Sam Roudman’s New Republic article about the Bank of America building in NYC has stimulated much discussion about how we look at energy efficiency of a building. The 2011 Energy Benchmarking data released by NYC showed that this Platinum LEED-certified building had one of the highest source energy intensities of all NYC office buildings – 363 kBtu/sf. NYC has just released 2012 benchmarking data which has this figure at 358 kBtu/sf for 2012. Detractors call it an energy guzzler — supporters say you cannot hold the USGBC or building owner (or building) responsible for the high energy demands of the trading floors run by the building occupants. I cannot add to this debate — it will continue.
But there is another important issue that needs to be addressed. The energy used by the Bank of America Tower is 20% higher than was predicted by its designers in 2010. At that time the designers claimed the source EUI would be 306 kBtu/sf. That figure, they said, was 14% lower than the baseline case. But actual source energy use is 20% higher than projected — even higher than the baseline case! Why were designers 20% off? Surely they must have been aware of the intended use of the building. The trading floors and their 5-monitor work stations could not have been a surprise.
Unfortunately this is common scenario — building energy projections that are significantly lower than measured consumption. The design teams always claim the building use was different than intended — they couldn’t anticipate the changes. It all sounds so hollow.
So long as LEED certification is based on such projections rather than actual consumption it will not produce the desired energy performance. The loop needs to be closed.