Ordinance trends toward energy accountability
Legislation in San Francisco is leading the reform of nonresidential building energy efficiency by placing focus on the need to continuously evaluate and act on changing energy uses in buildings.
Energy efficiency is a measurement that is constantly being updated by new technologies, but the passage of a San Francisco Energy Performance Ordinance may drive a building standard that changes the way buildings are maintained. The city and county of San Francisco board of supervisors passed, in early February, the Existing Commercial Buildings Energy Performance Ordinance (PDF). The ordinance requires nonresidential building owners to account for their energy efficiency via frequent audits and benchmarking. For now, the push for benchmarking and auditing is exclusive to a few areas of the United States (like San Francisco and New York), but some consulting engineers said it could become more universal.
Cole Roberts, senior consultant at Arup, San Francisco, said, “If we look to the recent developments in green building codes and standards, it certainly suggests we’ll see broader codification moves. But that won’t necessarily mean more clarity. Codification has added value. It has also added complexity.” The clarity of these indicatives cannot be decided until there is a universal acceptance of such mandatory, national legislation.
Michael Bove’, PE, principal at Affiliated Engineers Inc. (AEI), Walnut Creek, Calif., said, “Whether it becomes part of such codes is not as important as the move by cities, owners, and engineers to adopt good, sustainable, energy-efficient, and measurable building design and operational practices.”
In San Francisco, nonresidential buildings will be required to complete auditing, benchmarking, and reporting of findings, no less than every five years. The ordinance splits commercial buildings into two classes, depending upon square footage. Buildings with gross areas of 10,000 to 49,999 sq ft will be expected to follow through a Level I audit, which consists of a brief on-site survey that identifies and provides low- and no-cost energy saving measures, as well as lists potential capital improvements. Large buildings will follow a Level II audit, which features a detailed on-site survey and energy analysis that identifies and provides savings and costs analysis of all practical measures. All audits must meet their respective levels within Procedures for Commercial Building Energy Audits, published by the ASHRAE. Benchmarking will be unified via the Energy Star Portfolio Manager, a free, online benchmarking tool provided by the U.S. Environmental Protection Agency.
New York has similar legislation, Int. No. 476-A and No. 973-A, that entails similar benchmarking, energy auditing, and retro-commissioning measures for private/existing buildings greater than 50,000 sq ft, and public buildings greater than 10,000 sq ft.
Bill Talbert, PE, LEED AP, senior sustainable analyst at Affiliated Engineers Inc. (AEI), Madison, Wis., said, “This ordinance is similar to things in the industry, like a meter requirement on the new ASHRAE 189.1 Standard or LEED.” The ASHRAE 189.1 Standard applies to the same buildings as the existing 90.1 Standard, but dials in on energy efficiency more. “The ASHRAE 189.1 Standard doesn’t require an energy audit but does provide data for operators to monitor building and energy use,” Talbert said. The U.S. Dept. of Energy made a preliminary estimate of weight average site energy savings for Standard 189.1 of 27% over Standard 90.1.
U.S. Green Building Council LEED certification is a field that constantly sees changes and updates with a required update every three years. LEED for Existing Buildings heavily features Energy and Atmosphere (35 of the total 110 points), with up to 18 points coming from high Energy Star ratings and up to 3 from Performance Measurement. The San Francisco Ordinance uses the Energy Star Portfolio Manager, which may help incentivize LEED and building greener in general.
Bove’ said, “Many other regulations, design practices, industry standards and public ordinances such as this drive our engineering solutions above and beyond building code [International Building Code (IBC) , National Electrical Code (NEC), and Uniform Mechanical Code (UMC)] requirements.”
San Francisco has taken large strides in green building and energy efficiency, but this ordinance may prove to be the most feasible to apply nationally. Building auditing, benchmarking, and reporting are not just good for owners; by making energy efficiency more transparent, consumers can make more educated purchases in terms of rentals. Building owners and property managers across the United States have been using benchmarking to save energy and money, and also to attract tenants. Studies show that energy-efficient buildings command higher rents, sell for more money, and have lower vacancy rates than other buildings.
The DOE said on its Building Energy Codes page: “Buildings use 39% of our total energy, two-thirds of our electricity, and one-eighth of our water.” The National Renewable Energy Laboratory (NREL), in conjunction with the DOE, has released two technical reports providing recommendations on 50% energy savings for larger office buildings and hospitals with current technology. A majority of building owners has little idea of how effective their energy systems are and consumers have few ways of comparing buildings to make informed decisions. The difficulty lies within pushing the idea of energy benchmarking over the hurdle of cost.
“Regular commissioning/energy auditing will point out where things are failing, but at the same time it’s not free – so there needs to be a clear incentive for a majority of those affected,” said Talbert. If the San Francisco ordinance provides low- and no-cost energy saving measures, as it says it does – at least for Level I buildings – then it can feasibly be implemented nationally.