Solar energy is useful in all sorts of ways, and not just for heating water or creating electricity, either. A team of scientists at the National Renewable Energy Lab (NREL) developed a “transpired air” solar collector for commercial and industrial building ventilation way back in the 1990’s. Now NREL has put that solar technology to work in a new Research Support Facility (RSF). The solar collector allows the building to bring in “free,” preheated air, allowing for greater energy efficiency in the winter months.
The transpired solar collector is, in essence, a dark-colored, perforated metal plate on the south side of a building that gets warmed by the rays of the sun. A fan added to the building’s existing ventilation system slowly draws warmed ventilation air into the building through the plate, and the solar energy absorbed by the dark plate is transferred to the air flowing through it. This process can efficiently preheat the air going into a building like the RSF by as much as 40 degrees F.
This is a simple technology that could prove important to commercial and industrial buildings in the U.S., which tend to either skimp on fresh air–which is bad for those who work within them–or pay exorbitant fees to heat ventilated air in the winter months. It’s estimated that 13 percent of all energy used in the U.S. goes to heating residential and commercial buildings. The NREL transpired solar collector design is an improvement on earlier, more expensive models which required glass rather than perforated metal.
Apparently those involved with its design and construction of the building got a chuckle out of the fact that the technology they needed had already been developed by NREL. “We knew we needed to create pre-warmed air for the RSF and we found a product and kind of had to chuckle when we realized this was going to be perfect — the technology was made by NREL,” said Philip Macey, RSF project manager for Haselden Construction, in a statement. “That’s one of those moments when you realized you are obviously going in the right direction when things line up like this.”