As much as the refrigerator, lighting, TVs, computers, and stereos combined. In fact, 10% of all U.S. energy is controlled by thermostats. That’s the equivalent of 1.7 billion barrels of oil per year. But in most homes the thermostat is an unassuming beige box. It doesn’t matter if it’s a manual or complicated programmable thermostat, we do with it what we’ve always done: get up, walk over to it, and change the temperature. Every few hours. Every day. 1,500 times a year. A lot, it turns out. The EPA says a properly programmed thermostat can cut 20% off your heating and cooling bill. But to program it right, we have to give the thermostat an exact schedule: lower the temperature at 8 AM, turn it up when we get home, lower it again when everyone’s in bed. The problem is, our lives don’t go according to schedule: we leave for the weekend, go out to dinner, stay up till 1 AM. Programming a thermostat right is almost impossible. According to one study, 90% of programmable thermostats are rarely or never programmed. The EPA even took away their Energy Star rating. So we started looking for an alternative. We still try to save energy, of course. We turn down the thermostat when we can, we don’t set it too high or low. But we’re human. We forget. Until we see our energy bills. You’ll spend $30,000 heating and cooling your home over the 20-year life of your system. In that time, the $249 Nest Learning Thermostat, which takes 30 minutes to install and programs itself in a week, can save you $6,000.We install hundreds of thermostats a year and have been closely monitoring the programmable thermostat market. The Nest is a clear winner. Only 10% of programmable thermostats are programmed to save energy, but thanks to learning, 99% of Nests have schedules that reflect their owner’s lives.Nest saves the most when you teach it well: just turn the heat down at night or turn off the AC when you leave the house. Energy saving features like Auto-Away™ and Energy History will become available as Nest learns.Auto-Away turns heating and cooling down automatically when no one is home, saving energy when you don’t need it. Energy History shows you how much energy you’ve used daily. By now, Nest has made a schedule for your home. One-off temperature changes won’t confuse it, but change the temperature a few days in a row and Nest will catch on and adjust its schedule. When you teach Nest well, you can save up to 20% on your heating or cooling bill. After an unseasonably cold day, you log in to your Nest Web app from the office to adjust the temperature at home. Control multiple thermostats easily and check how this cold snap has affected your energy use in Energy History.