Designed for cost-effective growing, the energy-efficient Solar Light Clearspan Truss greenhouse has a high-pitched roof that provides excellent air circulation and maximizes winter sunlight, leaving ample room for energy curtain systems, lighting, heating, vent equipment and transportation systems. The Solar Lights rack and pinion roof and side vents provide natural ventilation, and other energy saver options include energy curtains, ebb and flow benches, motor Á managers and material handling products. Environmental equipment runs only when necessary. Agra Tech. (925) 432-3399.