SolarWall was invented by Conserval Engineering's president, John Hollick in the late 1980s. Conserval decided to focus on building integrated solar heating with its SolarWall invention often referred to as transpired collector. SolarWall systems are building integrated perforated metal heating panels mounted onto sun facing walls of buildings to heat and ventilate large buildings with a requirement for ventilation air or fresh air.
Traditional solar thermal panels were designed to heat domestic hot water and were generally roof mounted. Space heating accounts for the largest energy usage for buildings in cold climates especially where snow accumulation is common. It was decided to have a solar collector that would not freeze, thus air became the heat transfer medium instead of water or antifreeze; a wall mount orientation was selected to eliminate any snow buildup associated with roof mounted panels and the vertical orientation was found to increase winter solar gain as it was more perpendicular to the low winter sun angle and the snow on the ground was found to reflect in as much as 50% more solar energy. An additional bonus with utilizing the wall and a building integrated design has been much lower costs.
Building integration of a solar energy system such as SolarWall, became popular with architects incorporating LEED certification, a popular green building design standard developed by the U.S. Green Building Council into their Clients' building designs.
Building integrated solar air heating has become a popular form of solar heating, with thousands of installations in over forty countries. According to Solar Energy Industries Association over 5,000,000 square feet of these panels are in operation as of 2015.
The Conserval Group of Companies include Conserval Engineering of Toronto, Conserval Systems of Buffalo New York and SolarWall Europe of Paris. SolarWall is marketed through licensees and distributors around the world.
The SolarWall PV/Thermal technology developed by Hollick of Conserval Engineering is a hybrid solar system that generates both heat and electricity from the same surface area. By combining PV with the air heating technology, the PV heat is removed from the back and drawn into the transpired collector, thereby cooling the PV modules. The heat energy is then ducted into a building’s mechanical ventilation system or to an air water heat exchanger where it offsets the conventional heating loads. The end result is that pairing the SolarWall heaters with PV maximizes the solar energy from a given space by allowing buildings to have both solar electricity and solar thermal energy.