Mechanical engineering professor Keith Sharp, several Speed School students and a crew from A Green Building Group out of Richmond, Ky., began construction of the 12-foot x 24-foot passive solar test building south of Ernst Hall last week.

Passive solar design uses windows, walls and floors to reject solar heat in the summer and to collect, store and distribute solar energy in the form of heat in the winter.

Walls in the small structure are 12-inches thick and have an insulation rating of R-50. Its 16-inch-thick roof has a rating of R-70, Sharp said.

Sharp and his Renewable Energy Applications Laboratory will use one of the two rooms as a control; they will test a modification to the building’s passive solar design in the other room. The team expects the modification to increase energy efficiency by 15 percent, he said.

With “at least a year’s worth” of solar energy experiments planned, Sharp said he is looking for other researchers who might make use of the facility, too.

The building is funded by a grant from the Department of Energy.