I still use regular alkalines for my remotes, but that’s about it.

A word of caution on buying regular alkaline batteries, THE ONLY brands I’m aware of that will replace/repair your device if the battery leaks are Rayovac, Energizer and Duracell. Beware the store-brand alkalines because of this. Rayovacs tend to be the least expensive of the 3 at WalMart.

I once had an expensive Nikon camera replaced by Rayovac because of battery leakage.

Crude attempt to follow:

Assuming a 2Ah capacity on a typical AA battery at 1.5 volts, you are also buying 3Wh of energy when you buy a non-rechargeable battery. At 30 cents per kilowatt hour, this comes to about a tenth of a cent if your battery is displacing mains electricity. Not a lot – 3 cents of the price of a 30 pack.

However, you’re not making a choice between putting in a battery and plugging a device into the wall – you want charged batteries. So we can’t ignore the inefficiency in the charging process caused both by loss in the charger and by the internal chemistry of the battery which will always be converting a chunk of the incoming current into heat. Unfortunately, I haven’t been easily able to find figures on that (might be an interesting experiment with your charger and a Kill-A-Watt or the like), but it might well be a pretty steep drop-off.

I’d be very interested in an analysis with better numbers.

One of the best tips I’ve heard is to remove your batteries from any device that you don’t use constantly. Apparently they drain more quickly when left in an unused device. That may not be a great idea for items you need often (wireless mice, remote controls) but for things like RC toys, it’s a good idea in my opinion.

Also, people need to ALWAYS recycle ALL batteries when they finally die. The metals and elements in them keep manufacturers from having to dig that stuff out of the ground and help lower prices as a result.