The document discusses the performance of green, sustainable buildings and whether they deliver on their promises of reduced energy and water usage. It notes that while green building is growing rapidly, some certified green buildings are underperforming and not achieving the expected energy savings. The document advocates for improved performance measurement and reporting to help ensure that green buildings actually perform as intended from an environmental perspective.
Green building vital in global carbon pictureGreen building growing rapidly in all sectorsGreen building business case is provenBUT, many green buildings are not performing as predictedBuilding energy & water performance reports vitally neededBuildings must eventually measuretotal carbon performanceZero-net-energy buildings feasible today
By reducing energy and water use as well as transportation energy use
More than 2 billion sq.ft. certified projects, more than 7 billion sq.ft. registered (maybe as much as 9 million sqft), as of September 1st.
14% reduction in CO2, 2025 vs. 2005NPV of green building: $650 billion in U.S.5x to 10x cost premium2020 Prediction: Green buildings 95% of new constructionGreen retrofits are 75% of all retrofits
If building energy use is this important to our collective future, why not know what’s going on?
“What gets measured, gets managed”Without reports, we are flying blind/can’t fixWhy should governments put their faith in green building without performance reports?
Here’s the problem: quite a few green building projects are not meeting their projections.
The first major study of LEED projects gave this result.
Issue: Average savings is 35% vs. standard (Kats)BUT, about 25% actually underperformOne LEED Platinum building:Modeled at 61% savingsPerforms at 48% savingsUnderperforming buildings hurt validity of green building premise
EU Energy Performance in Buildings Directive: in force since 2010; here’s a UK example.
Importance of embodied energy; forms a barrier to further carbon reductions
Where SHOULD WE be aiming? I decided to find out!LEED Platinum (or equivalent)Built since 2003>50,000 sq.ft. (>5,000 sqm)Non-residential useMust provide energy data for one yearWater data, as available
European stretch goal: 100 kWh/sqm/a PRIMARY energy useEuropean site use median: 135 kWh/sq.m.; 43,000 EUIU.S. Average: 400 kWh/m2/a (2003)50% better than average still not good enough!75% (or more) required2030 Challenge (next slide)Solon: 34,000 Btu/sq.ft./year energy use
2030 Challenge:DOE Annual Energy Outlook; Business As UsualAEO (expanded codes)AEO (best available technology)
Here is a chart of actual performance of 15/19 buildings (no labs/hospitals)Median use = 139 kWh/sq.m. (EUI = 44,000)
2000 workers in bldg.; 700,000 sq.ft.Difficult climate:-35C to +35C (-31F – 95F)22-story solar chimney Passive solar designUrban regenerationGreen roofsPassive moisture control111 kWh/sqm/year;35,000 Btu/sq.ft./yr
Zero Net Energy Buildings are Feasible today; here’s an example:35,000 Btu/sq.ft./year (measured 2011)
800 workers in bldg.; 360,000 sq.ft.Design/build; $254/sq.ft.Cold, dry climate - Passive solar design1600-kW Solar PVLabyrinth thermal massDaylighting designControl plug loads111 kWh/sqm/year;35,000 Btu/sq.ft./yr
Integrated Design Process Critical to SuccessStarted with the Procurement ProcessSet BSAGs – Big, Scary, Audacious Goals
200,000-sq.ft., commercial officeVedic architectural designLEED-CS/CILong axis north/south, to maximize morning sunHVAC: Enthalpy wheel, frictionless chillerSpace H/C only 13% 41% less water use182 kWh/sq.m./year;58,000 Btu/sq.ft./yr
56,000 sq.ft. academic building; narrow floorplateCold winters, humid summers100-KW BIPV system; 16% of annual electricity4 solar DHW collectorsGeothermal wells; four at 400’ deepRainwater harvesting91 kWh/sq.m./year; 29,000 Btu/sq.ft./yr
Double LEED Platinum, CS/CIFour stories commercial office, with17 stories rental apartmentsUnderfloor air w/chilled beamsDesigned to meet 2030 Challenge targets for 20104 turbines produce 1% of demandSolar water heaters provide 24%Operable windowsHarvested rainwater; 6500 sq.ft. green roofEnergy: 138 kWh/sq.m./year; 44,000 Btu/sq.ft.
Here is a chart of actual performance of 15 buildings (no labs/hospitals)Median use = 135 kWh/sq.m. (EUI = 43,000)
75,000 sq.ft.98 kwh/sq.m.Waste heat recyclingNatural ventilation using atrium exhaustHeat recovery from computer serversWater-only (no chiller) cooling via trickle vents and heat exchangers
74 kWh/sqm/yearLake water heating/coolingDouble skin façadeNatural ventilation500 employees, 210,000 sq.ft.
92,000 sq.ft., 200677 kWp solar PV, 538 sq.ft. vacuum tube solar thermalPrimary/source energy demand: 103 kWh/sqm (with 23 kWh/sqm solar) with embodied energyAtrium buffer zoneActive louvers for shading
Dutch Energy Rating: A+++GreenCalc score: 1,005185,000 sq.ft.100% sustainable energy on siteEnergy positive buildingBio-diesel 300kW CHP plantOffice: 114 kWh/sq.m./year
Here is a chart of actual performance of 15 buildings (no labs/hospitals)Median use = 151 kWh/sq.m. (EUI = 44,000)
50,000 sq.ft. renovationOn the equatorFocus on daylighting without heat gain41 kWh/sq.m. building energy use45 kWh/sq.m. Solar production
77,000 sq.ft.98 kWh/sq.m.6-Star Green Star Office Design5-star NABERSAlmost $3/sq.ft. annual energy cost savingsAutomatic louvers on west façadeActive chilled beamsComprehensive staff/facilities training
National Cheng Kung University52,000 sq.ft.40 kWh/sq.m./year energy useForest land permanently set aside for meeting zero carbon goal
Every building should be beautifulEvery building LEED PlatinumEvery building should aim at “BSAGs”Achieve measured 35 to 45 kBtu/sq.ft. (EUI) performanceDon’t settle for less!BE WILLING to SAY: If it doesn’t perform, it’s not a green building!
2030 Challenge:DOE Annual Energy Outlook; Business As UsualAEO (expanded codes)AEO (best available technology)
420,000 sq.ft. building89 kWh/sq.m. electricity use100 kWh/sq.m. total carbonBest tall building in Europe 2011
This one progresses with clicks
ARE YOU WILLING to SAY: If it doesn’t perform, it’s not a green building?