Land and shelter Natural building Passive solar Biofuels Sustainable transportation Grid-tied photovoltaics Solar hot water systems Plus, over 150 pages of maps, wiring diagrams, formulae, charts, solar sizing worksheets, and much more.John Schaeffer is the president and founder of Real Goods, the oldest and largest catalog company devoted to the sale and service of renewable-energy products. Now merged with Gaiam, Real Goods has converted over sixty thousand homes to solar energy since 1978, when it sold the very first photovoltaic module in America. Real Goods hosts the annual SolFest at its Solar Living Center headquarters in Hopland, California.