Smart buildings aim to reduce energy consumption and peak demand through advanced controls and monitoring occupancy. Technologies like smart meters, sensors, and automated systems allow more efficient operation based on presence and pricing signals. Case studies show potential for demand response through load shifting and peak shaving. However, measuring efficiency solely based on area or consumption can miss factors like occupation density and operating hours. Advanced metrics accounting for these issues may better indicate actual performance.
6. Definitions
Smart grid:
• Energy supply network that shall charge consumers at a variable
energy price per hour
• Prices shall be varied with demand
• First project in Finland January 2013 (Fortum)
• Kalasatamankeskus first smart grid neighbourhood (Helsingin Energia)
Smart meters:
• Electronic energy meters that record detailed customer data
• the amount of energy consumed and when this energy is
consumed
• Information can be viewed in real-time
10. Electricity Generation
Finnish peak day energy generation: February 2011
40
35
30
% of peak load
25
20
18%
15
10
5
0
Nuclear Power Hydro Power Wind CHP Condensing Nett imports
Energy generation method
11. Electricity Generation
Cost of generation (approximate costs, operation only)
System €/ MWh
Wind 5
Nuclear Power 15
Hydro Power 20
Condensing Coal 25
CHP 38
Nett imports 49
Conventional gas turbine 125
12. Energy Generation
Prices: Electricity is important
Electricity District Heating
2011 84,4 €/MWh 2011 63,9 €/MWh
2020 110,7 €/MWh1 2020 65,8 €/MWh
Change 31,2 % Change 2.9%
1The Finnish electricity price for 2020 has assumed to be equal to the German
electricity price for 2011. The German 2011 price has been taken from a Eurostat
report that showed German energy prices for mid-size industrial companies (500–
2000 MWh)
14. Smart Grid: How to reduce consumption
Energy Reduction Load shifting Peak Shaving
Energy Energy Energy
Time Time Time
Options: Options: Options:
• Renewable energy • Smart appliances • React to energy prices by
turning systems on or off
• Energy reduction • Task scheduling
measures • Reduce internal conditions
• Advanced presence
detection
29. Commercial Buildings:
Peak shaving
• Can we find items to turn off in the middle of the day
• Office staff on holidays, sick, external meetings, sales team
• UK study shows offices on average 45% occupied 2
2: Regus, “Measuring the benefits of agility at work”, May 2011
Energy
• Turn off (where people are missing)
• Lighting
• Ventilation
• Computers
30. Monitoring occupancy
Access control system - measures when people are in the building
Employees log in/out of the building via:
• Electronic time clock
• Smart phone
• Personal computer
• Real time location tags
Building
Location is defined as a set of routines:
OUT IN
• Routine 1: out of the building
• Routine 2: in the building
31. Advanced presence detection
Use presence knowledge to control energy consuming systems
Define location as a set of routines:
• Routine 1: out of the building
• Routine 2: in the building
• Subroutine A: at workspace
• Subroutine B: in a meeting
• Subroutine C: at lunch
Building
OUT IN
OUT IN
OUT IN
32. Use presence to control
Use presence knowledge to control:
• Shut down an individual’s workspace if they leave the building
• Set to standby an individual’s workspace if they are in a meeting / at lunch
• Shut down a lighting / ventilation zone if all of the occupants are out of the office
Example zone control modes:
System Type Presence
Detected
Desk Lighting ON
Common Lighting ON
Equipment ON
Ventilation 100 %
Heating 21oC
Cooling 25oC
33. Use presence to control
Use presence knowledge to control:
• Shut down an individual’s workspace if they leave the building
• Set to standby an individual’s workspace if they are in a meeting / at lunch
• Shut down a lighting / ventilation zone if all of the occupants are out of the office
Example zone control modes:
System Type Presence No presence
Detected 15 mins
Desk Lighting ON OFF
Common Lighting ON ON
Equipment ON STAND BY
Ventilation 100 % 100 %
Heating 21oC 21oC
Cooling 25oC 25oC
34. Use presence to control
Use presence knowledge to control:
• Shut down an individual’s workspace if they leave the building
• Set to standby an individual’s workspace if they are in a meeting / at lunch
• Shut down a lighting / ventilation zone if all of the occupants are out of the office
Example zone control modes:
System Type Presence No presence No presence
Detected 15 mins 1 hour
Desk Lighting ON OFF OFF
Common Lighting ON ON OFF
Equipment ON STAND BY STAND BY
Ventilation 100 % 100 % 50 %
Heating 21oC 21oC 20oC
Cooling 25oC 25oC 27oC
35. Use presence to control
Use presence knowledge to control:
• Shut down an individual’s workspace if they leave the building
• Set to standby an individual’s workspace if they are in a meeting / at lunch
• Shut down a lighting / ventilation zone if all of the occupants are out of the office
Example zone control modes:
System Type Presence No presence No presence No presence 2
Detected 15 mins 1 hour hours
Desk Lighting ON OFF OFF OFF
Common Lighting ON ON OFF OFF
Equipment ON STAND BY STAND BY OFF
Ventilation 100 % 100 % 50 % Night time mode
Heating 21oC 21oC 20oC Night time mode
Cooling 25oC 25oC 27oC Night time mode
36. Concept development
Virtual Energy
Smart Grid
Prices
Advanced
Advanced Presence
Controls Detection
Technology
37. Incentive schemes
Residential building example:
• A block of similar 2 bedroom apartments
• Incentive scheme to reduce energy
• Reward given to the lowest energy consumption
38. Occupation density
Energy directly related to people is not considered by area metrics
Average occupation density in UK offices is 11.8m2 per workspace3
• 77% of workspaces between 8m2 & 13m2 per workspace
• Using kWh/m2, 13m2 per workspace will seem more energy
efficient than 8m2 per workspace
3: Occupier Density Study Summary Report, British Council for Offices, June 2009
Source: Fooducate.com
39. Case study: Occupation density
Simulated case study: office building in Helsinki
• Area: 4650m2
• Hours of occupancy 08:00 – 17:00 (9 hours)
Similar day lengths, different occupation densities
Case A B C
Population density (m2/person) 8 10 12
Number of occupants 500 400 332
Energy consumption (kWh/m2) 102 99 98
Energy consumption (kWh/person) 951 1150 1368
Energy consumption (Wh/m2h) 0.087 0.105 0.126
Results
• kWh/m2: case C consumes the least
• kWh/person or Wh/m2h: case A consumes the least
(C consumes 44% more than A)
40. Hours of occupation
Not considered by area metrics
• Comparison of two similar healthcare buildings
• Hospital ”A” open 24 hrs / Hospital ”B” open 12 hrs
• kWh/m2 does not provide an allowance for the longer day of ”A”
• Thus ”A” has a higher energy consumption per m2 and seems
less energy efficient
41. Case study: Hours of occupation
• Simulated case study: office building in Helsinki
• Area: 4650m2
• Population density 10m2 / person
Similar occupation densities, different day lengths
Case D E F
Working hours per day (h) 12 9 6
Hours of occupancy 08 - 20 08 - 17 09 - 15
Energy consumption (kWh/m2) 115 99 84
Energy consumption (kWh/person) 1330 1150 981
Energy consumption (Wh/m2h) 0.092 0.105 0.134
Results
• kWh/m2: case F consumes the least
• kWh/person or Wh/m2h: case D consumes the least
(F consumes 45% more than D)
42. Concept development
Virtual Energy
Smart Grid
Prices
Advanced
Advanced Presence
Controls Detection
Technology
Measure per Measure
Person Wh/m2h
Behaviour Motivation /
Change Incentives
43. Summary
• Smart grid will bring more efficiency in energy generation
• Cheaper prices on average, but a different way of charging
• People who prepare for smart grid will save money – people who dont
prepare will pay more
• Can we reduce our peak load AND measure energy efficiency more accurately?