As I mentioned a few weeks ago, fall is a great time to make energy improvements—not just because of the change in seasons, but because October is Energy Awareness Month. I'm sure you all spent the weekend celebrating and throwing energy-efficient parties, maybe with a nice CFL-shaped cake.

No? Okay, I didn't either.

But there's one thing you should consider doing, and come April it might give you cause to celebrate: make an energy-efficient improvement that will earn you a tax credit.

With all of the attention on the state appliance rebates (many states are still offering them—check if yours is!), you may have forgotten about the tax credits for energy efficiency and renewable energy. Please don't!

If you're planning on making any improvements, be sure to check whether they qualify for a credit. Improvements that qualify include biomass stoves; certain heating and cooling systems; insulation material; roofing; water heaters; and windows, doors, and skylights. All of these have specific requirements to qualify for the credit, so check carefully before you buy. (Seriously, check--read about how I almost bought the wrong door, if you need more convincing.)

And here's why you should check NOW: the tax credits for energy efficiency improvements expire at the end of this year. So any improvements you make must be "placed in service" by December 31, 2010. And if they're not… well, sorry. That's it. You're out of luck. No credit for you! (Sorry, Seinfeld flashback.)

If you're thinking about a geothermal heat pump, solar energy system, wind energy system, or fuel cell, you have more time: those credits are available through 2016.

Our tax credits page provides details on all of the credits available. So if you needed a reason to celebrate Energy Awareness Month, make it that big fat tax credit you could get, plus the added comfort and savings that would come along with your purchase.

And by the way, someone totally needs to make a CFL-shaped cake. If you make one, send us a photo! Virtual cake isn't as much fun as real cake, but we'll post it on the blog anyway. Mmm, cake.

Allison Casey is a senior communicator at DOE's National Renewable Energy Laboratory, which assists EERE in providing technical content for many of its Web sites.