I love that life provides endless lessons in personal finance.

The other night Ben and I were having a “discussion” about our air conditioner.  He was worried that leaving it on all day was wasting energy and increasing our electric bill.

My argument was that turning off the AC during the day would only cause the unit to have to work harder once it was turned back on and would therefore use even more energy.

So we were at a stalemate.  And per my usual, I went to the Internet to find some answers.

Turns out, Ben was right.  (I can just imagine the huge smile on his face when he reads that line.)

And it wasn’t even close.

Site after site, says that turning off your air conditioner during the day saves more energy (and thus more money).

Many sites suggest using a programmable thermostat that can regulate the temperature automatically while you’re away and have your home the right temperature when you get back. While that saves more energy than keeping it the same temperature, it’s still not as energy efficient as turning it off.

Don’t take my word for it. You can do the Google research yourself.  Here are my three favorite responses.

Of course, you may have to make some accommodations if you have pets in the house.

But the bottom line is, if you want to save money on your summer utility bills, turn off the air conditioner when you leave for extended periods of time.