Solar space-heating system--Yosemite National Park, California

A 12 months performance of Visitors Center installation suffered from low insolation, high energy dissipation, and equipment breakdown. System has 980 square feet of liquid flat-plate collectors, water energy storage, 4-mode control, heat exchangers, pumps, and plumbing. Design expected system to supply over 50 percent of annual heating demand, but only 109 million Btu were conserved.