenergycenter.org/wp-
              content/uploads/2012/05/PTR_Humidity_Rev.pdf




Page 17
AHU Measure


    Optimize Airside Economizer Example
     Finding (problem)
           Economizer high limit lockout is 80 F
     Measure (solution)
           Change the lockout to 70 F




Page 18
- HIGH LIMIT TOO HIGH



          Lower the High Limit Setpoint:
          80°F to 70°F




Page 19
AHU Measure


    Optimize Airside Economizer Example
     Spreadsheet Calculation Layout
            Reducing the high limit setpoint will lead to savings whenever
             the outside air damper is open more than it should be
                     1                                     2                                        3

     A        B            C       D      E         F            G        H         I        J           K          L
                                                      Current                                 Proposed
 OAT Dry    OAT                                              OA            OA                        OA             OA
                         AHU On   RAT                                                                                      Savings
 Bulb Bin Dry Bulb                        OA     OA Flow Cooling        Cooling    OA     OA Flow Cooling        Cooling
                                                           Energy        Input                     Energy         Input
     F        F          Hours     F      %        CFM      kBtus         kWh      %        CFM     kBtus          kWh      kWh
   60/64     62.6         321     70.8   67.9%    9,840          0         0      67.9%    9,840         0          0         0
   65/69     68.1         294     71.2   87.7%    12,712         0         0      87.7%    12,712        0          0         0
   70/74     72.5         265     71.6   95.5%    13,847       3,400      340     10.0%    1,450        356        36        304
   75/79     76.9         317     71.6   78.0%    11,307       20,534    2,053    10.0%    1,450        2,633      263      1790
   80/84     82.1         284     72.6   18.2%    2,643        7,688      769     10.0%    1,450        4,218      422       347
   85/89     87.8         152     72.0   10.0%    1,450        3,758      376     10.0%    1,450        3,758      376        0
   90/94     91.9          54     73.0   10.0%    1,450        1,594      159     10.0%    1,450        1,594      159        0
                                                                                                                            2,442
Page 20
AHU Measure


     Optimize Airside Economizer Example
 1
     A      B         C       D      EColumn A- OAT Bins
                                           F     G    H                    I        J       K         L
                                                 Current                             Proposed
OAT Dry    OAT                         5 F Bins        OA        OA                        OA        OA
                    AHU On   RAT
Bulb Bin Dry Bulb                    OA     OA Flow Cooling    Cooling    OA     OA Flow Cooling   Cooling
                                                      Energy    Input                     Energy    Input
     F      F       Hours     F      %Column B- Average OAT for Bin
                                              CFM      kBtus%    kWh               CFM     kBtus     kWh
  60/64    62.6      321     70.8
                                       Obtain from 0TMY Data
                                    67.9%  9,840          0              67.9%    9,840     0         0
  65/69    68.1      294     71.2   87.7% 12,712    0     0              87.7%    12,712    0         0
  70/74    72.5      265     71.6      Use AVERAGEIFS340
                                    95.5% 13,847  3,400                  10.0%    1,450    356       36
  75/79    76.9      317     71.6   78.0%    11,307   20,534    2,053    10.0%    1,450    2,633     263
  80/84    82.1      284     72.6   18.2%    2,643    7,688      769     10.0%    1,450    4,218     422
  85/89    87.8      152     72.0     Column C- Total Hours the AHU operates
                                    10.0%   1,450 3,758 376  10.0% 1,450 3,758                       376
  90/94    91.9       54     73.0   10.0% during Bin
                                            1,450 1,594 159  10.0% 1,450 1,594                       159

                                       Obtain from trends of SF Status or VFD Speed
                                        and OAT
                                       Use COUNTIFS


Page 21
AHU Measure


     Optimize Airside Economizer Example
 1
     A      B         C       D      EColumn D- Average RAT during JBin
                                           F     G    H     I                           K         L
                                                Current                          Proposed
OAT Dry    OAT                         Obtain from trendsOA RAT and OAT
                                                    OA
                                                             of                     OA            OA
                    AHU On   RAT
Bulb Bin Dry Bulb                      OA RAT vs OAT to see OA pattern
                                     OA Plot Flow Cooling Cooling overall OA Flow Cooling      Cooling
                                                  Energy   Input                  Energy        Input
     F      F       Hours     F       
                                      % Use AVERAGEIFS- Filter for when AHU is ON
                                           CFM     kBtus    kWh     %       CFM    kBtus         kWh
  60/64    62.6      321     70.8   67.9%   9,840         0    0      67.9%   9,840     0         0
  65/69    68.1      294     71.2   87.7%   12,712        0    0      87.7%   12,712    0         0
  70/74    72.5      265     71.6   95.5%   13,847   3,400    340     10.0%   1,450    356       36
  75/79    76.9      317     71.6   78.0%   11,307   20,534   2,053   10.0%   1,450    2,633     263
  80/84    82.1      284     72.6   18.2%   2,643    7,688    769     10.0%   1,450    4,218     422
  85/89    87.8      152     72.0   10.0%   1,450    3,758    376     10.0%   1,450    3,758     376
  90/94    91.9       54     73.0   10.0%   1,450    1,594    159     10.0%   1,450    1,594     159




Page 22
AHU Measure


    Optimize Airside Economizer Example
     Spreadsheet Calculation Layout


                     1                                     2                                        3

     A       B             C       D      E         F            G        H         I        J           K          L
                                                      Current                                 Proposed
 OAT Dry    OAT                                              OA            OA                        OA             OA
                         AHU On   RAT                                                                                      Savings
 Bulb Bin Dry Bulb                        OA     OA Flow Cooling        Cooling    OA     OA Flow Cooling        Cooling
                                                           Energy        Input                     Energy         Input
     F       F           Hours     F      %        CFM      kBtus         kWh      %        CFM     kBtus          kWh      kWh
   60/64    62.6          321     70.8   67.9%    9,840          0         0      67.9%    9,840         0          0         0
   65/69    68.1          294     71.2   87.7%    12,712         0         0      87.7%    12,712        0          0         0
   70/74    72.5          265     71.6   95.5%    13,847       3,400      340     10.0%    1,450        356        36        304
   75/79    76.9          317     71.6   78.0%    11,307       20,534    2,053    10.0%    1,450        2,633      263      1790
   80/84    82.1          284     72.6   18.2%    2,643        7,688      769     10.0%    1,450        4,218      422       347
   85/89    87.8          152     72.0   10.0%    1,450        3,758      376     10.0%    1,450        3,758      376        0
   90/94    91.9           54     73.0   10.0%    1,450        1,594      159     10.0%    1,450        1,594      159        0
                                                                                                                            2,442
Page 23
AHU Measure


      Optimize Airside Economizer Example
 2
      A       E         F        G        H       Column E- Average %OA during Bin
                          Current
OAT Dry
                                                   Obtain from trends of MAT, RAT, and
                                 OA        OA
Bulb Bin      OA     OA Flow Cooling    Cooling     OAT
                               Energy    Input     Plot %OA vs OAT to see overall pattern
      F       %        CFM      kBtus     kWh
                                                   Use AVERAGEIFS- Filter for when AHU
     60/64   67.9%    9,840      0         0
     65/69   87.7%    12,712     0         0
                                                    is ON
     70/74   95.5%    13,847   3,400      340
     75/79   78.0%    11,307   20,534    2,053
     80/84   18.2%    2,643    7,688      769
     85/89   10.0%    1,450    3,758      376
     90/94   10.0%    1,450    1,594      159




Page 24
AHU Measure


      Optimize Airside Economizer Example
 2
      A       E         F        G        H       Column F- OA Flow
                          Current
OAT Dry
                                                   Calculated using equation below
                                 OA        OA
Bulb Bin      OA     OA Flow Cooling    Cooling    SF Speed must be accounted for with
                               Energy    Input      variable volume AHUs
      F       %        CFM      kBtus     kWh
     60/64   67.9%    9,840      0         0
     65/69   87.7%    12,712     0         0
     70/74   95.5%    13,847   3,400      340
                                                  Column G- Cooling Energy
     75/79   78.0%    11,307   20,534    2,053
     80/84   18.2%    2,643    7,688      769      Energy required to cool OA
     85/89   10.0%    1,450    3,758      376      Calculated using equation below
     90/94   10.0%    1,450    1,594      159




Page 25
AHU Measure


      Optimize Airside Economizer Example
 2
      A       E         F        G        H       Column H- Cooling Input
                          Current
OAT Dry
                                                   Calculated using equation below
                                 OA        OA
Bulb Bin      OA     OA Flow Cooling    Cooling
                               Energy    Input
      F       %        CFM      kBtus     kWh
     60/64   67.9%    9,840      0         0
     65/69   87.7%    12,712     0         0
     70/74   95.5%    13,847   3,400      340
     75/79   78.0%    11,307   20,534    2,053
     80/84   18.2%    2,643    7,688      769
     85/89   10.0%    1,450    3,758      376
     90/94   10.0%    1,450    1,594      159




Page 26
AHU Measure


    Optimize Airside Economizer Example
     Spreadsheet Calculation Layout


                     1                                     2                                        3

     A       B             C       D      E         F            G        H         I        J           K          L
                                                      Current                                 Proposed
 OAT Dry    OAT                                              OA            OA                        OA             OA
                         AHU On   RAT                                                                                      Savings
 Bulb Bin Dry Bulb                        OA     OA Flow Cooling        Cooling    OA     OA Flow Cooling        Cooling
                                                           Energy        Input                     Energy         Input
     F       F           Hours     F      %        CFM      kBtus         kWh      %        CFM     kBtus          kWh      kWh
   60/64    62.6          321     70.8   67.9%    9,840          0         0      67.9%    9,840         0          0         0
   65/69    68.1          294     71.2   87.7%    12,712         0         0      87.7%    12,712        0          0         0
   70/74    72.5          265     71.6   95.5%    13,847       3,400      340     10.0%    1,450        356        36        304
   75/79    76.9          317     71.6   78.0%    11,307       20,534    2,053    10.0%    1,450        2,633      263      1790
   80/84    82.1          284     72.6   18.2%    2,643        7,688      769     10.0%    1,450        4,218      422       347
   85/89    87.8          152     72.0   10.0%    1,450        3,758      376     10.0%    1,450        3,758      376        0
   90/94    91.9           54     73.0   10.0%    1,450        1,594      159     10.0%    1,450        1,594      159        0
                                                                                                                            2,442
Page 27
AHU Measure


      Optimize Airside Economizer Example
  3
      A      I        J       K         L      Columns I thru L
                       Proposed
OAT Dry
                                                Repeat the same analysis for
                              OA        OA
Bulb Bin    OA     OA Flow Cooling   Cooling     Proposed Scenario
                            Energy    Input     Above 70 F, the %OA will drop to
      F     %        CFM     kBtus     kWh
                                                 minimum position
  60/64    67.9%    9,840     0         0
  65/69    87.7%    12,712    0         0       Based on data at low OATs, the
  70/74    10.0%    1,450    356       36        minimum %OA is 10%
  75/79    10.0%    1,450    2,633     263
  80/84    10.0%    1,450    4,218     422
  85/89    10.0%    1,450    3,758     376
  90/94    10.0%    1,450    1,594     159




Page 28
AHU Measure


    Optimize Airside Economizer Example
     A        B        C       D      E         F        G        H         I        J       K          L
                                                  Current                             Proposed
 OAT Dry    OAT                                          OA        OA                        OA         OA
                     AHU On   RAT                                                                              Savings
 Bulb Bin Dry Bulb                    OA     OA Flow Cooling    Cooling    OA     OA Flow Cooling    Cooling
                                                       Energy    Input                     Energy     Input
     F        F      Hours     F      %        CFM      kBtus     kWh      %        CFM     kBtus      kWh      kWh
   60/64     62.6     321     70.8   67.9%    9,840      0         0      67.9%    9,840     0          0         0
   65/69     68.1     294     71.2   87.7%    12,712     0         0      87.7%    12,712    0          0         0
   70/74     72.5     265     71.6   95.5%    13,847   3,400      340     10.0%    1,450    356        36        304
   75/79     76.9     317     71.6   78.0%    11,307   20,534    2,053    10.0%    1,450    2,633      263      1790
   80/84     82.1     284     72.6   18.2%    2,643    7,688      769     10.0%    1,450    4,218      422       347
   85/89     87.8     152     72.0   10.0%    1,450    3,758      376     10.0%    1,450    3,758      376        0
   90/94     91.9      54     73.0   10.0%    1,450    1,594      159     10.0%    1,450    1,594      159        0
                                                                                                                2,442



     Savings
            2,442 kWh annually or $170 at 7¢/kWh
            ~10% of energy used to cool OA
            No cost to implement
Page 29
AHU Measure


    Optimize Airside Economizer
     Summary
           Economizers malfunction often, but fixing them is typically
            very easy and cost-effective


     Additional considerations….
           Sometimes fixing the issue leads to more energy use
           An AHU may economize at OATs as low as 20 or 30 F
           The fewer sensors the economizer relies on, the better




Page 30
Agenda


    Agenda
     Introduction
           Why use spreadsheet calculations?
           Trending and Trend Data
           TMY and Bin Data
           Top Energy Saving Measures in EBCx
     AHU Measure
           Optimize Airside Economizer
     Pump Measure
           Install VFD on Hot Water Pump
     Wrap-up
     Questions

Page 31
Pump Measure


    Top Energy Saving Measures in EBCx
                  Key Measure Mix                     % of Total Savings
              Revise control sequence                          21%
            Reduce equipment runtime                           15%
            Optimize airside economizer                        12%
               Add/optimize SAT reset                           8%
                  Add VFD to pump                               6%
                Reduce coil leakage                             4%
            Reduce/reset DSP setpoint                           4%
          Add/optimize optimum start/stop                       3%
             Add/optimize CWST reset                            2%

          Source: A Study on Energy Savings and Measure Cost Effectiveness of
Page 32                            EBCx, PECI, 2009
Pump Measure


    Install VFD on Hot Water Pump
     Constant volume pumping is common in existing
      buildings.
     Hot water loops come in many variants; primary,
      primary/secondary, primary/tertiary, etc.
     Energy savings from reducing the pump speed
     Opportunities exist when the
           drop in temperature is low




Page 33
TRICK: Plot HW dT vs OAT. Example of low temperature drop




                                                            Design Loop dT = 48°F




Page 34
Pump Measure


    Install VFD on Hot Water Pump
     Constant volume pumping is common in existing
      buildings.
     Hot water loops come in many variants; primary,
      primary/secondary, primary/tertiary, etc.
     Energy savings from reducing the pump speed
     Opportunities exist when the
           drop in temperature is low, and/or
           use in the AHUs are low.




Page 35
TRICK: Plot # of AHUs heating vs OAT. Example of Low use of heating at the AHUs




Page 36
Pump Measure


    Install VFD on Hot Water Pump
     Example
           Finding (problem)
              Secondary Hot Water Loop Pump runs excessively
           Measure (solution)
             Install VFD on 40hp Pump, close off three way valves, and install
              differential pressure sensor




Page 37
Pump Measure


    Install VFD on Hot Water Pump
     Calculation Layout

            1
                                                    2
                                                                                        3

                                           % of Total Flow                 %Req.         Energy Use
                  Bin  11.8% 11.3% 7.0%    13.1% 5.5% 15.6% 14.8% 20.9%    Flow      Current Proposed
  OAT     Bin    Hours AHU-1 AHU-2 AHU-3   AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%)    (kWh)      (kWh)
 -20       -10    248  100%   59%  100%     63%      58%   64% 89%  77%       76%     6,994      4,061
 -10        0     309  100%   62%  100%     63%      60%   55% 73%  66%       70%     8,714      4,328
  0         10    436  100%   68%  100%     54%      62%   52% 68%  48%       65%     12,295     5,226
  10        20    696  100%   48%  100%     44%      45%   40% 48%  36%       53%     19,627     5,600
  20        30    1074 100%   27%  100%     28%      27%   31% 27%  15%       39%     30,287     4,622
  30        40    1224 100%   18%  100%      0%      10%   20% 3%   8%        30%     34,517     3,107
  40        50    1114 100%   8%   100%      0%       3%   14% 0%   7%        30%     31,415     2,827
  50        60    1135 100%   0%   100%      0%       0%   9%  0%   3%        30%     32,007     2,881
  60        70    1157  0%    0%    0%       0%       0%   0%  0%   0%        30%     32,627     2,936
                                                                                      208,483     35,588
                                                                                     Savings     172,895
Page 38
Pump Measure


    Install VFD on Hot Water Pump
     Calculation of OAT bins

            1


                                           % of Total Flow                 %Req.         Energy Use
                  Bin  11.8% 11.3% 7.0%    13.1% 5.5% 15.6% 14.8% 20.9%    Flow      Current Proposed
  OAT     Bin    Hours AHU-1 AHU-2 AHU-3   AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%)    (kWh)      (kWh)
 -20       -10    248  100%   59%  100%     63%      58%   64% 89%  77%       76%     6,994      4,061
 -10        0     309  100%   62%  100%     63%      60%   55% 73%  66%       70%     8,714      4,328
  0         10    436  100%   68%  100%     54%      62%   52% 68%  48%       65%     12,295     5,226
  10        20    696  100%   48%  100%     44%      45%   40% 48%  36%       53%     19,627     5,600
  20        30    1074 100%   27%  100%     28%      27%   31% 27%  15%       39%     30,287     4,622
  30        40    1224 100%   18%  100%      0%      10%   20% 3%   8%        30%     34,517     3,107
  40        50    1114 100%   8%   100%      0%       3%   14% 0%   7%        30%     31,415     2,827
  50        60    1135 100%   0%   100%      0%       0%   9%  0%   3%        30%     32,007     2,881
  60        70    1157  0%    0%    0%       0%       0%   0%  0%   0%        30%     32,627     2,936
                                                                                      208,483     35,588
                                                                                     Savings     172,895
Page 39
Pump Measure


    Install VFD on Hot Water Pump
     Calculation of AHU heating use
            % of total loop flow through each AHU

                                                    2

                                           % of Total Flow                 %Req.         Energy Use
                  Bin  11.8% 11.3% 7.0%    13.1% 5.5% 15.6% 14.8% 20.9%    Flow      Current Proposed
  OAT     Bin    Hours AHU-1 AHU-2 AHU-3   AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%)    (kWh)      (kWh)
 -20       -10    248  100%   59%  100%     63%      58%   64% 89%  77%       76%     6,994      4,061
 -10        0     309  100%   62%  100%     63%      60%   55% 73%  66%       70%     8,714      4,328
  0         10    436  100%   68%  100%     54%      62%   52% 68%  48%       65%     12,295     5,226
  10        20    696  100%   48%  100%     44%      45%   40% 48%  36%       53%     19,627     5,600
  20        30    1074 100%   27%  100%     28%      27%   31% 27%  15%       39%     30,287     4,622
  30        40    1224 100%   18%  100%      0%      10%   20% 3%   8%        30%     34,517     3,107
  40        50    1114 100%   8%   100%      0%       3%   14% 0%   7%        30%     31,415     2,827
  50        60    1135 100%   0%   100%      0%       0%   9%  0%   3%        30%     32,007     2,881
  60        70    1157  0%    0%    0%       0%       0%   0%  0%   0%        30%     32,627     2,936
                                                                                      208,483     35,588
                                                                                     Savings     172,895
Page 40
Pump Measure


    Install VFD on Hot Water Pump
     Calculation of AHU heating use
     TRAP: Do not assume linear load
     TRICK: AVERAGEIFS()                           2

                                           % of Total Flow                 %Req.         Energy Use
                  Bin  11.8% 11.3% 7.0%    13.1% 5.5% 15.6% 14.8% 20.9%    Flow      Current Proposed
  OAT     Bin    Hours AHU-1 AHU-2 AHU-3   AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%)    (kWh)      (kWh)
 -20       -10    248  100%   59%  100%     63%      58%   64% 89%  77%       76%     6,994      4,061
 -10        0     309  100%   62%  100%     63%      60%   55% 73%  66%       70%     8,714      4,328
  0         10    436  100%   68%  100%     54%      62%   52% 68%  48%       65%     12,295     5,226
  10        20    696  100%   48%  100%     44%      45%   40% 48%  36%       53%     19,627     5,600
  20        30    1074 100%   27%  100%     28%      27%   31% 27%  15%       39%     30,287     4,622
  30        40    1224 100%   18%  100%      0%      10%   20% 3%   8%        30%     34,517     3,107
  40        50    1114 100%   8%   100%      0%       3%   14% 0%   7%        30%     31,415     2,827
  50        60    1135 100%   0%   100%      0%       0%   9%  0%   3%        30%     32,007     2,881
  60        70    1157  0%    0%    0%       0%       0%   0%  0%   0%        30%     32,627     2,936
                                                                                      208,483     35,588
                                                                                     Savings     172,895
Page 41
Pump Measure


    Install VFD on Hot Water Pump
     Calculation of AHU heating use – Three-way
           valves
                                                    2

                                           % of Total Flow                 %Req.         Energy Use
                  Bin  11.8% 11.3% 7.0%    13.1% 5.5% 15.6% 14.8% 20.9%    Flow      Current Proposed
  OAT     Bin    Hours AHU-1 AHU-2 AHU-3   AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%)    (kWh)      (kWh)
 -20       -10    248  100%   59%  100%     63%      58%   64% 89%  77%       76%     6,994      4,061
 -10        0     309  100%   62%  100%     63%      60%   55% 73%  66%       70%     8,714      4,328
  0         10    436  100%   68%  100%     54%      62%   52% 68%  48%       65%     12,295     5,226
  10        20    696  100%   48%  100%     44%      45%   40% 48%  36%       53%     19,627     5,600
  20        30    1074 100%   27%  100%     28%      27%   31% 27%  15%       39%     30,287     4,622
  30        40    1224 100%   18%  100%      0%      10%   20% 3%   8%        30%     34,517     3,107
  40        50    1114 100%   8%   100%      0%       3%   14% 0%   7%        30%     31,415     2,827
  50        60    1135 100%   0%   100%      0%       0%   9%  0%   3%        30%     32,007     2,881
  60        70    1157  0%    0%    0%       0%       0%   0%  0%   0%        30%     32,627     2,936
                                                                                      208,483     35,588
                                                                                     Savings     172,895
Page 42
Pump Measure


    Install VFD on Hot Water Pump
     Calculation of total heating use
     TRAP: Do not assume 30% minimum flow (as I did)
                                                    2

                                           % of Total Flow                 %Req.         Energy Use
                  Bin  11.8% 11.3% 7.0%    13.1% 5.5% 15.6% 14.8% 20.9%    Flow      Current Proposed
  OAT     Bin    Hours AHU-1 AHU-2 AHU-3   AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%)    (kWh)      (kWh)
 -20       -10    248  100%   59%  100%     63%      58%   64% 89%  77%       76%     6,994      4,061
 -10        0     309  100%   62%  100%     63%      60%   55% 73%  66%       70%     8,714      4,328
  0         10    436  100%   68%  100%     54%      62%   52% 68%  48%       65%     12,295     5,226
  10        20    696  100%   48%  100%     44%      45%   40% 48%  36%       53%     19,627     5,600
  20        30    1074 100%   27%  100%     28%      27%   31% 27%  15%       39%     30,287     4,622
  30        40    1224 100%   18%  100%      0%      10%   20% 3%   8%        30%     34,517     3,107
  40        50    1114 100%   8%   100%      0%       3%   14% 0%   7%        30%     31,415     2,827
  50        60    1135 100%   0%   100%      0%       0%   9%  0%   3%        30%     32,007     2,881
  60        70    1157  0%    0%    0%       0%       0%   0%  0%   0%        30%     32,627     2,936
                                                                                      208,483     35,588
                                                                                     Savings     172,895
Page 43
Pump Measure


    Install VFD on Hot Water Pump
     Calculation of total heating use


                                                                                        3

                                           % of Total Flow                 %Req.         Energy Use
                  Bin  11.8% 11.3% 7.0%    13.1% 5.5% 15.6% 14.8% 20.9%    Flow      Current Proposed
  OAT     Bin    Hours AHU-1 AHU-2 AHU-3   AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%)    (kWh)      (kWh)
 -20       -10    248  100%   59%  100%     63%      58%   64% 89%  77%       76%     6,994      4,061
 -10        0     309  100%   62%  100%     63%      60%   55% 73%  66%       70%     8,714      4,328
  0         10    436  100%   68%  100%     54%      62%   52% 68%  48%       65%     12,295     5,226
  10        20    696  100%   48%  100%     44%      45%   40% 48%  36%       53%     19,627     5,600
  20        30    1074 100%   27%  100%     28%      27%   31% 27%  15%       39%     30,287     4,622
  30        40    1224 100%   18%  100%      0%      10%   20% 3%   8%        30%     34,517     3,107
  40        50    1114 100%   8%   100%      0%       3%   14% 0%   7%        30%     31,415     2,827
  50        60    1135 100%   0%   100%      0%       0%   9%  0%   3%        30%     32,007     2,881
  60        70    1157  0%    0%    0%       0%       0%   0%  0%   0%        30%     32,627     2,936
                                                                                      208,483     35,588
                                                                                     Savings     172,895
Page 44
Pump Measure


    Install VFD on Hot Water Pump
     Calculation of current (100% flow) vs proposed
           pump energy use

                                                                                        3

                                           % of Total Flow                 %Req.         Energy Use
                  Bin  11.8% 11.3% 7.0%    13.1% 5.5% 15.6% 14.8% 20.9%    Flow      Current Proposed
  OAT     Bin    Hours AHU-1 AHU-2 AHU-3   AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%)    (kWh)      (kWh)
 -20       -10    248  100%   59%  100%     63%      58%   64% 89%  77%       76%     6,994      4,061
 -10        0     309  100%   62%  100%     63%      60%   55% 73%  66%       70%     8,714      4,328
  0         10    436  100%   68%  100%     54%      62%   52% 68%  48%       65%     12,295     5,226
  10        20    696  100%   48%  100%     44%      45%   40% 48%  36%       53%     19,627     5,600
  20        30    1074 100%   27%  100%     28%      27%   31% 27%  15%       39%     30,287     4,622
  30        40    1224 100%   18%  100%      0%      10%   20% 3%   8%        30%     34,517     3,107
  40        50    1114 100%   8%   100%      0%       3%   14% 0%   7%        30%     31,415     2,827
  50        60    1135 100%   0%   100%      0%       0%   9%  0%   3%        30%     32,007     2,881
  60        70    1157  0%    0%    0%       0%       0%   0%  0%   0%        30%     32,627     2,936
                                                                                      208,483     35,588
                                                                                     Savings     172,895
Page 45
Pump Measure


    Install VFD on Hot Water Pump
     Saves 172,895 kWh annually, or $12,100 at 7¢/kWh.
           83% of the current pump energy use saved!

                                                                                        3

                                           % of Total Flow                 %Req.         Energy Use
                  Bin  11.8% 11.3% 7.0%    13.1% 5.5% 15.6% 14.8% 20.9%    Flow      Current Proposed
  OAT     Bin    Hours AHU-1 AHU-2 AHU-3   AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%)    (kWh)      (kWh)
 -20       -10    248  100%   59%  100%     63%      58%   64% 89%  77%       76%     6,994      4,061
 -10        0     309  100%   62%  100%     63%      60%   55% 73%  66%       70%     8,714      4,328
  0         10    436  100%   68%  100%     54%      62%   52% 68%  48%       65%     12,295     5,226
  10        20    696  100%   48%  100%     44%      45%   40% 48%  36%       53%     19,627     5,600
  20        30    1074 100%   27%  100%     28%      27%   31% 27%  15%       39%     30,287     4,622
  30        40    1224 100%   18%  100%      0%      10%   20% 3%   8%        30%     34,517     3,107
  40        50    1114 100%   8%   100%      0%       3%   14% 0%   7%        30%     31,415     2,827
  50        60    1135 100%   0%   100%      0%       0%   9%  0%   3%        30%     32,007     2,881
  60        70    1157  0%    0%    0%       0%       0%   0%  0%   0%        30%     32,627     2,936
                                                                                      208,483     35,588
                                                                                     Savings     172,895
Page 46
Pump Measure


    Install VFD on Hot Water Pump
     Summary of Measure
           Keep the pump running at as low of a speed as possible
           TRICK: In conjunction with adding a VFD, look at the scheduling.
           TRAP: If there are different modes of operation, account for them!
            (Morning Warm-up, freeze protection, etc.)
           SAVE LOTS OF ENERGY!
             Implementation cost $29,000 (incl. commissioning)
             Energy Savings $12,100
             Simple Payback 2.4 years




Page 47
Agenda


    Agenda
     Introduction
           Why use spreadsheet calculations?
           Trending and Trend Data
           TMY and Bin Data
           Top Energy Saving Measures in EBCx
     AHU Measure
           Optimize Airside Economizer
     Pump Measure
           Install VFD on Hot Water Pump
     Wrap-up
     Questions

Page 48
Introduction


    Target High Energy Savings Measures
                                         Key Measure Mix                   % of Total
                                                                            Savings
                                     Revise control sequence                   21%
               TRICKs
                                    Reduce equipment runtime                   15%
   Focus on:
    • Large equipment (high         Optimize airside economizer                12%
      horsepower, tonnage, etc)       Add/optimize SAT reset                   8%
     • Equipment that runs a lot         Add VFD to pump                       6%
                                        Reduce coil leakage                    4%
     Do a test calculation:
                                    Reduce/reset DSP setpoint                  4%
     • Estimate savings and costs
                                      Add/optimize optimum                     3%
     • Is the payback reasonable?
                                           start/stop
                                     Add/optimize CWST reset                   2%
                                      Source: A Study on Energy Savings and Measure Cost
                                                Effectiveness of EBCx, PECI, 2009
Page 49
Wrap-up


    Resources
     California Commissioning Collaborative
           www.cacx.org
     Better Bricks
           www.betterbricks.com
     Taylor Engineering
           www.taylor-engineering.com
     Portland Energy Conservation, Inc - PECI
           www.peci.org




Page 50
Wrap-up


    Conclusion
     Trending
           Invaluable tool
             Identify operational issues
             Calculate accurate energy savings
                                                  (and spreadsheets)
     Spreadsheet Calculations
           Straightforward
           Flexible
           Accurate
           Worth the investment in development




Page 51
Questions?




Page 52
Energy Saving Calculations for
Existing Building Commissioning




Gustav Brändström, PE
Angela Vreeland, PE

February 19, 2013

More Related Content

What's hot

Ari 550 590
Ari 550 590Ari 550 590
Ari 550 590
dhvll
 
Industrial energy efficiency techniques and energy management (1)
Industrial energy efficiency techniques and energy management (1)Industrial energy efficiency techniques and energy management (1)
Industrial energy efficiency techniques and energy management (1)
Anish Maman
 
Condensate Recovery System for Large AHU with Enthalpy Wheel
Condensate Recovery System for  Large AHU with Enthalpy WheelCondensate Recovery System for  Large AHU with Enthalpy Wheel
Condensate Recovery System for Large AHU with Enthalpy Wheel
Raji Panicker
 

What's hot (20)

Ari 550 590
Ari 550 590Ari 550 590
Ari 550 590
 
Design Calculations for Solar Water Heating System
Design Calculations for Solar Water Heating SystemDesign Calculations for Solar Water Heating System
Design Calculations for Solar Water Heating System
 
Pompa ciepła w zimnym klimacie
Pompa ciepła w zimnym klimaciePompa ciepła w zimnym klimacie
Pompa ciepła w zimnym klimacie
 
IMPLEMENTATION OF ENERGY MANAGEMENT SYSTEM TO IMPROVE ENERGY EFFICIENCY
IMPLEMENTATION OF ENERGY MANAGEMENT SYSTEM TO IMPROVE ENERGY EFFICIENCY IMPLEMENTATION OF ENERGY MANAGEMENT SYSTEM TO IMPROVE ENERGY EFFICIENCY
IMPLEMENTATION OF ENERGY MANAGEMENT SYSTEM TO IMPROVE ENERGY EFFICIENCY
 
Energy Monitoring System - WiEnergy Energy Monitoring Solution
Energy Monitoring System - WiEnergy Energy Monitoring SolutionEnergy Monitoring System - WiEnergy Energy Monitoring Solution
Energy Monitoring System - WiEnergy Energy Monitoring Solution
 
Industrial energy efficiency techniques and energy management (1)
Industrial energy efficiency techniques and energy management (1)Industrial energy efficiency techniques and energy management (1)
Industrial energy efficiency techniques and energy management (1)
 
Energy Modeling
Energy ModelingEnergy Modeling
Energy Modeling
 
Condenser pg test
Condenser pg testCondenser pg test
Condenser pg test
 
ASHRAE TC9.9 - DATA CENTER STANDARD AND BEST PRACTICES
ASHRAE TC9.9 - DATA CENTER STANDARD AND BEST PRACTICESASHRAE TC9.9 - DATA CENTER STANDARD AND BEST PRACTICES
ASHRAE TC9.9 - DATA CENTER STANDARD AND BEST PRACTICES
 
Energy Efficiency of Industrial Utilities
Energy Efficiency of Industrial UtilitiesEnergy Efficiency of Industrial Utilities
Energy Efficiency of Industrial Utilities
 
Energy efficiency in Refrigeration Systems
Energy efficiency in Refrigeration SystemsEnergy efficiency in Refrigeration Systems
Energy efficiency in Refrigeration Systems
 
Cooling load calculations
Cooling load calculationsCooling load calculations
Cooling load calculations
 
Hydronic Basics / Primary-Secondary Pumping
Hydronic Basics / Primary-Secondary PumpingHydronic Basics / Primary-Secondary Pumping
Hydronic Basics / Primary-Secondary Pumping
 
Heat pump presentation
Heat pump presentation Heat pump presentation
Heat pump presentation
 
Optimized Energy Management and planning tools for the Iron and Steel Industr...
Optimized Energy Management and planning tools for the Iron and Steel Industr...Optimized Energy Management and planning tools for the Iron and Steel Industr...
Optimized Energy Management and planning tools for the Iron and Steel Industr...
 
Energy adit microproject of chemical engineering
Energy adit microproject of chemical engineeringEnergy adit microproject of chemical engineering
Energy adit microproject of chemical engineering
 
Industrial energy efficiency - approaches, technologies and policies, Girish ...
Industrial energy efficiency - approaches, technologies and policies, Girish ...Industrial energy efficiency - approaches, technologies and policies, Girish ...
Industrial energy efficiency - approaches, technologies and policies, Girish ...
 
Condensate Recovery System for Large AHU with Enthalpy Wheel
Condensate Recovery System for  Large AHU with Enthalpy WheelCondensate Recovery System for  Large AHU with Enthalpy Wheel
Condensate Recovery System for Large AHU with Enthalpy Wheel
 
Presentation
PresentationPresentation
Presentation
 
Day 2: Energy Audit of Air Conditioning And Cooling Systems
Day 2: Energy Audit of Air Conditioning And Cooling Systems Day 2: Energy Audit of Air Conditioning And Cooling Systems
Day 2: Energy Audit of Air Conditioning And Cooling Systems
 

Viewers also liked

Chazapis elot en 15232 the impact of bacs - preso
Chazapis   elot en 15232 the impact of bacs - presoChazapis   elot en 15232 the impact of bacs - preso
Chazapis elot en 15232 the impact of bacs - preso
Nicholas Chazapis
 

Viewers also liked (19)

miScore - CEE’s Mobile App for DOE’s Home Energy Score
miScore - CEE’s Mobile App for DOE’s  Home Energy ScoremiScore - CEE’s Mobile App for DOE’s  Home Energy Score
miScore - CEE’s Mobile App for DOE’s Home Energy Score
 
Energy Saving Calculations for Recommissioning and Design
Energy Saving Calculations for Recommissioning and DesignEnergy Saving Calculations for Recommissioning and Design
Energy Saving Calculations for Recommissioning and Design
 
Nov 25, 2014 Hydro Ottawa Breakfast: Beyond the Incentive
Nov 25, 2014 Hydro Ottawa Breakfast: Beyond the IncentiveNov 25, 2014 Hydro Ottawa Breakfast: Beyond the Incentive
Nov 25, 2014 Hydro Ottawa Breakfast: Beyond the Incentive
 
Tb Cx
Tb CxTb Cx
Tb Cx
 
Commissioning_Sustainable_Buildings_JQ
Commissioning_Sustainable_Buildings_JQCommissioning_Sustainable_Buildings_JQ
Commissioning_Sustainable_Buildings_JQ
 
Progress Energy Services | verduurzamen bestaande kantoren | bijeenkomst 2|BUILD
Progress Energy Services | verduurzamen bestaande kantoren | bijeenkomst 2|BUILDProgress Energy Services | verduurzamen bestaande kantoren | bijeenkomst 2|BUILD
Progress Energy Services | verduurzamen bestaande kantoren | bijeenkomst 2|BUILD
 
Chazapis elot en 15232 the impact of bacs - preso
Chazapis   elot en 15232 the impact of bacs - presoChazapis   elot en 15232 the impact of bacs - preso
Chazapis elot en 15232 the impact of bacs - preso
 
Commissioning van NZEB - ir. Pattijn Pedro, Ingenium (1 april 2014 - Greenbri...
Commissioning van NZEB - ir. Pattijn Pedro, Ingenium (1 april 2014 - Greenbri...Commissioning van NZEB - ir. Pattijn Pedro, Ingenium (1 april 2014 - Greenbri...
Commissioning van NZEB - ir. Pattijn Pedro, Ingenium (1 april 2014 - Greenbri...
 
Introduction to energy management system
Introduction to energy management system Introduction to energy management system
Introduction to energy management system
 
Energy Audit / Energy Conservation PPT and PDF
Energy Audit / Energy Conservation PPT and PDFEnergy Audit / Energy Conservation PPT and PDF
Energy Audit / Energy Conservation PPT and PDF
 
Energy Management
Energy ManagementEnergy Management
Energy Management
 
Bms system basic
Bms system  basicBms system  basic
Bms system basic
 
Case Study of Energy Audit
Case Study of Energy Audit Case Study of Energy Audit
Case Study of Energy Audit
 
The Internet of Things (IoT) A New Generation of Tools for Energy Management ...
The Internet of Things (IoT) A New Generation of Tools for Energy Management ...The Internet of Things (IoT) A New Generation of Tools for Energy Management ...
The Internet of Things (IoT) A New Generation of Tools for Energy Management ...
 
Monitoring met energieprofielen
Monitoring met energieprofielenMonitoring met energieprofielen
Monitoring met energieprofielen
 
Monitoring Based Commissioning - A Must in The World of High Energy Efficiency
Monitoring Based Commissioning - A Must in The World of High Energy EfficiencyMonitoring Based Commissioning - A Must in The World of High Energy Efficiency
Monitoring Based Commissioning - A Must in The World of High Energy Efficiency
 
Energy management final ppt
Energy management final pptEnergy management final ppt
Energy management final ppt
 
12 Cooling Load Calculations
12 Cooling Load Calculations12 Cooling Load Calculations
12 Cooling Load Calculations
 
3 Things Every Sales Team Needs to Be Thinking About in 2017
3 Things Every Sales Team Needs to Be Thinking About in 20173 Things Every Sales Team Needs to Be Thinking About in 2017
3 Things Every Sales Team Needs to Be Thinking About in 2017
 

Similar to Energy Savings Calculations for Existing Building Commissioning

EAM ASE Breakfast Seminar NSW - April 2008
EAM ASE Breakfast Seminar NSW - April 2008EAM ASE Breakfast Seminar NSW - April 2008
EAM ASE Breakfast Seminar NSW - April 2008
jmortensen
 
Eficienta energetica in Centre de Date
Eficienta energetica in Centre de DateEficienta energetica in Centre de Date
Eficienta energetica in Centre de Date
IDG Romania
 
Compressed air manual hand book
Compressed air manual   hand bookCompressed air manual   hand book
Compressed air manual hand book
Sugestive
 

Similar to Energy Savings Calculations for Existing Building Commissioning (20)

When Does "Use Less" Become A Business
When Does "Use Less" Become A BusinessWhen Does "Use Less" Become A Business
When Does "Use Less" Become A Business
 
Performance Management In Energy Sector PowerPoint Presentation Slides
Performance Management In Energy Sector PowerPoint Presentation SlidesPerformance Management In Energy Sector PowerPoint Presentation Slides
Performance Management In Energy Sector PowerPoint Presentation Slides
 
Digital Platform for Energy Management System - Building
Digital Platform for Energy Management System - BuildingDigital Platform for Energy Management System - Building
Digital Platform for Energy Management System - Building
 
Re con
Re conRe con
Re con
 
Discussion on modern trend in measurement, Combustion control,optimization.pptx
Discussion on modern trend in measurement, Combustion control,optimization.pptxDiscussion on modern trend in measurement, Combustion control,optimization.pptx
Discussion on modern trend in measurement, Combustion control,optimization.pptx
 
Myths of Data Center Containment:Whats's True and What's Not
Myths of Data Center Containment:Whats's True and What's NotMyths of Data Center Containment:Whats's True and What's Not
Myths of Data Center Containment:Whats's True and What's Not
 
Slides: The Top 3 North America Data Center Trends for Cooling
Slides: The Top 3 North America Data Center Trends for CoolingSlides: The Top 3 North America Data Center Trends for Cooling
Slides: The Top 3 North America Data Center Trends for Cooling
 
Emerson Energy Logic
Emerson Energy LogicEmerson Energy Logic
Emerson Energy Logic
 
EAM ASE Breakfast Seminar NSW - April 2008
EAM ASE Breakfast Seminar NSW - April 2008EAM ASE Breakfast Seminar NSW - April 2008
EAM ASE Breakfast Seminar NSW - April 2008
 
Green & Beyond: Data Center Actions to Increase Business Responsiveness and R...
Green & Beyond: Data Center Actions to Increase Business Responsiveness and R...Green & Beyond: Data Center Actions to Increase Business Responsiveness and R...
Green & Beyond: Data Center Actions to Increase Business Responsiveness and R...
 
An overview of diagnostic tools used in RESNET testing
An overview of diagnostic tools used in RESNET testingAn overview of diagnostic tools used in RESNET testing
An overview of diagnostic tools used in RESNET testing
 
Industrial plant optimization in reduced dimensional spaces
Industrial plant optimization in reduced dimensional spacesIndustrial plant optimization in reduced dimensional spaces
Industrial plant optimization in reduced dimensional spaces
 
Energy Efficiency in Large Scale Systems
Energy Efficiency in Large Scale SystemsEnergy Efficiency in Large Scale Systems
Energy Efficiency in Large Scale Systems
 
Performance Measurement In Energy Sector PowerPoint Presentation Slides
Performance Measurement In Energy Sector PowerPoint Presentation SlidesPerformance Measurement In Energy Sector PowerPoint Presentation Slides
Performance Measurement In Energy Sector PowerPoint Presentation Slides
 
Eficienta energetica in Centre de Date
Eficienta energetica in Centre de DateEficienta energetica in Centre de Date
Eficienta energetica in Centre de Date
 
Compressed air manual hand book
Compressed air manual   hand bookCompressed air manual   hand book
Compressed air manual hand book
 
Utilizing Analytics to Drive Change in Buildings - Apem Sept 18 2015
Utilizing Analytics to Drive Change in Buildings - Apem Sept 18 2015Utilizing Analytics to Drive Change in Buildings - Apem Sept 18 2015
Utilizing Analytics to Drive Change in Buildings - Apem Sept 18 2015
 
Assessing Performance In Energy Sector PowerPoint Presentation Slides
Assessing Performance In Energy Sector PowerPoint Presentation SlidesAssessing Performance In Energy Sector PowerPoint Presentation Slides
Assessing Performance In Energy Sector PowerPoint Presentation Slides
 
Enhancing competitiveness and achieving sustainability
Enhancing competitiveness and achieving sustainabilityEnhancing competitiveness and achieving sustainability
Enhancing competitiveness and achieving sustainability
 
Comparative Analysis of HVAC System Based on Life Cycle Cost Analysis
Comparative Analysis of HVAC System Based on Life Cycle Cost AnalysisComparative Analysis of HVAC System Based on Life Cycle Cost Analysis
Comparative Analysis of HVAC System Based on Life Cycle Cost Analysis
 

More from Center for Energy and Environment

More from Center for Energy and Environment (20)

Field Assessment of Cold-Climate Air-Source Heat Pumps in Minnesota
Field Assessment of Cold-Climate Air-Source Heat Pumps in MinnesotaField Assessment of Cold-Climate Air-Source Heat Pumps in Minnesota
Field Assessment of Cold-Climate Air-Source Heat Pumps in Minnesota
 
Cold-Climate Air-Source Heat Pumps: Insights form the Field
Cold-Climate Air-Source Heat Pumps: Insights form the FieldCold-Climate Air-Source Heat Pumps: Insights form the Field
Cold-Climate Air-Source Heat Pumps: Insights form the Field
 
Presentation for Home Energy and Climate Finance and Policy Committee
Presentation for Home Energy and Climate Finance and Policy CommitteePresentation for Home Energy and Climate Finance and Policy Committee
Presentation for Home Energy and Climate Finance and Policy Committee
 
Achieving a Healthy Low-Carbon Economy in Minnesota
Achieving a Healthy Low-Carbon Economy in MinnesotaAchieving a Healthy Low-Carbon Economy in Minnesota
Achieving a Healthy Low-Carbon Economy in Minnesota
 
Field Assessment of Cold-Climate Air-Source Heat Pumps
Field Assessment of Cold-Climate Air-Source Heat PumpsField Assessment of Cold-Climate Air-Source Heat Pumps
Field Assessment of Cold-Climate Air-Source Heat Pumps
 
Condensing Boilers: Are they cost effective?
Condensing Boilers: Are they cost effective?Condensing Boilers: Are they cost effective?
Condensing Boilers: Are they cost effective?
 
Results from Commercial Energy Code Compliance Pilot Program
Results from Commercial Energy Code Compliance Pilot ProgramResults from Commercial Energy Code Compliance Pilot Program
Results from Commercial Energy Code Compliance Pilot Program
 
Really Selling Efficiency
Really Selling EfficiencyReally Selling Efficiency
Really Selling Efficiency
 
CEE's Strategic Electrification Forum
CEE's Strategic Electrification ForumCEE's Strategic Electrification Forum
CEE's Strategic Electrification Forum
 
Humidification Retrofits Deliver Residential Furnace Efficiency
Humidification Retrofits Deliver Residential Furnace EfficiencyHumidification Retrofits Deliver Residential Furnace Efficiency
Humidification Retrofits Deliver Residential Furnace Efficiency
 
Automated House Sealing - Aerosol Envelope Sealing of New Homes
Automated House Sealing - Aerosol Envelope Sealing of New HomesAutomated House Sealing - Aerosol Envelope Sealing of New Homes
Automated House Sealing - Aerosol Envelope Sealing of New Homes
 
Demand Control Systems Deliver Efficiency in Commercial Hot Water Use
Demand Control Systems Deliver Efficiency in Commercial Hot Water UseDemand Control Systems Deliver Efficiency in Commercial Hot Water Use
Demand Control Systems Deliver Efficiency in Commercial Hot Water Use
 
Energy Fit Homes - Realtor Benefits
Energy Fit Homes - Realtor BenefitsEnergy Fit Homes - Realtor Benefits
Energy Fit Homes - Realtor Benefits
 
Optimized Operation of Indoor Public Pool Facilities
Optimized Operation of Indoor Public Pool FacilitiesOptimized Operation of Indoor Public Pool Facilities
Optimized Operation of Indoor Public Pool Facilities
 
Deep Carbonization
Deep CarbonizationDeep Carbonization
Deep Carbonization
 
Webinar- Air Source Heat Pumps: Cold Climate Ready
Webinar- Air Source Heat Pumps: Cold Climate ReadyWebinar- Air Source Heat Pumps: Cold Climate Ready
Webinar- Air Source Heat Pumps: Cold Climate Ready
 
Small Embedded Data Center Pilot
Small Embedded Data Center PilotSmall Embedded Data Center Pilot
Small Embedded Data Center Pilot
 
The Ons & Offs of ERV Effectiveness
The Ons & Offs of ERV EffectivenessThe Ons & Offs of ERV Effectiveness
The Ons & Offs of ERV Effectiveness
 
New Technology for Efficient Multifamily Building Envelope Sealing
New Technology for Efficient Multifamily Building Envelope SealingNew Technology for Efficient Multifamily Building Envelope Sealing
New Technology for Efficient Multifamily Building Envelope Sealing
 
Cost-Effective Duct Retrofit & Leakage Reduction
Cost-Effective Duct Retrofit & Leakage ReductionCost-Effective Duct Retrofit & Leakage Reduction
Cost-Effective Duct Retrofit & Leakage Reduction
 

Recently uploaded

Structuring Teams and Portfolios for Success
Structuring Teams and Portfolios for SuccessStructuring Teams and Portfolios for Success
Structuring Teams and Portfolios for Success
UXDXConf
 

Recently uploaded (20)

The Value of Certifying Products for FDO _ Paul at FIDO Alliance.pdf
The Value of Certifying Products for FDO _ Paul at FIDO Alliance.pdfThe Value of Certifying Products for FDO _ Paul at FIDO Alliance.pdf
The Value of Certifying Products for FDO _ Paul at FIDO Alliance.pdf
 
ECS 2024 Teams Premium - Pretty Secure
ECS 2024   Teams Premium - Pretty SecureECS 2024   Teams Premium - Pretty Secure
ECS 2024 Teams Premium - Pretty Secure
 
ASRock Industrial FDO Solutions in Action for Industrial Edge AI _ Kenny at A...
ASRock Industrial FDO Solutions in Action for Industrial Edge AI _ Kenny at A...ASRock Industrial FDO Solutions in Action for Industrial Edge AI _ Kenny at A...
ASRock Industrial FDO Solutions in Action for Industrial Edge AI _ Kenny at A...
 
How Red Hat Uses FDO in Device Lifecycle _ Costin and Vitaliy at Red Hat.pdf
How Red Hat Uses FDO in Device Lifecycle _ Costin and Vitaliy at Red Hat.pdfHow Red Hat Uses FDO in Device Lifecycle _ Costin and Vitaliy at Red Hat.pdf
How Red Hat Uses FDO in Device Lifecycle _ Costin and Vitaliy at Red Hat.pdf
 
What's New in Teams Calling, Meetings and Devices April 2024
What's New in Teams Calling, Meetings and Devices April 2024What's New in Teams Calling, Meetings and Devices April 2024
What's New in Teams Calling, Meetings and Devices April 2024
 
FDO for Camera, Sensor and Networking Device – Commercial Solutions from VinC...
FDO for Camera, Sensor and Networking Device – Commercial Solutions from VinC...FDO for Camera, Sensor and Networking Device – Commercial Solutions from VinC...
FDO for Camera, Sensor and Networking Device – Commercial Solutions from VinC...
 
Structuring Teams and Portfolios for Success
Structuring Teams and Portfolios for SuccessStructuring Teams and Portfolios for Success
Structuring Teams and Portfolios for Success
 
BT & Neo4j _ How Knowledge Graphs help BT deliver Digital Transformation.pptx
BT & Neo4j _ How Knowledge Graphs help BT deliver Digital Transformation.pptxBT & Neo4j _ How Knowledge Graphs help BT deliver Digital Transformation.pptx
BT & Neo4j _ How Knowledge Graphs help BT deliver Digital Transformation.pptx
 
Syngulon - Selection technology May 2024.pdf
Syngulon - Selection technology May 2024.pdfSyngulon - Selection technology May 2024.pdf
Syngulon - Selection technology May 2024.pdf
 
Designing for Hardware Accessibility at Comcast
Designing for Hardware Accessibility at ComcastDesigning for Hardware Accessibility at Comcast
Designing for Hardware Accessibility at Comcast
 
WebAssembly is Key to Better LLM Performance
WebAssembly is Key to Better LLM PerformanceWebAssembly is Key to Better LLM Performance
WebAssembly is Key to Better LLM Performance
 
AI mind or machine power point presentation
AI mind or machine power point presentationAI mind or machine power point presentation
AI mind or machine power point presentation
 
IESVE for Early Stage Design and Planning
IESVE for Early Stage Design and PlanningIESVE for Early Stage Design and Planning
IESVE for Early Stage Design and Planning
 
Extensible Python: Robustness through Addition - PyCon 2024
Extensible Python: Robustness through Addition - PyCon 2024Extensible Python: Robustness through Addition - PyCon 2024
Extensible Python: Robustness through Addition - PyCon 2024
 
Powerful Start- the Key to Project Success, Barbara Laskowska
Powerful Start- the Key to Project Success, Barbara LaskowskaPowerful Start- the Key to Project Success, Barbara Laskowska
Powerful Start- the Key to Project Success, Barbara Laskowska
 
State of the Smart Building Startup Landscape 2024!
State of the Smart Building Startup Landscape 2024!State of the Smart Building Startup Landscape 2024!
State of the Smart Building Startup Landscape 2024!
 
Using IESVE for Room Loads Analysis - UK & Ireland
Using IESVE for Room Loads Analysis - UK & IrelandUsing IESVE for Room Loads Analysis - UK & Ireland
Using IESVE for Room Loads Analysis - UK & Ireland
 
TopCryptoSupers 12thReport OrionX May2024
TopCryptoSupers 12thReport OrionX May2024TopCryptoSupers 12thReport OrionX May2024
TopCryptoSupers 12thReport OrionX May2024
 
Portal Kombat : extension du réseau de propagande russe
Portal Kombat : extension du réseau de propagande russePortal Kombat : extension du réseau de propagande russe
Portal Kombat : extension du réseau de propagande russe
 
Working together SRE & Platform Engineering
Working together SRE & Platform EngineeringWorking together SRE & Platform Engineering
Working together SRE & Platform Engineering
 

Energy Savings Calculations for Existing Building Commissioning

  • 1. Welcome to the Webinar on Energy Saving Calculations for Existing Building Commissioning We’ll start the presentation shortly. Hover your cursor at the top of your screen to access the WebEx menu bar and open your Chat window. We will end with an open discussion, but feel free to ask clarifying or technical support questions during the presentation through your Chat window. Gustav Brändström, PE Angela Vreeland, PE February 19, 2013
  • 2. Energy Saving Calculations for Existing Building Commissioning Gustav Brändström, PE Angela Vreeland, PE February 19, 2013
  • 3. Agenda Agenda  Introduction  Why use spreadsheet calculations?  Trending and Trend Data  TMY and Bin Data  Top Energy Saving Measures in EBCx  AHU Measure  Optimize Airside Economizer  Pump Measure  Install VFD on Hot Water Pump  Wrap-up  Questions Page 3
  • 4. Introduction Why Use Spreadsheet Calculations?  Customizable for any application  Can be based on actual building operation  Applicable to multiple scenarios with little modification  TRAP: Do not double count savings! Remember to include interactions between findings and equipment.  Scheduling > Controls changes > Retrofits  Central system > Major equipment > Terminal equipment Page 4
  • 5. Introduction Why Use Spreadsheet Calculations?  Most 3rd party tools apply to specific scenarios  “Square peg in round hole”  All inputs must be re-entered for each case  Energy modeling is not economical for analysis of individual equipment  Time-consuming  Not intent of modeling software Page 5
  • 6. Introduction Trending and Trend Data  Trending – brief overview  The process of capturing time series data on equipment operation  Data is exported from a Building Automation System (BAS) or data loggers for spreadsheet analysis  Data set-up, collection, processing, and analysis are time consuming  Allows us to understand how the equipment operates See the Innovation Exchange’s Webinar on Trending titled: Using Building Automation Systems as a Cx Tool Page 6
  • 7. Introduction Trending and Trend Data  Why use trend data?  Trend data allows you to identify operational issues you wouldn’t find otherwise.  Functional performance tests and other tools can’t capture all modes of operation  Trend data allows you to more accurately calculate savings Page 7
  • 8. Introduction TMY and Bin Data  Energy savings calculations are based on OAT  Typical Meteorological Year Weather Data  Normalized weather  Covers at least 15 year timeframe  Average and typical, not average  “Major” cities only  Get from NREL  http://www.nrel.gov/rredc/solar_data.html  Bin Data  Grouped or “binned” data  Increments vary depending on system characteristics  Outdoor temperature is typically put in 5 F bins  Used in most spreadsheet calculations Page 8
  • 9. Introduction TMY and Bin Data  TRICK: AVERAGEIFS() and COUNTIFS() in Excel  These functions make creating bins out of data super easy!!  AVERAGEIFS() - Average value of a range, given criteria  COUNTIFS() - Number of occurrences in a range, given criteria OAT Bins Avg OAT (F) Hours Hours ON 60 65 63.7 3 1.5 65 70 68.5 2.25 0.75 70 75 72.4 3.25 1.25 75 80 77.8 2 1.25 80 85 82.5 8.25 5.75 85 90 85.8 1.25 1.25 =AVERAGEIFS(Avg Range, CriteriaRange1, Criteria1, CriteriaRange2,Criteria2, …) =AVERAGEIFS(OAT Column, OAT Column,">="&BinLL, OAT Column,"<"&BinUL) Page 9
  • 10. Agenda Agenda  Introduction  Why use spreadsheet calculations?  Trending and Trend Data  TMY and Bin Data  Top Energy Saving Measures in EBCx  AHU Measure  Optimize Airside Economizer  Pump Measure  Install VFD on Hot Water Pump  Wrap-up  Questions Page 10
  • 11. AHU Measure Top Energy Saving Measures in EBCx Key Measure Mix % of Total Savings Revise control sequence 21% Reduce equipment runtime 15% Optimize airside economizer 12% Add/optimize SAT reset 8% Add VFD to pump 6% Reduce coil leakage 4% Reduce/reset DSP setpoint 4% Add/optimize optimum start/stop 3% Add/optimize CWST reset 2% Source: A Study on Energy Savings and Measure Cost Effectiveness of Page 11 EBCx, PECI, 2009
  • 12. AHU Measure Optimize Airside Economizer  Four most common high limit control strategies  Fixed Drybulb Temperature- OAT  Differential Drybulb Temperature- OAT vs RAT  Fixed Enthalpy- OAh Enthalpy is calculated from drybulb temperature and humidity  Differential Enthalpy- OAh vs RAh Page 12 ???
  • 13. AHU Measure Optimize Airside Economizer  Economizers malfunction frequently  Stuck outside damper  Outside air (OA) flow measuring station error  Temperature or humidity sensor out of calibration Page 13
  • 14. AHU Measure Optimize Airside Economizer  Economizer control errors are common  Incorrect high and/or low limit setpoint  Incorrect minimum outside air setpoint  Lockout between economizer and mechanical cooling  Result in  A loss of “free cooling” opportunity  Increased cooling load  Increased heating load Page 14
  • 15. AHU Measure Optimize Airside Economizer  How do we know if something is wrong?  Calculate the %OA where: OAT = Outside Air Temperature RAT = Return Air Temperature MAT = Mixed Air Temperature  Plot %OA against OAT and look at the pattern Page 15
  • 16. - IDEAL PATTERN Economizer Lockout ~ 70°F Page 16
  • 17. AHU Measure Optimize Airside Economizer  Why should the high limit setpoint be ~70 F?  High limit of 71 F in MN was found to be ideal  Taylor Engineering Research  Best economizer control strategy is provided for each region  November 2010 ASHRAE Journal (Vol. 52, No. 11)  TRAP: Humidity Sensors are Error-Prone  Avoid enthalpy high limit control  Iowa Energy Center Research  http://www.iowaenergycenter.org/wp- content/uploads/2012/05/PTR_Humidity_Rev.pdf Page 17
  • 18. AHU Measure Optimize Airside Economizer Example  Finding (problem)  Economizer high limit lockout is 80 F  Measure (solution)  Change the lockout to 70 F Page 18
  • 19. - HIGH LIMIT TOO HIGH Lower the High Limit Setpoint: 80°F to 70°F Page 19
  • 20. AHU Measure Optimize Airside Economizer Example  Spreadsheet Calculation Layout  Reducing the high limit setpoint will lead to savings whenever the outside air damper is open more than it should be 1 2 3 A B C D E F G H I J K L Current Proposed OAT Dry OAT OA OA OA OA AHU On RAT Savings Bulb Bin Dry Bulb OA OA Flow Cooling Cooling OA OA Flow Cooling Cooling Energy Input Energy Input F F Hours F % CFM kBtus kWh % CFM kBtus kWh kWh 60/64 62.6 321 70.8 67.9% 9,840 0 0 67.9% 9,840 0 0 0 65/69 68.1 294 71.2 87.7% 12,712 0 0 87.7% 12,712 0 0 0 70/74 72.5 265 71.6 95.5% 13,847 3,400 340 10.0% 1,450 356 36 304 75/79 76.9 317 71.6 78.0% 11,307 20,534 2,053 10.0% 1,450 2,633 263 1790 80/84 82.1 284 72.6 18.2% 2,643 7,688 769 10.0% 1,450 4,218 422 347 85/89 87.8 152 72.0 10.0% 1,450 3,758 376 10.0% 1,450 3,758 376 0 90/94 91.9 54 73.0 10.0% 1,450 1,594 159 10.0% 1,450 1,594 159 0 2,442 Page 20
  • 21. AHU Measure Optimize Airside Economizer Example 1 A B C D EColumn A- OAT Bins F G H I J K L Current Proposed OAT Dry OAT  5 F Bins OA OA OA OA AHU On RAT Bulb Bin Dry Bulb OA OA Flow Cooling Cooling OA OA Flow Cooling Cooling Energy Input Energy Input F F Hours F %Column B- Average OAT for Bin CFM kBtus% kWh CFM kBtus kWh 60/64 62.6 321 70.8  Obtain from 0TMY Data 67.9% 9,840 0 67.9% 9,840 0 0 65/69 68.1 294 71.2 87.7% 12,712 0 0 87.7% 12,712 0 0 70/74 72.5 265 71.6  Use AVERAGEIFS340 95.5% 13,847 3,400 10.0% 1,450 356 36 75/79 76.9 317 71.6 78.0% 11,307 20,534 2,053 10.0% 1,450 2,633 263 80/84 82.1 284 72.6 18.2% 2,643 7,688 769 10.0% 1,450 4,218 422 85/89 87.8 152 72.0 Column C- Total Hours the AHU operates 10.0% 1,450 3,758 376 10.0% 1,450 3,758 376 90/94 91.9 54 73.0 10.0% during Bin 1,450 1,594 159 10.0% 1,450 1,594 159  Obtain from trends of SF Status or VFD Speed and OAT  Use COUNTIFS Page 21
  • 22. AHU Measure Optimize Airside Economizer Example 1 A B C D EColumn D- Average RAT during JBin F G H I K L Current Proposed OAT Dry OAT  Obtain from trendsOA RAT and OAT OA of OA OA AHU On RAT Bulb Bin Dry Bulb  OA RAT vs OAT to see OA pattern OA Plot Flow Cooling Cooling overall OA Flow Cooling Cooling Energy Input Energy Input F F Hours F  % Use AVERAGEIFS- Filter for when AHU is ON CFM kBtus kWh % CFM kBtus kWh 60/64 62.6 321 70.8 67.9% 9,840 0 0 67.9% 9,840 0 0 65/69 68.1 294 71.2 87.7% 12,712 0 0 87.7% 12,712 0 0 70/74 72.5 265 71.6 95.5% 13,847 3,400 340 10.0% 1,450 356 36 75/79 76.9 317 71.6 78.0% 11,307 20,534 2,053 10.0% 1,450 2,633 263 80/84 82.1 284 72.6 18.2% 2,643 7,688 769 10.0% 1,450 4,218 422 85/89 87.8 152 72.0 10.0% 1,450 3,758 376 10.0% 1,450 3,758 376 90/94 91.9 54 73.0 10.0% 1,450 1,594 159 10.0% 1,450 1,594 159 Page 22
  • 23. AHU Measure Optimize Airside Economizer Example  Spreadsheet Calculation Layout 1 2 3 A B C D E F G H I J K L Current Proposed OAT Dry OAT OA OA OA OA AHU On RAT Savings Bulb Bin Dry Bulb OA OA Flow Cooling Cooling OA OA Flow Cooling Cooling Energy Input Energy Input F F Hours F % CFM kBtus kWh % CFM kBtus kWh kWh 60/64 62.6 321 70.8 67.9% 9,840 0 0 67.9% 9,840 0 0 0 65/69 68.1 294 71.2 87.7% 12,712 0 0 87.7% 12,712 0 0 0 70/74 72.5 265 71.6 95.5% 13,847 3,400 340 10.0% 1,450 356 36 304 75/79 76.9 317 71.6 78.0% 11,307 20,534 2,053 10.0% 1,450 2,633 263 1790 80/84 82.1 284 72.6 18.2% 2,643 7,688 769 10.0% 1,450 4,218 422 347 85/89 87.8 152 72.0 10.0% 1,450 3,758 376 10.0% 1,450 3,758 376 0 90/94 91.9 54 73.0 10.0% 1,450 1,594 159 10.0% 1,450 1,594 159 0 2,442 Page 23
  • 24. AHU Measure Optimize Airside Economizer Example 2 A E F G H Column E- Average %OA during Bin Current OAT Dry  Obtain from trends of MAT, RAT, and OA OA Bulb Bin OA OA Flow Cooling Cooling OAT Energy Input  Plot %OA vs OAT to see overall pattern F % CFM kBtus kWh  Use AVERAGEIFS- Filter for when AHU 60/64 67.9% 9,840 0 0 65/69 87.7% 12,712 0 0 is ON 70/74 95.5% 13,847 3,400 340 75/79 78.0% 11,307 20,534 2,053 80/84 18.2% 2,643 7,688 769 85/89 10.0% 1,450 3,758 376 90/94 10.0% 1,450 1,594 159 Page 24
  • 25. AHU Measure Optimize Airside Economizer Example 2 A E F G H Column F- OA Flow Current OAT Dry  Calculated using equation below OA OA Bulb Bin OA OA Flow Cooling Cooling  SF Speed must be accounted for with Energy Input variable volume AHUs F % CFM kBtus kWh 60/64 67.9% 9,840 0 0 65/69 87.7% 12,712 0 0 70/74 95.5% 13,847 3,400 340 Column G- Cooling Energy 75/79 78.0% 11,307 20,534 2,053 80/84 18.2% 2,643 7,688 769  Energy required to cool OA 85/89 10.0% 1,450 3,758 376  Calculated using equation below 90/94 10.0% 1,450 1,594 159 Page 25
  • 26. AHU Measure Optimize Airside Economizer Example 2 A E F G H Column H- Cooling Input Current OAT Dry  Calculated using equation below OA OA Bulb Bin OA OA Flow Cooling Cooling Energy Input F % CFM kBtus kWh 60/64 67.9% 9,840 0 0 65/69 87.7% 12,712 0 0 70/74 95.5% 13,847 3,400 340 75/79 78.0% 11,307 20,534 2,053 80/84 18.2% 2,643 7,688 769 85/89 10.0% 1,450 3,758 376 90/94 10.0% 1,450 1,594 159 Page 26
  • 27. AHU Measure Optimize Airside Economizer Example  Spreadsheet Calculation Layout 1 2 3 A B C D E F G H I J K L Current Proposed OAT Dry OAT OA OA OA OA AHU On RAT Savings Bulb Bin Dry Bulb OA OA Flow Cooling Cooling OA OA Flow Cooling Cooling Energy Input Energy Input F F Hours F % CFM kBtus kWh % CFM kBtus kWh kWh 60/64 62.6 321 70.8 67.9% 9,840 0 0 67.9% 9,840 0 0 0 65/69 68.1 294 71.2 87.7% 12,712 0 0 87.7% 12,712 0 0 0 70/74 72.5 265 71.6 95.5% 13,847 3,400 340 10.0% 1,450 356 36 304 75/79 76.9 317 71.6 78.0% 11,307 20,534 2,053 10.0% 1,450 2,633 263 1790 80/84 82.1 284 72.6 18.2% 2,643 7,688 769 10.0% 1,450 4,218 422 347 85/89 87.8 152 72.0 10.0% 1,450 3,758 376 10.0% 1,450 3,758 376 0 90/94 91.9 54 73.0 10.0% 1,450 1,594 159 10.0% 1,450 1,594 159 0 2,442 Page 27
  • 28. AHU Measure Optimize Airside Economizer Example 3 A I J K L Columns I thru L Proposed OAT Dry  Repeat the same analysis for OA OA Bulb Bin OA OA Flow Cooling Cooling Proposed Scenario Energy Input  Above 70 F, the %OA will drop to F % CFM kBtus kWh minimum position 60/64 67.9% 9,840 0 0 65/69 87.7% 12,712 0 0  Based on data at low OATs, the 70/74 10.0% 1,450 356 36 minimum %OA is 10% 75/79 10.0% 1,450 2,633 263 80/84 10.0% 1,450 4,218 422 85/89 10.0% 1,450 3,758 376 90/94 10.0% 1,450 1,594 159 Page 28
  • 29. AHU Measure Optimize Airside Economizer Example A B C D E F G H I J K L Current Proposed OAT Dry OAT OA OA OA OA AHU On RAT Savings Bulb Bin Dry Bulb OA OA Flow Cooling Cooling OA OA Flow Cooling Cooling Energy Input Energy Input F F Hours F % CFM kBtus kWh % CFM kBtus kWh kWh 60/64 62.6 321 70.8 67.9% 9,840 0 0 67.9% 9,840 0 0 0 65/69 68.1 294 71.2 87.7% 12,712 0 0 87.7% 12,712 0 0 0 70/74 72.5 265 71.6 95.5% 13,847 3,400 340 10.0% 1,450 356 36 304 75/79 76.9 317 71.6 78.0% 11,307 20,534 2,053 10.0% 1,450 2,633 263 1790 80/84 82.1 284 72.6 18.2% 2,643 7,688 769 10.0% 1,450 4,218 422 347 85/89 87.8 152 72.0 10.0% 1,450 3,758 376 10.0% 1,450 3,758 376 0 90/94 91.9 54 73.0 10.0% 1,450 1,594 159 10.0% 1,450 1,594 159 0 2,442  Savings  2,442 kWh annually or $170 at 7¢/kWh  ~10% of energy used to cool OA  No cost to implement Page 29
  • 30. AHU Measure Optimize Airside Economizer  Summary  Economizers malfunction often, but fixing them is typically very easy and cost-effective  Additional considerations….  Sometimes fixing the issue leads to more energy use  An AHU may economize at OATs as low as 20 or 30 F  The fewer sensors the economizer relies on, the better Page 30
  • 31. Agenda Agenda  Introduction  Why use spreadsheet calculations?  Trending and Trend Data  TMY and Bin Data  Top Energy Saving Measures in EBCx  AHU Measure  Optimize Airside Economizer  Pump Measure  Install VFD on Hot Water Pump  Wrap-up  Questions Page 31
  • 32. Pump Measure Top Energy Saving Measures in EBCx Key Measure Mix % of Total Savings Revise control sequence 21% Reduce equipment runtime 15% Optimize airside economizer 12% Add/optimize SAT reset 8% Add VFD to pump 6% Reduce coil leakage 4% Reduce/reset DSP setpoint 4% Add/optimize optimum start/stop 3% Add/optimize CWST reset 2% Source: A Study on Energy Savings and Measure Cost Effectiveness of Page 32 EBCx, PECI, 2009
  • 33. Pump Measure Install VFD on Hot Water Pump  Constant volume pumping is common in existing buildings.  Hot water loops come in many variants; primary, primary/secondary, primary/tertiary, etc.  Energy savings from reducing the pump speed  Opportunities exist when the  drop in temperature is low Page 33
  • 34. TRICK: Plot HW dT vs OAT. Example of low temperature drop Design Loop dT = 48°F Page 34
  • 35. Pump Measure Install VFD on Hot Water Pump  Constant volume pumping is common in existing buildings.  Hot water loops come in many variants; primary, primary/secondary, primary/tertiary, etc.  Energy savings from reducing the pump speed  Opportunities exist when the  drop in temperature is low, and/or  use in the AHUs are low. Page 35
  • 36. TRICK: Plot # of AHUs heating vs OAT. Example of Low use of heating at the AHUs Page 36
  • 37. Pump Measure Install VFD on Hot Water Pump  Example  Finding (problem)  Secondary Hot Water Loop Pump runs excessively  Measure (solution)  Install VFD on 40hp Pump, close off three way valves, and install differential pressure sensor Page 37
  • 38. Pump Measure Install VFD on Hot Water Pump  Calculation Layout 1 2 3 % of Total Flow %Req. Energy Use Bin 11.8% 11.3% 7.0% 13.1% 5.5% 15.6% 14.8% 20.9% Flow Current Proposed OAT Bin Hours AHU-1 AHU-2 AHU-3 AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%) (kWh) (kWh) -20 -10 248 100% 59% 100% 63% 58% 64% 89% 77% 76% 6,994 4,061 -10 0 309 100% 62% 100% 63% 60% 55% 73% 66% 70% 8,714 4,328 0 10 436 100% 68% 100% 54% 62% 52% 68% 48% 65% 12,295 5,226 10 20 696 100% 48% 100% 44% 45% 40% 48% 36% 53% 19,627 5,600 20 30 1074 100% 27% 100% 28% 27% 31% 27% 15% 39% 30,287 4,622 30 40 1224 100% 18% 100% 0% 10% 20% 3% 8% 30% 34,517 3,107 40 50 1114 100% 8% 100% 0% 3% 14% 0% 7% 30% 31,415 2,827 50 60 1135 100% 0% 100% 0% 0% 9% 0% 3% 30% 32,007 2,881 60 70 1157 0% 0% 0% 0% 0% 0% 0% 0% 30% 32,627 2,936 208,483 35,588 Savings 172,895 Page 38
  • 39. Pump Measure Install VFD on Hot Water Pump  Calculation of OAT bins 1 % of Total Flow %Req. Energy Use Bin 11.8% 11.3% 7.0% 13.1% 5.5% 15.6% 14.8% 20.9% Flow Current Proposed OAT Bin Hours AHU-1 AHU-2 AHU-3 AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%) (kWh) (kWh) -20 -10 248 100% 59% 100% 63% 58% 64% 89% 77% 76% 6,994 4,061 -10 0 309 100% 62% 100% 63% 60% 55% 73% 66% 70% 8,714 4,328 0 10 436 100% 68% 100% 54% 62% 52% 68% 48% 65% 12,295 5,226 10 20 696 100% 48% 100% 44% 45% 40% 48% 36% 53% 19,627 5,600 20 30 1074 100% 27% 100% 28% 27% 31% 27% 15% 39% 30,287 4,622 30 40 1224 100% 18% 100% 0% 10% 20% 3% 8% 30% 34,517 3,107 40 50 1114 100% 8% 100% 0% 3% 14% 0% 7% 30% 31,415 2,827 50 60 1135 100% 0% 100% 0% 0% 9% 0% 3% 30% 32,007 2,881 60 70 1157 0% 0% 0% 0% 0% 0% 0% 0% 30% 32,627 2,936 208,483 35,588 Savings 172,895 Page 39
  • 40. Pump Measure Install VFD on Hot Water Pump  Calculation of AHU heating use  % of total loop flow through each AHU 2 % of Total Flow %Req. Energy Use Bin 11.8% 11.3% 7.0% 13.1% 5.5% 15.6% 14.8% 20.9% Flow Current Proposed OAT Bin Hours AHU-1 AHU-2 AHU-3 AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%) (kWh) (kWh) -20 -10 248 100% 59% 100% 63% 58% 64% 89% 77% 76% 6,994 4,061 -10 0 309 100% 62% 100% 63% 60% 55% 73% 66% 70% 8,714 4,328 0 10 436 100% 68% 100% 54% 62% 52% 68% 48% 65% 12,295 5,226 10 20 696 100% 48% 100% 44% 45% 40% 48% 36% 53% 19,627 5,600 20 30 1074 100% 27% 100% 28% 27% 31% 27% 15% 39% 30,287 4,622 30 40 1224 100% 18% 100% 0% 10% 20% 3% 8% 30% 34,517 3,107 40 50 1114 100% 8% 100% 0% 3% 14% 0% 7% 30% 31,415 2,827 50 60 1135 100% 0% 100% 0% 0% 9% 0% 3% 30% 32,007 2,881 60 70 1157 0% 0% 0% 0% 0% 0% 0% 0% 30% 32,627 2,936 208,483 35,588 Savings 172,895 Page 40
  • 41. Pump Measure Install VFD on Hot Water Pump  Calculation of AHU heating use  TRAP: Do not assume linear load  TRICK: AVERAGEIFS() 2 % of Total Flow %Req. Energy Use Bin 11.8% 11.3% 7.0% 13.1% 5.5% 15.6% 14.8% 20.9% Flow Current Proposed OAT Bin Hours AHU-1 AHU-2 AHU-3 AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%) (kWh) (kWh) -20 -10 248 100% 59% 100% 63% 58% 64% 89% 77% 76% 6,994 4,061 -10 0 309 100% 62% 100% 63% 60% 55% 73% 66% 70% 8,714 4,328 0 10 436 100% 68% 100% 54% 62% 52% 68% 48% 65% 12,295 5,226 10 20 696 100% 48% 100% 44% 45% 40% 48% 36% 53% 19,627 5,600 20 30 1074 100% 27% 100% 28% 27% 31% 27% 15% 39% 30,287 4,622 30 40 1224 100% 18% 100% 0% 10% 20% 3% 8% 30% 34,517 3,107 40 50 1114 100% 8% 100% 0% 3% 14% 0% 7% 30% 31,415 2,827 50 60 1135 100% 0% 100% 0% 0% 9% 0% 3% 30% 32,007 2,881 60 70 1157 0% 0% 0% 0% 0% 0% 0% 0% 30% 32,627 2,936 208,483 35,588 Savings 172,895 Page 41
  • 42. Pump Measure Install VFD on Hot Water Pump  Calculation of AHU heating use – Three-way valves 2 % of Total Flow %Req. Energy Use Bin 11.8% 11.3% 7.0% 13.1% 5.5% 15.6% 14.8% 20.9% Flow Current Proposed OAT Bin Hours AHU-1 AHU-2 AHU-3 AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%) (kWh) (kWh) -20 -10 248 100% 59% 100% 63% 58% 64% 89% 77% 76% 6,994 4,061 -10 0 309 100% 62% 100% 63% 60% 55% 73% 66% 70% 8,714 4,328 0 10 436 100% 68% 100% 54% 62% 52% 68% 48% 65% 12,295 5,226 10 20 696 100% 48% 100% 44% 45% 40% 48% 36% 53% 19,627 5,600 20 30 1074 100% 27% 100% 28% 27% 31% 27% 15% 39% 30,287 4,622 30 40 1224 100% 18% 100% 0% 10% 20% 3% 8% 30% 34,517 3,107 40 50 1114 100% 8% 100% 0% 3% 14% 0% 7% 30% 31,415 2,827 50 60 1135 100% 0% 100% 0% 0% 9% 0% 3% 30% 32,007 2,881 60 70 1157 0% 0% 0% 0% 0% 0% 0% 0% 30% 32,627 2,936 208,483 35,588 Savings 172,895 Page 42
  • 43. Pump Measure Install VFD on Hot Water Pump  Calculation of total heating use  TRAP: Do not assume 30% minimum flow (as I did) 2 % of Total Flow %Req. Energy Use Bin 11.8% 11.3% 7.0% 13.1% 5.5% 15.6% 14.8% 20.9% Flow Current Proposed OAT Bin Hours AHU-1 AHU-2 AHU-3 AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%) (kWh) (kWh) -20 -10 248 100% 59% 100% 63% 58% 64% 89% 77% 76% 6,994 4,061 -10 0 309 100% 62% 100% 63% 60% 55% 73% 66% 70% 8,714 4,328 0 10 436 100% 68% 100% 54% 62% 52% 68% 48% 65% 12,295 5,226 10 20 696 100% 48% 100% 44% 45% 40% 48% 36% 53% 19,627 5,600 20 30 1074 100% 27% 100% 28% 27% 31% 27% 15% 39% 30,287 4,622 30 40 1224 100% 18% 100% 0% 10% 20% 3% 8% 30% 34,517 3,107 40 50 1114 100% 8% 100% 0% 3% 14% 0% 7% 30% 31,415 2,827 50 60 1135 100% 0% 100% 0% 0% 9% 0% 3% 30% 32,007 2,881 60 70 1157 0% 0% 0% 0% 0% 0% 0% 0% 30% 32,627 2,936 208,483 35,588 Savings 172,895 Page 43
  • 44. Pump Measure Install VFD on Hot Water Pump  Calculation of total heating use 3 % of Total Flow %Req. Energy Use Bin 11.8% 11.3% 7.0% 13.1% 5.5% 15.6% 14.8% 20.9% Flow Current Proposed OAT Bin Hours AHU-1 AHU-2 AHU-3 AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%) (kWh) (kWh) -20 -10 248 100% 59% 100% 63% 58% 64% 89% 77% 76% 6,994 4,061 -10 0 309 100% 62% 100% 63% 60% 55% 73% 66% 70% 8,714 4,328 0 10 436 100% 68% 100% 54% 62% 52% 68% 48% 65% 12,295 5,226 10 20 696 100% 48% 100% 44% 45% 40% 48% 36% 53% 19,627 5,600 20 30 1074 100% 27% 100% 28% 27% 31% 27% 15% 39% 30,287 4,622 30 40 1224 100% 18% 100% 0% 10% 20% 3% 8% 30% 34,517 3,107 40 50 1114 100% 8% 100% 0% 3% 14% 0% 7% 30% 31,415 2,827 50 60 1135 100% 0% 100% 0% 0% 9% 0% 3% 30% 32,007 2,881 60 70 1157 0% 0% 0% 0% 0% 0% 0% 0% 30% 32,627 2,936 208,483 35,588 Savings 172,895 Page 44
  • 45. Pump Measure Install VFD on Hot Water Pump  Calculation of current (100% flow) vs proposed pump energy use 3 % of Total Flow %Req. Energy Use Bin 11.8% 11.3% 7.0% 13.1% 5.5% 15.6% 14.8% 20.9% Flow Current Proposed OAT Bin Hours AHU-1 AHU-2 AHU-3 AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%) (kWh) (kWh) -20 -10 248 100% 59% 100% 63% 58% 64% 89% 77% 76% 6,994 4,061 -10 0 309 100% 62% 100% 63% 60% 55% 73% 66% 70% 8,714 4,328 0 10 436 100% 68% 100% 54% 62% 52% 68% 48% 65% 12,295 5,226 10 20 696 100% 48% 100% 44% 45% 40% 48% 36% 53% 19,627 5,600 20 30 1074 100% 27% 100% 28% 27% 31% 27% 15% 39% 30,287 4,622 30 40 1224 100% 18% 100% 0% 10% 20% 3% 8% 30% 34,517 3,107 40 50 1114 100% 8% 100% 0% 3% 14% 0% 7% 30% 31,415 2,827 50 60 1135 100% 0% 100% 0% 0% 9% 0% 3% 30% 32,007 2,881 60 70 1157 0% 0% 0% 0% 0% 0% 0% 0% 30% 32,627 2,936 208,483 35,588 Savings 172,895 Page 45
  • 46. Pump Measure Install VFD on Hot Water Pump  Saves 172,895 kWh annually, or $12,100 at 7¢/kWh. 83% of the current pump energy use saved! 3 % of Total Flow %Req. Energy Use Bin 11.8% 11.3% 7.0% 13.1% 5.5% 15.6% 14.8% 20.9% Flow Current Proposed OAT Bin Hours AHU-1 AHU-2 AHU-3 AHU-4 AHU-5 AHU-6 AHU-7 AHU-8 (min 30%) (kWh) (kWh) -20 -10 248 100% 59% 100% 63% 58% 64% 89% 77% 76% 6,994 4,061 -10 0 309 100% 62% 100% 63% 60% 55% 73% 66% 70% 8,714 4,328 0 10 436 100% 68% 100% 54% 62% 52% 68% 48% 65% 12,295 5,226 10 20 696 100% 48% 100% 44% 45% 40% 48% 36% 53% 19,627 5,600 20 30 1074 100% 27% 100% 28% 27% 31% 27% 15% 39% 30,287 4,622 30 40 1224 100% 18% 100% 0% 10% 20% 3% 8% 30% 34,517 3,107 40 50 1114 100% 8% 100% 0% 3% 14% 0% 7% 30% 31,415 2,827 50 60 1135 100% 0% 100% 0% 0% 9% 0% 3% 30% 32,007 2,881 60 70 1157 0% 0% 0% 0% 0% 0% 0% 0% 30% 32,627 2,936 208,483 35,588 Savings 172,895 Page 46
  • 47. Pump Measure Install VFD on Hot Water Pump  Summary of Measure  Keep the pump running at as low of a speed as possible  TRICK: In conjunction with adding a VFD, look at the scheduling.  TRAP: If there are different modes of operation, account for them! (Morning Warm-up, freeze protection, etc.)  SAVE LOTS OF ENERGY!  Implementation cost $29,000 (incl. commissioning)  Energy Savings $12,100  Simple Payback 2.4 years Page 47
  • 48. Agenda Agenda  Introduction  Why use spreadsheet calculations?  Trending and Trend Data  TMY and Bin Data  Top Energy Saving Measures in EBCx  AHU Measure  Optimize Airside Economizer  Pump Measure  Install VFD on Hot Water Pump  Wrap-up  Questions Page 48
  • 49. Introduction Target High Energy Savings Measures Key Measure Mix % of Total Savings Revise control sequence 21% TRICKs Reduce equipment runtime 15% Focus on: • Large equipment (high Optimize airside economizer 12% horsepower, tonnage, etc) Add/optimize SAT reset 8% • Equipment that runs a lot Add VFD to pump 6% Reduce coil leakage 4% Do a test calculation: Reduce/reset DSP setpoint 4% • Estimate savings and costs Add/optimize optimum 3% • Is the payback reasonable? start/stop Add/optimize CWST reset 2% Source: A Study on Energy Savings and Measure Cost Effectiveness of EBCx, PECI, 2009 Page 49
  • 50. Wrap-up Resources  California Commissioning Collaborative  www.cacx.org  Better Bricks  www.betterbricks.com  Taylor Engineering  www.taylor-engineering.com  Portland Energy Conservation, Inc - PECI  www.peci.org Page 50
  • 51. Wrap-up Conclusion  Trending  Invaluable tool  Identify operational issues  Calculate accurate energy savings (and spreadsheets)  Spreadsheet Calculations  Straightforward  Flexible  Accurate  Worth the investment in development Page 51
  • 53. Energy Saving Calculations for Existing Building Commissioning Gustav Brändström, PE Angela Vreeland, PE February 19, 2013

Editor's Notes

  1. State that we will have some time allotted for questions during the presentation and also at the end, so please reserve your questions for those times.
  2. Interactions between energy saving measures are easily accounted forAHU EBCxSchedule changeRepair leaking valveReduce VAV box minimum flow setpoints
  3. Thank you Gustav. As the agenda shows, we will be discussing two calculations today, one involving airside economizers and one on installing a variable frequency drive on a pump.
  4. Shown here are the top energy saving measures in existing building commissioning from a study conducted by PECI.The measures we will be covering today are starred and we chose these measures because we have encountered them frequently in our work and from our experience, they tend to result in significant energy savings with attractive paybacks.
  5. So I will start by giving some background on economizers- how they are controlled and some common problems they have. Then I will follow that with a specific example of how to calculate savings that result from correcting improper economizer operation.Basically, the purpose of an economizer is to determine the amount of outside air that should be brought in to reduce mechanical cooling and maintain the required ventilation for the people and space served by the air handler.There are four typical ways that economizers are controlled. The control can be based on a fixed drybulb temperature….
  6. A lot of trend data to get this temperature rangeFixed drybulb high limit
  7. Humidity sensors are getting better
  8. So now I’ll go through an example of how to calculate the savings associated with correcting poor economizer operation. So the Finding, or problem, is that….
  9. Here is the entire spreadsheet calculation that was used to determine the savings for this measure. As you can see, it is quite short and simple. I will go through each column and explain how they are calculated. The first group of columns is basically the variables upon which the savings are based and I will discuss them first.
  10. We’ve established the variables that the calculation is based on and next we’ll calculate the current energy use of the AHU and then calculate the energy use after the lockout is reduced to 70F.
  11. We will now calculate the energy use after the lockout is reduced to 70F.
  12. Everything here is the same as the second group of columns we just looked at, except here the outside air damper goes to minimum position when the outside temperature is above 70F. In this case, the minimum is 10%. It is best to figure out the minimum %OA by looking at the %OA at extremely low outside temperatures when the return, mixed, and outside temperatures are very different. This will result in a more accurate %OA.
  13. Here is the entire calculation again, with the changes between the current and proposed cases highlighted in red. All the savings are occurring when the outside air damper is open and economizing, but should be a minimum position.
  14. State the source (even though its at the bottom, just say it as well to give it more credibility)We chose the measures starred here to discuss today. We chose these measures because we have encountered them very frequently in our work and from our experience, they tend to result in significant energy savings with attractive paybacks.
  15. We’re showing the top savings measures again to highlight the importance of focusing on the measures that result in high energy savings. We recommend starting with this list when creating an EBCx plan. In addition, it is good to focus on large equipment, that is, equipment with a high horsepower or tonnage, and equipment that operates a lot. They will use more energy and thus have higher energy savings potential. Also, we highly recommend doing a preliminary calculation before diving into the trend data and creating an in-depth spreadsheet calculation. These “back of the envelope” calculations can save a lot of time. If the equipment that you plan to optimize uses very little energy now, there won’t be much to save. Estimate the costs and savings and see if the payback is reasonable and justifies further analysis. One trap we’d like to point out is to avoid installing VFDs on equipment that is smaller than 10 hp. In our experience, they simply don’t pay off so we don’t recommend them.
  16. Listed here are some of the common resources that we use in our work. The California Commissioning Collaborative and Better Bricks have great resources on New and Existing building commissioning. Taylor Engineering also has some great resources and is the basis for the economizer high limit control I discussed earlier. PECI is also a great resource that we reference frequently.
  17. So in conclusion, we love trend data. It is completely invaluable for the ebcx work that we do. Trend data allows you to identify operational issues that can’t be identified by any other means. It also allows you to calculate energy savings accurately. We also love spreadsheet calculations. They are straightforward. Flexible. Accurate. And definitely worth the time and effort to develop. Our hope is that everyone that watches this webinar today goes back to their desk and tries out the averageifs and countifs functions. They will change your world.