Improving the energy efficiency of your home is a great way to save money, and the savings increase each year as utility costs continue to rise.
But homeowners can encounter lots of confusing information about which improvements make the most sense, and some of the claims about energy savings are downright misleading.
Here are some tips on sorting through the hype.
The best place to start is by having a good idea of where your energy dollars are going.
See if your utility company offers a free online energy audit, many now do, that can help you understand whether you are using more energy than people with similar-size homes and how that power is being used.
Depending on how detailed you want to get, Charleston County libraries let you check out an energy monitor, which can tell you how much power is used by anything you can plug in to the device.
In most cases, I find that the results of a federal study on energy use in a typical single-family home is all you really need to evaluate claims about savings.
That study said the typical home has annual energy costs of $2,200, and that 46 percent of the energy is used for heating and cooling.
So if your house has similar energy use and you see a claim that you can cut your energy bill in half by replacing your heating and cooling system, you know that claim can't be true. If you stopped heating and cooling your home entirely, you wouldn't reduce your home's energy use by 50 percent.
I'm not suggesting that people shouldn't spend the money for an efficient HVAC system when it's time to buy or replace one. When one of my heat pumps looked ready to die several years ago, I replaced it with a very efficient unit. The equipment upgrade was one step among several that helped reduce my home's electricity demand by about 20 percent.
The important thing is to be realistic about expectations.
Energy Star, a joint program of the U.S. Environmental Protection Agency and the U.S. Department of Energy, estimates that replacing an old HVAC system with one that meets Energy Star guidelines can save "up to" 20 percent on heating and cooling costs, which would be up to 10 percent of your total energy bill.
The same sort of calculation goes for energy-efficient windows. Leaky windows make your home less comfortable and waste energy, and if they need to be replaced, it makes sense to consider energy-efficient replacements. But don't expect a big bang for your buck in terms of savings.
Let's say 10 percent of your heating and cooling costs are due to inefficient windows. That would be pretty bad, but it would still account for less than 5 percent of your total energy costs, or under $110 a year. So there are many reasons to replace old windows, but don't expect them to pay for themselves quickly with energy savings.
Government and nonprofit groups involved in energy efficiency work agree that the best return on your energy-efficiency investments will come from improving insulation, sealing leaky ducts, installing programmable thermostats, and replacing inefficient incandescent light bulbs.
Additional gains in energy efficiency and savings on power bills come from simple lifestyle adjustments and routine maintenance. Wash most clothes in cold water, set the water heater at 120 degrees and adjust window curtains and shades to let the sun help warm your home in the winter.
Replace HVAC filters regularly because dirty filters make the system work harder, keep the refrigerator coils clean, and repair leaky faucets and toilets that waste water and run up your bills.
Grab that low-hanging fruit first before considering expensive equipment upgrades.