Twelfth story in an occasional series on the greening of New York City.
NEW YORK -- A technology once considered an exotic flourish for fancy new "green building" projects is quickly finding a home in Manhattan's older office towers.
"Thermal energy storage" ties big barrels filled with ice into air conditioning systems to help cool air.
Nicknamed "ice," the technology allows buildings to slash electricity use during long, hot summers.
Ice tanks help chill the Bank of America Tower, a new landmark near Bryant Park that has earned the highest certification rating from the U.S. Green Building Council (USGBC). The New York Times' new building also features ice, as does almost every major green building project here.
The tanks are not cheap, but they offer dramatic energy savings for building owners who are switching out aging heating, ventilation and air conditioning (HVAC) systems. That is why Jeff Meaney, senior vice president at financial adviser TIAA-CREF, installed an "IceBank" system built by CALMAC Manufacturing Corp. in his company's office tower.
When one of its chiller units failed a few years ago, TIAA-CREF called Trane, an HVAC equipment maker, whose consultants advised the firm to install ice-cooled equipment they said would pay for itself in energy savings in a few years.
"They delivered more than they promised," Meaney said.
Last week, executives from Trane and its corporate parent, Ingersoll Rand, hosted 300 building owners and market analysts on a tour of a few new ice systems. Rather than focus on New York's fancier green buildings, the tour focused on buildings that are not famous for having LEED certification, the USGBC seal of approval that stands for Leadership in Energy and Environmental Design.
The TIAA-CREF building features 30 tanks -- each 11 feet tall -- that insulate ice. Nearby, owners of the AXA-Equitable building on Seventh Avenue found room in the basement for 45 such tanks to help chill air circulating in the 1.8-million-square-foot complex. The CALMAC units are also in Rockefeller Center and have become popular with the Wall Street crowd, factoring into new heating and cooling systems in properties owned by Goldman Sachs, Morgan Stanley and Credit Suisse.
Meaney estimates that his building's system, the only rooftop installation that Trane has put up in the city, cost a little more than $3 million, but he said the company has already recovered that initial outlay.
Trane told him to expect energy cost savings of about $650,000 per year, but he said the company has reduced expenses in the range of $750,000 to $800,000 a year.
The ice system appears to be well-suited to New York's energy market, the system's manufacturers and distributors say.
Mark MacCracken, CEO of CALMAC Manufacturing Corp., said New York commercial buildings pay about 75 percent less on average for electricity they consume at night.
"It's clearly better to do thermal at the building," MacCracken said. He added that the systems his firm makes are on average 30 percent more energy efficient than many of the steam-based units now common in the city.
His company's IceBank system takes advantage of differential electricity pricing in New York by making the ice at night, using power only while it is cheapest and while most other activity in the building has been shut down. In the daytime, as temperatures rise, the system uses ice to help supplement the energy normally used to cool air.
During a demonstration of the technology, Trane engineers said that even on the hottest of New York days, the ice takes care of about 50 percent of the cooling, while the building relies on the grid for the rest. On more average summer days, they estimate that ratio to be closer to 60-40.
The energy savings vary depending on the size of a building and how many units can fit in it; officials admit that finding space for the giant ice tanks is their biggest problem.
Trane and Ingersoll Rand hope to net more business from last week's tours and discussion, but officials there and at CALMAC say they already have a healthy number of back orders.
Next up is a massive project slated for 55 Water St., a Lower Manhattan property with an estimated 3.8 million square feet of space.
The systems' cost and complexity can make them a hard sell to some building owners. The systems include not only ice tanks but an elaborate array of pipes and vents connecting the ice storage with energy efficient electric chillers, all managed in a liquid crystal display via custom software.
But new city rules on energy efficiency are pushing property owners to consider air conditioning upgrades.
This year, new codes for existing buildings kick in that require energy consumption benchmarking and regular monitoring and enhancements.
And USGBC is introducing new standards for existing buildings seeking certification that require constant performance monitoring, aimed at ensuring that building owners don't skimp on maintenance and see their energy efficient equipment become less so as the years roll by.
Constant monitoring is needed for "overcoming the very, very common 'run to fail' strategy," said Deane Evans, director of the Center for Building Knowledge at the New Jersey Institute of Technology.
Financing retrofits to ice thermal storage is still a challenge. Most projects sold to buildings are paid for directly from the buildings' owners. But government and the green building industry are coming up with ways to help owners tap financing, through energy efficiency grants and a "property-assessed clean energy" financing arrangement for commercial properties that Greg Hale at the Natural Resources Defense Council said should become a reality by next year.
Meanwhile, CALMAC's MacCracken, who leads the U.S. Green Building Council's board of directors, said the LEED program is increasingly becoming dominated by existing buildings, whereas earlier, the Gold, Silver and Platinum certifications were mostly pursued by new construction.
Aside from the new monitoring standards, he said the council will soon be introducing an "international LEED" certification scheme under which buildings overseas can undertake retrofits and earn a seal of approval, based on "alternative compliance paths."
New York's real estate community is also beginning to pay attention to the proliferation of ice tank air conditioning systems and other eco-friendly enhancements.
Space in the newer LEED-certified buildings already rents for a premium, but Karen Penafiel, a vice president at the Building Owners and Managers Association, said older properties could also become more profitable if they are installed with the type of ice-based HVAC equipment now spreading in Manhattan.
"Tenants are now demanding high-performance buildings, and they're willing to pay for it," she said.
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