I am not sure if I blogged about it or not but I recently gutted all of the insulation and framing out of my unfinished basement. You see, I had found some mold. The result is one heck of a cold basement which lead me to do some reading on the subject.
I have read that you can up to 20%-30% of you heating bill just by adding proper insulation. I am proof that since I took the insulation out of my basement that it is way colder down here. I haven't been cranking the heat but instead wearing extra clothes and keeping extra blankets handy.
Depending on the size of your basement it's probably going to cost a few hundred dollars or more but you can expect to get that back over a two or three year period in heating savings. It's also a project that for the most part you can do yourself if you have a guide on how do to do it. You can read the source article as it is excellent in covering some of the different kinds of insulation that you can use in your basement and goes over everything from top to bottom.
You are 100% correct, insulation is the fastest most effective method of reducing your energy costs. This is why the Australian government has actually just announced free rebates of up to $1600 to homeowners and landlords to insulate their homes for free. This in addition to solar panel and solar hot water rebates makes the future look bright for the adherence to the carbon footprint reduction commitments offered by the government by 2012
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