By Mike Dunn

PHILADELPHIA (CBS) — Owners of commercial properties in Philadelphia have until the close of business today to tell the city how much energy they’re using. Those who don’t could eventually faces fines.

It’s a new law in Philadelphia: commercial building owners must now use an EPA web site to calculate their energy usage, then report that figure annually to the city.

Overseeing the program is Alex Dews of the Mayor’s Office of Sustainability.

“We’re seeing churches, schools, skyscrapers — all types of buildings that are measuring their energy use so that they can better manage building performance,” he told KYW Newsradio this morning.

The benchmarking includes a building’s water and electrical usage in 2012, its size, use, number of employees, and hours of operation.

The reporting deadline was originally the end of October, but the city extended it because that month’s federal government shutdown also shut down the EPA’s web site.

“Quite a few (building owners) that we spoke to were in process of benchmarking and were not able to access their account during that time,” Dews says.

So far about half the city’s building owners have complied, accounting for about two-thirds of the 320 million square feet of nonresidential property in Philadelphia.

Those who miss the deadline will get a warning and a thirty-day grace period.

“If building owners haven’t complied, they’ll receive a warning notice of violation. At that point they’ll have an additional thirty days to comply with the law, and after that would be assessed the violation,” Dews says.

Those violations begin with a $300 fine but could escalate.  Dews says that aside from avoiding the fines, the benchmarking also has a positive benefit: building managers can get hooked up with city and utility resources to plan improvements to their properties.

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