Here are some key things to consider.

Many homes still have a manual thermostat.

Same thing with the AC in the summer.

SmartThermostatSavings2

Forget to set it back or turn it up, and there are no savings.

The same can be said for programmable thermostats.

Ultimately, the whole disciplined-user model falls apart when observed under real-world conditions.

A Nest Learning Thermostat showing the peak-time energy saving feature.

Nest/Google

But those people are clearly in a minority.

Googleestimates users of its Nest Learning Thermostatsave 10-12% on heating and 15% on cooling costs.

Ecobee estimates that its userssave 26%on average.

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The ecobee SmartThermostat makes scheduling off-peak times and automatically adjusting your thermostat for comfort a breeze.

The ecobee SmartThermostat makes scheduling off-peak times and automatically adjusting your thermostat for comfort a breeze.

For example, it would be easy to overlook the Sunblock feature on theNest Learning Thermostat.