The Solar Attic Fan is a simple and environmentally sensible solution that can save you money. Powered completely by free solar energy, this sleek and efficient vent is both compact and quiet. Fully operational right from the box, it installs easily, with no electrical wiring, no expensive electrician and city permits. And let's not forget powerful! A single 30 watt unit can fully vent up to 2,500 square feet, operating at up to 1,550 cfms. Place it wherever you need improved circulation; attics, lofts, workshops, storage sheds, garages, even barns. Attic venting is an important aspect in maintaining a healthy energy efficient home. Proper venting cools your roof extending the material life and reduces the load on your air conditioning system. Attic venting also increases fresh air circulation which reduces vapor build up generated by every day activities like showering and cooking. Excess moisture trapped in your attic can cause a variety of problems from rust and rot to increased bacteria and mold counts which can have a direct impact on your respiratory health! Passive vents have been a part of building codes for years. Soffit vents, ridge vents and louvers rely on nature to provide sufficient air pressure and air movement. So the majority of the time your attic is stagnant and continues to build up heat and moisture. The 30-watt Natural Light Solar Attic Fan exhausts up to 1,550 CFM, and up to 2,500 square feet of attic space. No wiring needed. Lower your electricity consuption using this high quality solar powered attic exhaust fan today! Note: If you live in a climate that regularly goes below 70 degrees Fahrenheit during any part of the year, (most of the US) you'll also want a thermostat switch, purchased separately here.