Monday, June 21, 2010

Reducing the Cost of Air Conditioning

The best ideas for protecting the environment are the ones that save money as well. It’s hard to get people to spend more money for the good of the environment, but it can be easy to get them to save some money if it’s painless.

Currently, the typical air conditioning system in most homes cools the entire house to a temperature set by a thermostat. In some cases, this chosen temperature varies throughout the day. However, this system is inefficient in two ways:

1. At night, most people set the thermostat lower for sleeping, but they really only need the bedrooms cooler, not the rest of the house. My air conditioner often works in the evening for several hours cooling the whole house down by two degrees. Some automated venting could concentrate the cool air in just the bedrooms to greatly reduce power consumption and save money.

2. Humidity is a big factor in the perception of temperature. But, thermostats only let users select a temperature. There are times when 26 degrees feels too cool and other times when 22 degrees feels too warm because of humidity differences. Another possible factor in the perception of inside temperature is the outside temperature. It seems foolish to sit in an air-conditioned house feeling cold sometimes because the thermostat can’t be set to match the way people perceive temperature. At a minimum, thermostats need to take into account humidity.

Solving these problems could cut down significantly on power usage and make us more comfortable in our homes at the same time. Automated venting would involve some cost, but adding a humidity sensor to thermostats can’t be too costly. Government support for solutions like this might get more support from homeowners than some current efforts to drive adoption of thermostats that allow the government to turn off your air conditioning remotely when they judge it necessary.


  1. But do you need Air Conditioning, or do you just want it?

    We both grew up with no A/C in our houses as kids, and seemed no worse for wear (that was for the rich kids). Why do we need it now?

    The reason is we are both willing to pay for our own comfort (at least one of the reasons). Interesting how A/C became the norm in a very short period of time.

  2. @Big Cajun Man: As long as it is affordable, people will use air conditioning whether they need it or just want it. However, if we can make air conditioning work better so that people are more comfortable and use less energy, then we have a big win.