Prototype of high-efficiency rooftop air conditioning unit designed at DOE national laboratories in conjunction with the Commercial Building Energy Alliances.

The U.S. government has released specifications for a highly-efficient rooftop air conditioning unit it believes could save the country a plethora of electricity, and commercial properties a considerable amount of money.

The U.S. Department of Energy (DOE) had announced its laboratories were working on such a rooftop air conditioning (RTU) in fall 2010. However, it became clear on Tuesday that the project was successful when the DOE announced it would be holding a Webinar on building high-efficiency RTUs to interested manufacturers on February 23 via its list of upcoming forums posted on the Building Technologies Program Web site.

"High-efficiency rooftop units, when built according to the criteria of the new specifications, are expected to reduce energy use by as much as 50 to 60 percent compared to the current ASHRAE 90.1-2010 standard, depending on location and facility type," the DOE said in a statement.

In the meantime, the DOE has released a summary (PDF) and fact sheet (PDF) roughly outlining the specifications for the ten-ton capacity air conditioning unit.

Manufacturers of RTUs might want to take notice as the DOE has all but lined up buyers for manufacturers willing to build these types of units. The design was developed in conjunction with the Commercial Building Energy Alliances (CBEAs), a group of U.S. companies with vast commercial real estate holdings that includes Target, Walmart, and Macy's.

"CBEA members are eager to start purchasing these units and are encouraging manufacturers to develop products to these specifications," the DOE said in a statement.

"To help achieve the best-in-class rooftop units requested by industry partners, DOE national laboratories, including Lawrence Berkeley National Laboratory, the National Renewable Energy Laboratory, the Pacific Northwest National Laboratory, and Oak Ridge National Lab, will provide technical assistance to manufacturers or developers who want to build the more efficient units. Interested manufacturers will receive assistance in designing, constructing, measuring, and testing the new air conditioner units produced to this specification," said the DOE.

In conjunction with the release, the DOE's Pacific Northwest National Laboratory (PNNL) has also launched a free online cost calculator. The Unitary Air Conditioner (UAC) estimator allows a company to compare different high-efficiency or standard commercial air conditioning units based on more than a dozen different specs for a given unit and its location.