Carol Ott in Green Ideas on September 25, 2012
Over the summer, New York City released the results from the first year of Local Law 84 of 2009. That's the energy-benchmarking initiative begun as part of Mayor Michael Bloomberg's plan to reduce greenhouse gases. More than 6,000 multifamily buildings submitted data into an online tool called the Energy Star Portfolio Manager that was developed by the U.S. Environmental Protection Agency. Because most buildings of this size are professionally managed, energy consultants were hired to do the work.
The city developed four working grades to use until a national standard is created. Each grade represents a range of energy performance based on the Source Energy Utilization Index (SEUI) number.
So what does this mean, exactly? First, you have to understand the difference between the two types of energy utilization indexes (EUI). "The big difference between source and site energy is in electricity," explains Jeffrey Perlman, president of Bright Power. "At site, every kilowatt hour of electricity used has 3,412 BTUs of energy in it. To create that kilowatt of electricity, a power plant has to burn approximately 10,000 BTUs of energy. Every unit of electricity that you use at your building is basically multiplied by three when you start looking at source energy.
"The city is using the source number," continues Perlman, "because that's what Portfolio Manager uses. That makes some sense because the price of electricity is higher if you account for the fact that there's all this waste in the system from the generation of the electricity to the usage of it. Also, carbon impact is based on source energy, not on site energy."
But First, a Warning
Your grade is based on a bunch of numbers, but square footage is the key. If that number is wrong, so are all the calculations that derive from it.
One problem emerged during the first year of benchmarking. Even though the square footage number posted on the Department of Finance (DOF) website was the starting point to find out if a building had to comply with LL84, that number turned out to be misleading. The DOF square footage numbers, for the most part, don't include basement space unless the area produces income. Which means that if your building's basement is used for a boiler, storage, or mechanical equipment, it is likely that its square footage wasn't included in your benchmarking.
Handy Footage
It is important to see whether your benchmark provider submitted the right number to Portfolio Manager. How do you do that? Finding the square footage number on the DOF website takes a bit of clicking, and only works for co-op buildings and not condominiums (where each unit is its own separate tax lot).
Compare this figure with the one in Portfolio Manager. Then, notes Laurie Kerr, deputy director for energy efficiency at the Mayor's Office of Long-Term Planning and Sustainability: "You should compare those two numbers [the one on the DOF website and the one in Portfolio Manager], and if they are the same, you should go back to the benchmarking provider and say, 'Please correct this,' and make sure that all square footage is being counted." All the benchmarking calculations are based on square footage, so if your basement floor is left out, your numbers will be off.
And then ... your grade? For now, how your building fared is between you and whomever you can call to find out your SEUI score. The city intends to make the scores public in the fall of 2013.
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