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b 3 sustainability Prepared by Alan Richardson August 22, 2011 Prepared by Alan Richardson Stakeholders HVAC Improving ene...
Housekeeping & Course Schedule <ul><li>Our training day </li></ul><ul><li>Start  9:00am </li></ul><ul><li>9.00am – 12.30pm...
Contact and resources <ul><li>Your Trainer </li></ul><ul><li>Login to: </li></ul><ul><ul><li>Password: </li></ul></ul><ul>...
Recognition and Awards <ul><li>National Units of Competency from CPC50210 Diploma of Building and Construction (Building) ...
Stakeholders <ul><li>The Strategic Skills Program (SSP) purchases training from Registered Training Organisations (RTOs) t...
Learning outcomes for today <ul><li>Develop a sustainability policy </li></ul><ul><li>Assess environmental risk </li></ul>...
Our Roadmap <ul><li>Step 1 Vision  </li></ul><ul><li>Step 2 Measure </li></ul><ul><li>Step 3 Manage </li></ul><ul><li>Step...
Learning objective for the course September 22, 2010 Prepared by Alan Richardson
Learning outcomes for the course August 22, 2011 Prepared by Alan Richardson
Learning outcomes cont. September 22, 2010 Prepared by Alan Richardson  Printed on recycled paper
What is sustainability? <ul><li>What is the  triple bottom line  (b 3 )? </li></ul><ul><li>captures an expanded spectrum o...
So where are you at? August 22, 2011 Prepared by Alan Richardson as an individual? as an organisation? Conscious  Competen...
Quiz <ul><li>Facts and figures as supplied by Sydney Water and Energy Australia </li></ul>August 22, 2011 Prepared by Alan...
Australia’ s energy use <ul><li>Source: Total Environment Centre </li></ul>August 22, 2011 Prepared by Alan Richardson
Commercial building energy use <ul><li>HVAC systems account for 30% of energy consumption in Australian commercial buildin...
There is always a stick! <ul><li>Commercial Building Disclosure (CBD) is  
a national program designed to improve the ener...
Consumption vs peak demand <ul><li>What is peak demand? </li></ul><ul><li>used in energy demand management  describing a p...
Do you remember the heatwave week 31 January - 4 Feburary 2011?  <ul><li>The analysis shows that if a typical building wer...
Breakdown of an electricity bill <ul><li>Calculating the real cost of energy </li></ul><ul><li>Peak charges: 8.72 c/kWh </...
Building peak demand versus NABERS Energy ratings for 25 Sydney office buildings <ul><li>The analysis shows that if a typi...
Energy costs forecasted <ul><li>The graph details the cost and escalation rates for retail electricity prices forecasted f...
Australia ’s marginal abatement cost curve Low cost High cost Source: ClimateWorks
Australian building’s marginal abatement cost curve Low cost options High cost options Source: ClimateWorks
What is HVAC? <ul><li>Heating, ventilation and air conditioning (HVAC) </li></ul><ul><li>HVAC systems in commercial buildi...
Central HVAC Air Handling Unit (AHU) AHU Chiller HWS Building Management System Cooling tower Diffuser Outside air intake ...
Central HVAC Air Handling Unit (AHU) AHU Chiller HWS Building Management System Cooling tower Diffuser How the cooling cyc...
Self contained packaged HVAC August 22, 2011
Why energy efficiency in HVAC? <ul><li>Cooling and heating are major contributors to peak demand for energy, they contribu...
What is your approach to energy efficiency? <ul><li>Avoid </li></ul><ul><li>Reduce </li></ul><ul><li>Reuse </li></ul><ul><...
Energy efficiency opportunities in HVAC <ul><li>Recommissioning HVAC system </li></ul><ul><li>Mixed mode ventilation  </li...
Barriers to implementation <ul><li>High capital cost </li></ul><ul><li>Implementation can be complex if a whole HVAC syste...
Drivers for energy efficiency decisions in large tenanted commercial buildings  August 22, 2011 Prepared by Alan Richardso...
Decision making <ul><li>‘ By understanding the human psychology of choice and decision-making, the industry can identify t...
What to do and when?  Source:
Financing options available to fund energy efficiency opportunities <ul><li>Low Carbon Australia </li></ul><ul><li>http://...
Financing options available to fund energy efficiency opportunities <ul><li>Low Carbon Australia </li></ul><ul><li>http://...
Financing options available to fund energy efficiency opportunities <ul><li>Low Carbon Australia </li></ul><ul><li>http://...
Funding energy efficiency opportunities <ul><li>Tax Breaks for Green Buildings </li></ul><ul><li>http://www.thefifthestate...
Energy efficiency opportunities in HVAC <ul><li>Recommissioning HVAC system </li></ul><ul><li>Mixed mode ventilation  </li...
Upgrade HVAC control system using Direct Digital Control (DDC)  <ul><li>Controlling a HVAC system involves three distinct ...
Upgrade HVAC control system using Direct Digital Control (DDC)  <ul><li>Controlling a HVAC system involves three distinct ...
Upgrade Building Management System (BMS) to Energy Management System (EMS) <ul><li>Upgrades to Building Management System ...
Mixed mode ventilation <ul><li>Mixed mode ventilation </li></ul><ul><li>Combination of  a combination of natural ventilati...
Reducing electrical loads <ul><li>Reducing electrical loads </li></ul><ul><li>Adjust set points </li></ul><ul><ul><li>Set ...
Players comfort? <ul><li>Reducing electrical loads </li></ul><ul><li>‘ The static (1 o C) setpoint increase produced a 6% ...
What is a deadband control strategy? <ul><li>Reducing electrical loads </li></ul><ul><li>A deadband is a range where no ac...
What are the energy savings from a deadband control strategy? <ul><li>Reducing electrical loads </li></ul><ul><li>A standa...
What is the best deadband range? <ul><li>Reducing electrical loads </li></ul><ul><li>Generally accepted practice is to hav...
Economy cycle and  free cooling <ul><li>Enthalpy optimisation </li></ul><ul><li>There are energy savings if the cooling co...
Economy cycle and  free cooling <ul><li>The economy cycle operation uses fresh air for building cooling, instead of the ch...
Economy cycle and  free cooling <ul><li>Enthalpy optimisation </li></ul><ul><li>There are energy savings if the cooling co...
Economy cycle and  free cooling <ul><li>Enthalpy optimisation </li></ul><ul><li>More info: </li></ul><ul><li>http://www.se...
Economiser <ul><li>Enthalpy optimisation </li></ul><ul><li>There are energy savings if the cooling coil is presented with ...
Economiser <ul><li>When temperatures are hot or cold outside with high occupancy inside, 100% outside air passes through t...
Demand control ventilation <ul><li>CO2 sensors monitor the space and provide minimum Outside Air in times of low occupancy...
Night purge <ul><li>Reduce electrical loads </li></ul><ul><li>During the cooling season, if the inside temperature is cons...
Night purge <ul><li>Reduce electrical loads </li></ul><ul><li>However, caution should be taken concerning the humidity of ...
Other change practices to reduce peak demand <ul><li>Other change practices to reduce peak demand </li></ul><ul><li>Demand...
Variable speed drives (VSDs) <ul><li>Upgrades to fans and pumps </li></ul><ul><li>More info: </li></ul><ul><li>http://www....
Variable speed drives (VSDs) <ul><li>Upgrades to fans and pumps </li></ul><ul><li>More info: </li></ul><ul><li>http://www....
What are the energy savings from VSDs? <ul><li>Upgrades to fans and pumps </li></ul><ul><li>More info: </li></ul><ul><li>h...
Maintenance <ul><li>Maintenance </li></ul><ul><li>Check for and repair leaks in ductwork </li></ul><ul><li>Check insulatio...
Chiller upgrade  <ul><li>Efficient chillers </li></ul><ul><li>http://www.powerpax.com.au/casestudies </li></ul><ul><li>Ref...
Chiller upgrade case study <ul><li>Efficient chillers </li></ul><ul><li>http://www.powerpax.com.au/casestudies </li></ul><...
References <ul><li>ABARES 2011,  Energy Update 2011 , Accessed at <  http://adl.brs.gov.au/data/warehouse/pe_abares9901061...
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HVAC Energy Efficiency in Commercial Buildings

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HVAC Energy Efficiency in Commercial Buildings

  1. 1. b 3 sustainability Prepared by Alan Richardson August 22, 2011 Prepared by Alan Richardson Stakeholders HVAC Improving energy efficiency in existing non-residential buildings
  2. 2. Housekeeping & Course Schedule <ul><li>Our training day </li></ul><ul><li>Start 9:00am </li></ul><ul><li>9.00am – 12.30pm </li></ul><ul><li>LUNCH </li></ul><ul><li>1.00pm – 4.00pm </li></ul><ul><li>Finish 4:00pm </li></ul>August 22, 2011 Prepared by Alan Richardson
  3. 3. Contact and resources <ul><li>Your Trainer </li></ul><ul><li>Login to: </li></ul><ul><ul><li>Password: </li></ul></ul><ul><li>Send email and assessments to: </li></ul><ul><li>Download slides, tools and templates and resources from: </li></ul><ul><li>To stay current with online conversations use this RSS feed: </li></ul>August 22, 2011 Prepared by Alan Richardson
  4. 4. Recognition and Awards <ul><li>National Units of Competency from CPC50210 Diploma of Building and Construction (Building) </li></ul><ul><li>Statements of Attainment issued by the The building Institute of Training and Development </li></ul><ul><li>RTO No. 91145 </li></ul><ul><li>Participants who successfully complete this course will be awarded Statements of Attainment in the following Units of Competency: </li></ul><ul><ul><li>CPCSUS5001A Develop workplace policies and procedures for sustainability </li></ul></ul><ul><ul><li>CPCCBC5012A Manage the application and monitoring of energy conservation and management practices and processes </li></ul></ul><ul><ul><li>BSBMGT515A Manage operational plan </li></ul></ul>September 22, 2010 Prepared by Alan Richardson Printed on recycled paper
  5. 5. Stakeholders <ul><li>The Strategic Skills Program (SSP) purchases training from Registered Training Organisations (RTOs) to address the strategic skill needs of industry, community and individuals. </li></ul><ul><li>The Building Institute of Training and Development </li></ul><ul><li>NSW Department of Education and Training – Strategic Skills Program </li></ul><ul><li>NSW Office of Energy and Heritage- Sustainability Advantage Energy Saver Program </li></ul>September 22, 2010 Prepared and delivered by Alan Richardson – The Building Institute of Training and Development. Printed on recycled paper
  6. 6. Learning outcomes for today <ul><li>Develop a sustainability policy </li></ul><ul><li>Assess environmental risk </li></ul><ul><li>Analyse current energy, water and waste use </li></ul><ul><li>Benchmark current sustainability performance against industry standards </li></ul><ul><li>Set sustainability objectives and targets to reduce energy, water and water use </li></ul>September 22, 2010 Prepared by Alan Richardson
  7. 7. Our Roadmap <ul><li>Step 1 Vision </li></ul><ul><li>Step 2 Measure </li></ul><ul><li>Step 3 Manage </li></ul><ul><li>Step 4 Mitigate </li></ul><ul><li>Step 5 Verify (Measure) </li></ul>August 22, 2011 Prepared by Alan Richardson Today
  8. 8. Learning objective for the course September 22, 2010 Prepared by Alan Richardson
  9. 9. Learning outcomes for the course August 22, 2011 Prepared by Alan Richardson
  10. 10. Learning outcomes cont. September 22, 2010 Prepared by Alan Richardson Printed on recycled paper
  11. 11. What is sustainability? <ul><li>What is the triple bottom line (b 3 )? </li></ul><ul><li>captures an expanded spectrum of values and criteria for measuring organisational (and societal) success: economic, ecological and social </li></ul>September 22, 2010 Prepared and delivered by Alan Richardson – The Building Institute of Training and Development. Printed on recycled paper
  12. 12. So where are you at? August 22, 2011 Prepared by Alan Richardson as an individual? as an organisation? Conscious Competent Unconscious Not Yet Competent Unconscious Competent Conscious Not Yet Competent
  13. 13. Quiz <ul><li>Facts and figures as supplied by Sydney Water and Energy Australia </li></ul>August 22, 2011 Prepared by Alan Richardson One tonne of CO2e emitted by a coal fired power plant is equivalent to how many kWh of electricity? How many tonnes of CO2e per year does an average sized family car emit? What is the recommended flow rate of water for a household shower? How may Litres (L) does an Olympic swimming pool hold when full? What is the measure of instantaneous electrical load? When we want to express the amount of electrical energy used over a period of time we express it as kilowatt hours (kWh). How many 20 Watt light bulbs burning for one hour will consume 1,000 kWh of electricity?
  14. 14. Australia’ s energy use <ul><li>Source: Total Environment Centre </li></ul>August 22, 2011 Prepared by Alan Richardson
  15. 15. Commercial building energy use <ul><li>HVAC systems account for 30% of energy consumption in Australian commercial buildings </li></ul><ul><li>Commercial sector about 300PJ or 8% of final energy use in Australia (ABARES 2011), and 200PJ of electricity use (Langham et al 2010) </li></ul>August 22, 2011 Prepared by Alan Richardson
  16. 16. There is always a stick! <ul><li>Commercial Building Disclosure (CBD) is  
a national program designed to improve the energy efficiency of Australia’s large office buildings </li></ul><ul><li>http://www.cbd.gov.au/default.aspx </li></ul><ul><li>Section J of the Building Code of Australia </li></ul><ul><ul><li>Deals with energy efficiency requirements of BCA class 3 to 9 buildings </li></ul></ul><ul><li>National Greenhouse and Energy Reporting (NGER) Act 200 </li></ul><ul><li>Building Energy Efficiency Disclosure Act 2010 </li></ul><ul><ul><ul><li>October 2011 all prospective tenants or buyers must be provided with a Building Energy Efficiency Certificate (BEEC), valid for one year, and summarises the performance of the building, including the efficiency of lighting in the building </li></ul></ul></ul>August 22, 2011 Prepared by Alan Richardson
  17. 17. Consumption vs peak demand <ul><li>What is peak demand? </li></ul><ul><li>used in energy demand management  describing a period in which electrical power is expected to be provided for a sustained period at a significantly higher than average supply level </li></ul><ul><li>‘ large electricity customers pay about 13% of their bills to cover peak capacity charges each year, and a further 32% to cover network energy charges. That ’ s around $150,000 per year in peak demand charges and $350,000 in network energy charges for the largest of CBD buildings. So any peak demand reduction also means lower energy expenditure ’ </li></ul><ul><li>Peak demand tackled by Greener Buildings. Green Buildings Alive </li></ul>August 22, 2011 Prepared by Alan Richardson
  18. 18. Do you remember the heatwave week 31 January - 4 Feburary 2011? <ul><li>The analysis shows that if a typical building were to be upgraded from the Sydney average of 2.5 stars to 5 stars, a 57% reduction in electricity consumption would be achieved with a corresponding reduction in peak demand of 26%. This study implies that for every 10% reduction in buildings’ yearly electricity consumption they make a 4.5% reduction in their peak demand. </li></ul>Peak demand 12pm – 4pm Source: www.greenbuildingsalive.com/blog
  19. 19. Breakdown of an electricity bill <ul><li>Calculating the real cost of energy </li></ul><ul><li>Peak charges: 8.72 c/kWh </li></ul><ul><li>Off-peak charges: 4.02 c/kWh </li></ul><ul><li>Average charge: 7.31 c/kWh </li></ul>August 22, 2011 Prepared by Alan Richardson Typical cost Energy Peak 6 c/kWh Off peak 3 c/kWh Network Network peak 2.5 c/kWh Network off peak 0.8 c/kWh Network standing charge - Demand $6/ kW-month Other E&REC - MRET 0.1 c/kWh NEMCO ancillary 0.07 c/kWh NEMCO pool fees 0.05 c/kWh Meter provision $900 pa Retail service fee -
  20. 20. Building peak demand versus NABERS Energy ratings for 25 Sydney office buildings <ul><li>The analysis shows that if a typical building were to be upgraded from the Sydney average of 2.5 stars to 5 stars, a 57% reduction in electricity consumption would be achieved with a corresponding reduction in peak demand of 26%. This study implies that for every 10% reduction in buildings’ yearly electricity consumption they make a 4.5% reduction in their peak demand. </li></ul>August 22, 2011 Prepared by Alan Richardson Source: www.greenbuildingsalive.com/blog
  21. 21. Energy costs forecasted <ul><li>The graph details the cost and escalation rates for retail electricity prices forecasted for the next 15 years </li></ul>August 22, 2011 Prepared by Alan Richardson Source: The Road To Green Property by Davis Langdon
  22. 22. Australia ’s marginal abatement cost curve Low cost High cost Source: ClimateWorks
  23. 23. Australian building’s marginal abatement cost curve Low cost options High cost options Source: ClimateWorks
  24. 24. What is HVAC? <ul><li>Heating, ventilation and air conditioning (HVAC) </li></ul><ul><li>HVAC systems in commercial buildings add or remove heat and moisture (humidity) to maintain environmental conditions </li></ul><ul><li>Also filter and recirculate air to remove odour, dust and other particulates to provide acceptable standards in air quality </li></ul><ul><li>A Building Management System (BMS) controls operation of HVAC system components: fans, pumps, chiller heater (boiler) and cooling tower </li></ul>August 22, 2011 Prepared by Alan Richardson
  25. 25. Central HVAC Air Handling Unit (AHU) AHU Chiller HWS Building Management System Cooling tower Diffuser Outside air intake Pumps with VSDs Heating coil Cooling coil Variable Speed Drive VSD VSD AHU Air Handling Unit (AHU) Variable Air Valve (VAV)
  26. 26. Central HVAC Air Handling Unit (AHU) AHU Chiller HWS Building Management System Cooling tower Diffuser How the cooling cycle in a central HVAC system Pumps with VSDs Heating coil Cooling coil Variable Speed Drive VSD VSD AHU AHU
  27. 27. Self contained packaged HVAC August 22, 2011
  28. 28. Why energy efficiency in HVAC? <ul><li>Cooling and heating are major contributors to peak demand for energy, they contribute disproportionately to energy bills, which increasingly include extra charges for high energy demand not only consumption </li></ul><ul><li>Cooling requirement is a higher % than heating as a building ’ s heat requirement is offset by waste heat? </li></ul><ul><li>Waste heat: people, computers etc </li></ul>
  29. 29. What is your approach to energy efficiency? <ul><li>Avoid </li></ul><ul><li>Reduce </li></ul><ul><li>Reuse </li></ul><ul><li>Renewable </li></ul>August 22, 2010 Prepared by Alan Richardson Does this sound similar to how organisations manage OHS risk?
  30. 30. Energy efficiency opportunities in HVAC <ul><li>Recommissioning HVAC system </li></ul><ul><li>Mixed mode ventilation </li></ul><ul><li>Upgrades to HVAC control system </li></ul><ul><li>Reducing electrical loads </li></ul><ul><li>Enthalpy optimisation </li></ul><ul><li>Change practices to reduce peak demand </li></ul><ul><li>Upgrades to fans and pumps </li></ul><ul><li>Upgrades to cooling and heating plant </li></ul><ul><li>Maintenance </li></ul>August 22, 2011 Prepared by Alan Richardson
  31. 31. Barriers to implementation <ul><li>High capital cost </li></ul><ul><li>Implementation can be complex if a whole HVAC system upgrade is necessary </li></ul><ul><li>Upgrading key components i.e. chiller plant in a building will require the partially shut down of that activity for a period of time </li></ul><ul><li>Existing leases </li></ul><ul><li>Re-negotiating leases </li></ul>August 22, 2011 Prepared by Alan Richardson
  32. 32. Drivers for energy efficiency decisions in large tenanted commercial buildings August 22, 2011 Prepared by Alan Richardson Source: ClimateWorks
  33. 33. Decision making <ul><li>‘ By understanding the human psychology of choice and decision-making, the industry can identify the greatest barriers inhibiting change, discover opportunities for improvement; adopt new methods of communication and design programs that are in line with consumer demands ’ </li></ul><ul><li>Source: 2011 IBM Global Utility Consumer Survey </li></ul>August 22, 2011 Prepared by Alan Richardson
  34. 34. What to do and when? Source:
  35. 35. Financing options available to fund energy efficiency opportunities <ul><li>Low Carbon Australia </li></ul><ul><li>http://www.lowcarbonaustralia.com.au/page/financial-products-and-services </li></ul><ul><li>Low Carbon Australia ’ s Energy Efficiency Program provides finance and advice to businesses looking to invest in the energy efficiency retrofits of existing non-residential buildings: </li></ul><ul><li>Clean Energy Loans  – to finance improvements which deliver energy and carbon savings for the benefits of building owners and tenants </li></ul><ul><li>Energy Efficiency Leases  – to help overcome constraints to businesses of providing up front capital for energy efficiency equipment, offers owners and tenants the flexibility to upgrade as technology evolves and improves and removes from the lessee residual value risk of the asset </li></ul>August 22, 2011 Prepared by Alan Richardson
  36. 36. Financing options available to fund energy efficiency opportunities <ul><li>Low Carbon Australia </li></ul><ul><li>http://www.lowcarbonaustralia.com.au/page/financial-products-and-services </li></ul><ul><li>Low Carbon Australia ’ s Energy Efficiency Program provides finance and advice to businesses looking to invest in the energy efficiency retrofits of existing non-residential buildings: </li></ul><ul><li>Energy Savings Guarantee On-bill financing  – enables businesses to install and upgrade energy efficiency equipment, financed by a utility, with repayments made by the business through their monthly utility bill. This removes the requirement for upfront capital for energy efficiency equipment, with repayments typically equal to or less than the energy cost savings achieved </li></ul>August 22, 2011 Prepared by Alan Richardson
  37. 37. Financing options available to fund energy efficiency opportunities <ul><li>Low Carbon Australia </li></ul><ul><li>http://www.lowcarbonaustralia.com.au/page/financial-products-and-services </li></ul><ul><li>Low Carbon Australia ’ s Energy Efficiency Program provides finance and advice to businesses looking to invest in the energy efficiency retrofits of existing non-residential buildings: </li></ul><ul><li>Environmental Upgrade Agreements (EUAs)  – an agreement between a building owner, a finance provider and a council which allows building owners to access finance for environmental upgrades to their building. Repayments are structured through a council levy on the property, with the council then forwarding on payments to the finance provider. EUA’s overcome difficulties for building owners in providing upfront capital and allow for structured payments that remain with the property if ownership changes. Building owners may also pass on repayment costs to tenants who can benefit from reduced energy costs and a more environmentally efficient workplace </li></ul>August 22, 2011 Prepared by Alan Richardson
  38. 38. Funding energy efficiency opportunities <ul><li>Tax Breaks for Green Buildings </li></ul><ul><li>http://www.thefifthestate.com.au/archives/21194 </li></ul><ul><li>Green Building Fund </li></ul><ul><li>http://www.ausindustry.gov.au/InnovationandRandD/GreenBuildingFund/Pages/GreenBuildingFund.aspx </li></ul><ul><li>Tax Breaks for Green Buildings </li></ul><ul><ul><li>From 1 July 2012, businesses that invest in eligible assets or capital works to improve the energy efficiency of their existing buildings (from 2 stars or lower to at least 4 stars) may be able to apply for a one-off bonus tax deduction. The incentive will enable businesses to claim a bonus tax deduction of 50% of the cost of the eligible assets or capital works. This initiative is expected to provide a boost of around $1 billion over the life of the scheme to help ‘green up’ existing buildings across the country </li></ul></ul><ul><li>Green Building Fund </li></ul><ul><ul><li>Round 7 of the  Green Building Fund  closed on 29 March 2011 </li></ul></ul>August 22, 2011 Prepared by Alan Richardson
  39. 39. Energy efficiency opportunities in HVAC <ul><li>Recommissioning HVAC system </li></ul><ul><li>Mixed mode ventilation </li></ul><ul><li>Upgrades to HVAC control system </li></ul><ul><li>Reducing electrical loads </li></ul><ul><li>Enthalpy optimisation </li></ul><ul><li>Change practices to reduce peak demand </li></ul><ul><li>Upgrades to fans and pumps </li></ul><ul><li>Upgrades to cooling and heating plant </li></ul><ul><li>Maintenance </li></ul>August 22, 2011 Prepared by Alan Richardson
  40. 40. Upgrade HVAC control system using Direct Digital Control (DDC) <ul><li>Controlling a HVAC system involves three distinct steps: </li></ul><ul><li>1) Measure a variable and collect data </li></ul><ul><li>2) Process the data with other information </li></ul><ul><li>3) Cause a control action </li></ul><ul><li>The above three functions are met through sensor, controller and the controlled device </li></ul><ul><li>Direct Digital Control  (DDC) is the automated control of a condition or process by a digital device </li></ul><ul><li>The benefit of DDC over past control technologies (pneumatic or distributed electronic) is that it improves the control effectiveness and increases the control efficiency </li></ul><ul><li>‘ The DDC system is the &quot;brain&quot; of the HVAC system. It dictates the position of every damper and valve in a system. It determines which fans, pumps and chiller run and at what speed or capacity. With this configurable intelligency in this &quot;brain&quot;, we are moving to the concept of building automation ’ Wikipedia </li></ul>August 22, 2011 Prepared by Alan Richardson
  41. 41. Upgrade HVAC control system using Direct Digital Control (DDC) <ul><li>Controlling a HVAC system involves three distinct steps: </li></ul><ul><li>1) Measure a variable and collect data </li></ul><ul><li>2) Process the data with other information </li></ul><ul><li>3) Cause a control action </li></ul><ul><li>The above three functions are met through sensor, controller and the controlled device </li></ul><ul><li>Upgrading HVAC control system to DDC has potential to improve energy efficiency by up to 20% </li></ul><ul><ul><ul><li>Most subsystems, from Variable Air Valve (VAV) boxes to boilers and chillers, now have an onboard DDC system to optimise the performance of that unit. A communication protocol known as BACNet is a standard protocol that allows control units from different manufacturers to pass data to each other </li></ul></ul></ul>August 22, 2011 Prepared by Alan Richardson
  42. 42. Upgrade Building Management System (BMS) to Energy Management System (EMS) <ul><li>Upgrades to Building Management System (BMS) for increased control and optimisation HVAC system operation </li></ul><ul><li>Energy Management System (EMS) is a computer based energy monitoring and optimal control system for building services </li></ul><ul><li>Conventional BMS can be upgraded to EMS providing greater and optimal control for: </li></ul><ul><ul><li>HVAC, chillers, pumps, cooling towers, boilers and energy demand </li></ul></ul><ul><li>EMS has potential to improve energy efficiency between 20-50% for HVAC and chillers </li></ul>August 22, 2011 Prepared by Alan Richardson
  43. 43. Mixed mode ventilation <ul><li>Mixed mode ventilation </li></ul><ul><li>Combination of a combination of natural ventilation from operable windows and mechanical HVAC </li></ul><ul><li>Key to mixed mode ventilation is that an educated tenant can have big impact on energy use </li></ul><ul><li>Study shows individuals are more tolerant of temperatures when they feel they have control </li></ul><ul><li>Suggested strategy: </li></ul><ul><ul><li>19-26°C temperature band with natural ventilation </li></ul></ul><ul><ul><li>A/C off when ambient temperature within band </li></ul></ul>August 22, 2011 Prepared by Alan Richardson
  44. 44. Reducing electrical loads <ul><li>Reducing electrical loads </li></ul><ul><li>Adjust set points </li></ul><ul><ul><li>Set thermostats at 25°C for cooling in the summer and 18°C for heating in the winter </li></ul></ul><ul><ul><li>Implement a deadband control strategy </li></ul></ul><ul><li>Optimal start time of HVAC </li></ul><ul><ul><li>Normally pre-cooling/heating time is pre-set </li></ul></ul><ul><ul><li>Can change to be a function of ambient temperature </li></ul></ul><ul><ul><ul><li>Hot day: longer pre-cooling time </li></ul></ul></ul><ul><ul><ul><li>Mild day: shorter pre-cooling time </li></ul></ul></ul><ul><li>Turn outside air off during pre-cool/pre-heat </li></ul>August 22, 2011 Prepared by Alan Richardson
  45. 45. Players comfort? <ul><li>Reducing electrical loads </li></ul><ul><li>‘ The static (1 o C) setpoint increase produced a 6% reduction in daily HVAC electricity consumption. The dynamic approach produced savings of 1.4%, however it was not operational until autumn 2010. This limited our ability to directly compare the two approaches. It was found that occupant comfort, quantified by frequency of ‘ complaints ’ registered with a tenant helpdesk, was adversely affected under both strategies . ’ </li></ul><ul><li>A preliminary evaluation of two strategies for raising indoor air temperature setpoints in office buildings. By Craig Roussac Jesse Steinfeld and Richard de Dear </li></ul>August 22, 2011 Prepared by Alan Richardson
  46. 46. What is a deadband control strategy? <ul><li>Reducing electrical loads </li></ul><ul><li>A deadband is a range where no action occurs (the system is dead) </li></ul><ul><li>The larger the deadband the less the major energy consuming elements of the HVAC need to work (chillers, hot water service) </li></ul><ul><li>The big advantage of a wide range is that it stops the conflicting systems ‘ hunting ’ ie. heating up, then cooling, then heating, then cooling, etc </li></ul><ul><li>a widening of temperature dead bands has been more effective than pretty much every other HVAC strategy (apart from turning it off) </li></ul>August 22, 2011 Prepared by Alan Richardson
  47. 47. What are the energy savings from a deadband control strategy? <ul><li>Reducing electrical loads </li></ul><ul><li>A standard approximate for energy savings would be something like the figures below: </li></ul><ul><ul><li>Bottom of range – actual set point – top of range </li></ul></ul><ul><ul><li>22 o - 22.5 o – 23 o (0.5 degree) normal 0% energy saving </li></ul></ul><ul><ul><li>21 o - 22.5 o – 24 o (1.5 degree either side) 10% energy saving </li></ul></ul><ul><ul><li>20 o - 22.5 o – 25 o (2.5 degree either side) 20% energy saving </li></ul></ul>August 22, 2011 Prepared by Alan Richardson
  48. 48. What is the best deadband range? <ul><li>Reducing electrical loads </li></ul><ul><li>Generally accepted practice is to have a deadband of between 21 - 24 o C where in summer system will keep temp at 24 o C but not try to push down below 22.5 o C and in winter keep temperature at 21 o C and not try to push past 22.5 o C </li></ul>August 22, 2011 Prepared by Alan Richardson
  49. 49. Economy cycle and free cooling <ul><li>Enthalpy optimisation </li></ul><ul><li>There are energy savings if the cooling coil is presented with the air having the lower enthalpy whether this is return air or outside air </li></ul>August 22, 2011 Prepared by Alan Richardson Source: www.energystar.gov Return air, damper closed, becomes exhaust air Air Handling Unit (AHU) 100% outside air No heating or cooling of outside air
  50. 50. Economy cycle and free cooling <ul><li>The economy cycle operation uses fresh air for building cooling, instead of the chiller when outside conditions permit. In addition to providing free cooling , when outside conditions are suitable, economy cycle operation increases the amount of fresh air in the conditioned space </li></ul>August 22, 2011 Prepared by Alan Richardson Source: www.energystar.gov Return air, damper closed, becomes exhaust air Air Handling Unit (AHU) 100% outside air No heating or cooling of outside air
  51. 51. Economy cycle and free cooling <ul><li>Enthalpy optimisation </li></ul><ul><li>There are energy savings if the cooling coil is presented with the air having the lower enthalpy whether this is return air or outside air </li></ul><ul><li>More info: </li></ul><ul><li>Retro-fitting an economy cycle depends on: </li></ul><ul><ul><li>Capacity of Air Handling Units (AHUs) </li></ul></ul><ul><ul><li>Fresh air supply duct size </li></ul></ul><ul><ul><li>Type of HVAC control system – at minimum use DDC and enthalpy based control </li></ul></ul><ul><li>There are two types of economy cycles: temperature OR enthalpy based </li></ul><ul><li>Enthalpy based economy cycle provides better control = greater energy savings </li></ul><ul><li>Cost $POA </li></ul>August 22, 2011 Prepared by Alan Richardson
  52. 52. Economy cycle and free cooling <ul><li>Enthalpy optimisation </li></ul><ul><li>More info: </li></ul><ul><li>http://www.seav.vic.gov.au/manufacturing/sustainable_manufacturing/resource.asp?action=show_resource&resourcetype=2&resourceid=32 </li></ul><ul><li>Enthalpy is determined by a combination of temperature and relative humidity </li></ul><ul><li>If economy cycle fitted then check the operation as follows: </li></ul><ul><ul><li>Is the controller functional? </li></ul></ul><ul><ul><li>Is the controller calibrated? </li></ul></ul><ul><li>There are two types of economy cycles: </li></ul><ul><ul><li>Temperature based </li></ul></ul><ul><ul><li>Enthalpy based </li></ul></ul><ul><li>Enthalpy based economy cycle provides greater control = greater energy savings </li></ul>August 22, 2011 Prepared by Alan Richardson
  53. 53. Economiser <ul><li>Enthalpy optimisation </li></ul><ul><li>There are energy savings if the cooling coil is presented with the air having the lower enthalpy, whether this is return air or outside air </li></ul><ul><li>In simple terms, an economiser is a heat exchanger </li></ul><ul><li>An air-to-air heat exchanger, inside AHU, uses cooler or warmer return air (summer/winter), to pre-cool or pre-heat the incoming outside air </li></ul><ul><li>There is no cross contamination of air paths </li></ul><ul><li>Economisers perform best in cold temperate climates but not hot and humid climates </li></ul><ul><li>Can be retrofitted to ducted a/c systems </li></ul><ul><li>Packaged systems must be purchased with economiser option </li></ul>August 22, 2011 Prepared by Alan Richardson
  54. 54. Economiser <ul><li>When temperatures are hot or cold outside with high occupancy inside, 100% outside air passes through the heat exchanger which reduces the fresh air energy load through pre-conditioning the outdoor air </li></ul><ul><li>Used to cool the fresh air by exhaust air with an air-to-air heat exchanger </li></ul>August 22, 2011 Prepared by Alan Richardson Source: http://www.airchange.com.au/
  55. 55. Demand control ventilation <ul><li>CO2 sensors monitor the space and provide minimum Outside Air in times of low occupancy to conserve energy </li></ul>August 22, 2011 Prepared by Alan Richardson Source: http://www.airchange.com.au/
  56. 56. Night purge <ul><li>Reduce electrical loads </li></ul><ul><li>During the cooling season, if the inside temperature is considerably greater than the outside air temperature, then the air handling units may be turned ON during the night, to purge the warm air out of the building. This is called a Night Purge Cycle. This type of free cooling reduces the amount of mechanical cooling that has to take place the following morning. </li></ul>August 22, 2011 Prepared by Alan Richardson
  57. 57. Night purge <ul><li>Reduce electrical loads </li></ul><ul><li>However, caution should be taken concerning the humidity of the outside air. To address this concern, an enthalpy optimisation program </li></ul><ul><li>Whether or not to use the night purge cycle is determined by comparing the cost of running the air handling units at night versus the cost of running the mechanical cooling in the morning </li></ul>August 22, 2011 Prepared by Alan Richardson
  58. 58. Other change practices to reduce peak demand <ul><li>Other change practices to reduce peak demand </li></ul><ul><li>Demand limiting </li></ul><ul><ul><li>switch off equipment as the electrical use approaches the peak load time. BMS programmed with a priority list of non-critical items to be turned off, simply follows the list until the energy use curve is levelled off and the peak load passes </li></ul></ul><ul><li>Load levelling </li></ul><ul><ul><li>Operating times of other energy using activities shifted outside peak demand period of HVAC operation </li></ul></ul><ul><li>Peak load shifting </li></ul><ul><ul><li>E .g.run the chillers during the night to chill water that is stored in large tanks on the premises. During the peak building load the following day the chillers are turned off and the ready-made chilled water is circulated to the building loop </li></ul></ul>August 22, 2011 Prepared by Alan Richardson
  59. 59. Variable speed drives (VSDs) <ul><li>Upgrades to fans and pumps </li></ul><ul><li>More info: </li></ul><ul><li>http://www.seav.vic.gov.au/manufacturing/sustainable_manufacturing/resource.asp?action=show_resource&resourcetype=2&resourceid=31 </li></ul><ul><li>http://www05.abb.com/global/scot/scot201.nsf/veritydisplay/cd6d14453239c791c125750800332bd2/$file/Energy_efficiency_makes_difference_191108.pdf </li></ul>August 22, 2011 Prepared Alan Richardson
  60. 60. Variable speed drives (VSDs) <ul><li>Upgrades to fans and pumps </li></ul><ul><li>More info: </li></ul><ul><li>http://www.seav.vic.gov.au/manufacturing/sustainable_manufacturing/resource.asp?action=show_resource&resourcetype=2&resourceid=31 </li></ul><ul><li>http://www05.abb.com/global/scot/scot201.nsf/veritydisplay/cd6d14453239c791c125750800332bd2/$file/Energy_efficiency_makes_difference_191108.pdf </li></ul><ul><li>HVAC components such as fans and pumps have traditionally used constant speed drives (motors) </li></ul><ul><li>Variable speed drives allow fans and pumps to modify the speed they operate to match the load that is put on them </li></ul><ul><li>Require less maintenance </li></ul><ul><li>Variable speed drives are one of the biggest and most economically viable energy saving opportunities in HVAC systems for supply and return air fans, chilled and condenser water pumps and chiller compressors </li></ul>August 22, 2011 Prepared Alan Richardson
  61. 61. What are the energy savings from VSDs? <ul><li>Upgrades to fans and pumps </li></ul><ul><li>More info: </li></ul><ul><li>http://www.seav.vic.gov.au/manufacturing/sustainable_manufacturing/resource.asp?action=show_resource&resourcetype=2&resourceid=31 </li></ul><ul><li>http://www05.abb.com/global/scot/scot201.nsf/veritydisplay/cd6d14453239c791c125750800332bd2/$file/Energy_efficiency_makes_difference_191108.pdf </li></ul><ul><li>VSDs on fans and pumps </li></ul><ul><ul><li>Supply and return air fans </li></ul></ul><ul><ul><li>Chilled and condenser water pumps </li></ul></ul><ul><ul><li>Chiller compressors </li></ul></ul><ul><li>Variable-speed motor drives: $3,000 to $5,000 each (installed) </li></ul><ul><li>Savings vary – EPA study on VSDs showed average annual energy savings of 52% of pump/fan energy and 2.5 year simple payback </li></ul>August 22, 2011 Prepared Alan Richardson
  62. 62. Maintenance <ul><li>Maintenance </li></ul><ul><li>Check for and repair leaks in ductwork </li></ul><ul><li>Check insulation of heating and cooling pipework and ductwork </li></ul><ul><li>Check for faulty/frozen dampers </li></ul>August 22, 2011 Prepared Alan Richardson
  63. 63. Chiller upgrade <ul><li>Efficient chillers </li></ul><ul><li>http://www.powerpax.com.au/casestudies </li></ul><ul><li>Refurbishment relevance: Especially for ~1980s buildings due for upgrade </li></ul><ul><li>Life service of chiller: 20-25 years </li></ul><ul><li>Operating costs over lifetime greatly exceed initial cost </li></ul><ul><li>Can double or more the efficiency from old chiller to new high-efficiency chiller, plus improved part load performance </li></ul><ul><li>Require existing chiller load profile to estimate potential savings from new chiller, also maintenance costs should be factored </li></ul>August 22, 2011 Prepared by Alan Richardson
  64. 64. Chiller upgrade case study <ul><li>Efficient chillers </li></ul><ul><li>http://www.powerpax.com.au/casestudies </li></ul><ul><li>Upgrade to Powerpax chillers </li></ul>August 22, 2011 Prepared by Alan Richardson
  65. 65. References <ul><li>ABARES 2011, Energy Update 2011 , Accessed at < http://adl.brs.gov.au/data/warehouse/pe_abares99010610/EnergyUpdate_2011_REPORT.pdf >. </li></ul><ul><li>Department of Climate Change and Energy Efficiency 2010, Report of the Prime Minister ’s Task Group on Energy Efficiency, Accessed at < http://www.climatechange.gov.au/~/media/submissions/pm-taskforce/report-prime-minister-task-group-energy-efficiency.pdf >. </li></ul><ul><li>Langham, E., Dunstan, C., Walgenwitz, G., Denvir, P., Lederwasch, A., and Landler, J. 2010, Reduced Infrastructure Costs from Improving Building Energy Efficiency. Prepared for the Department of Climate Change and Energy Efficiency by the Institute for Sustainable Futures, University of Technology Sydney and Energetics. Accessed at < http://www.climatechange.gov.au/what-you-need-to-know/~/media/publications/buildings/building_our_savings-pdf.pdf >. </li></ul>August 22, 2011 Prepared by Alan Richardson

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