#11 SunPower. SunTile roof tiles and solar panels provide a built-in look. The tile product suits S-shape and flat tile profiles; each panel measures 17 by 59 inches and achieves an STC power rating of 63 W. Panel-designed products integrate with various roof finishes, measuring 61.39 by 31.42 inches and achieving an STC maximum power rating of 210 W and a conversion efficiency of 16.9% per panel. The company’s solar cell technology delivers up to 50% more power than conventional cells and converts up to 22% of available sunlight into electricity. 877.787.6527. www.sunpowercorp.com.

#12 Akeena Solar. Andalay solar panels are all-black and feature built-in racking and built-in wiring for a smooth, flush appearance that resembles skylights. With 70% fewer parts and 25% fewer attachment points, the panels for a small house can be installed in less than an hour, the company says. These features also mean fewer penetrations in the roof and less opportunity for leaks and failure. 408.395.7774. www.andalay.net.

#13 Solatube. The Solar Star Conversion Kit boosts performance and lowers noise of existing attic fans. The Solar Star ventilator is powered by a 10-watt photovoltaic solar panel and features a high-performance brushless motor and five-wing injection-molded fan. The unit works continually to maintain low humidity and temperature levels, eliminate wintertime condensation, and keep attic heat from building up in the summer. It requires no electrical hookup. 888.765.2882. www.solatube.com.

#15 Evergreen Solar. ES-Series poly-crystalline solar panels feature String Ribbon wafer technology. The panel’s design consists of 108 polycrystalline silicon solar cells, anti-reflective tempered solar glass, EVA encapsulant, polymer backskin, and a double-walled anodized aluminum frame. Each panel measures 37.5 by 61.8 inches and weighs 40.1 pounds. Three panel options achieve an STC maximum power rating of 180 to 195 W. 508.357.2221. www.evergreensolar.com.

#16 GE. Available in indoor or outdoor models, these tankless gas water heaters measure 23 inches high, 14 inches wide, and 10 inches deep, making them ideal for small spaces, such as attics and closets. Users can choose from two flow rates: a natural-gas 7.5-gpm model or a 9.4-gpm unit available in natural gas or LP gas. By heating water only when needed, the tankless units maintain efficiency ratings of 0.82, compared with 0.53 to 0.62 for standard water heaters, and can save homeowners up to 25% on water-heating costs annually, the manufacturer says. 800.626.2000. www.ge.com.