From an article in Sustainable Times:

After reviewing several proposals, Focus on Energy selected two locations for showcasing this particular solar energy application.

One of the Focus on Energy-funded demonstration sites is the Cooperative Educational Service Agency, located in Chippewa Falls.

Better known as CESA 10, this agency provides energy management services to 30 school districts in northwest Wisconsin. A low-rise building with plenty of unshaded roof space, the CESA 10 office presents an ideal setting to test a solar application that could very well be a good technology fi t for the schools served by this agency.

“We hope this installation will enable us to practice what we preach,” said Todd Wanous, an energy manager at CESA 10 and the driving force behind this demonstration. Placed in service in August 2009, CESA 10’s innovative installation features Wisconsin’s first example of a modular rooftop air heating system called SolarDuct®.

On the roof are three banks of corrugated collector panels, each connected to the building’s air handling system. The dark-colored panels are covered with ventilation holes that draw in outside air. Sunlight striking the panels warms the air passing through the holes. Through the ducts running behind the arrays, ventilation fans draw the preheated air into the building’s air handling system.

CESA 10’s SolarDuct® unit is designed to supplement, not replace, the natural gas furnaces that used to be the sole source of space heat.

However, this system does not necessitate additional fans or blowers to move the preheated air throughout the building. As a result, there is no parasitic energy loss to factor in.