Show Me The Numbers: Resources for Estimating and Comparing Energy Use

So, you’ve decided you’re ready to make changes to your house that will save energy. Maybe you’re deciding which energy efficiency investments will give you the best bang for your buck. Or maybe you have already installed a new heating system and want to see the data to backup the savings claims. There are a number of ways to measure energy use in your home, ranging from manual calculations to online software to in-home monitoring devices. Whether you want to determine the energy consumption of a particular appliance or determine how your house’s energy trends compare to others, here are some calculation resources that can help.

Break it Down: Energy Use for Specific Appliances

When you get your utility bill each month, it tells you how much total energy you consumed throughout your entire household. But how do you know if your coffee maker or your TV uses more energy? If you are trying to decide between purchasing a new refrigerator or a new washer/dryer, how do you know which will save you the most?

The Kill-A-Watt Meter is a hands-on tool that gives you immediate feedback about how much electricity a particular appliance uses. Just plug your TV, coffee maker, computer, and other electronics into the Kill-A-Watt, plug the Kill-A-Watt into the wall outlet, and then the screen will display the kilowatt-hour electric demand. It’s easy to use and understand, so you can get the whole family involved! The Alexandria Library has 18 Kill-A-Watt meters available to check out, or you can purchase your own for about $20. View this short video for more information.

The FAST-Track Analysis tool of the EnergyGuide Home Analyzer is a free, online application that allows you to enter information about your house and estimate the potential savings of energy-efficiency retrofits. For example, the Fridge Calculator asks you to enter the style, age, and size of your existing fridge to calculate what you will save by replacing your old refrigerator with an energy-efficient model. An In-Depth Analysis tool, providing “top to bottom analysis of your energy use” is also available, as well as a similar Calculator tool for small to mid-sized businesses.

If you’re interested in water conservation measures, check out the EPA Water Sense Calculator to compare the water and money savings associated with replacing showerheads, faucets, and toilets with lower-flow models.

Seeing the Big Picture: Whole House Analysis

The Home Energy Saver (HES) is an easy-to-use, free, online tool developed as a collaborative effort of Department of Energy, Environmental Protection Agency, and Lawrence Berkley Laboratory (among others). After you enter a series of building design, appliance, and utility information, HES makes customized recommendations for energy-saving upgrades that are appropriate to your home and make sense for the home's climate and local energy prices. HES generates a profile for the home’s existing energy profile compared to that with the recommended package of energy saving upgrades.  HES also estimates the home's carbon footprint and shows how much it can be reduced. Join the over 6 million people who have visited the site!

Earth Aid is a unique analysis program that allows you to automatically track trends in your utility bills – while earning prizes (such as coupons or gift certificates) for saving energy. Based on your location and utility information, EarthAid also provides a list of incentives available to residents for energy efficiency improvements. For more information, see the “Sweet Rewards for Saving on Your Utilities”.

Keep Up with the Joneses: Compare Your Home’s Energy Performance

How does your home energy performance to compare with similar homes in your area? If you have five minutes and your last 12 months of utility bills, use the Energy Star Home Energy Yardstick find out. In addition, the Yardstick directs to resources for energy-saving home improvements from Energy Star that can help you improve your score.

More than the Money: Carbon Calculators

If you are interested in understanding your home’s impact on global carbon emissions, check out the EPA Emission Calculator. The EPA’s Calculator helps you to: (1) estimate your current total household emissions, (2) explore actions you can take to reduce your greenhouse gas emissions, energy use, and waste disposal costs, and (3) see how much you can save (in dollars and emissions) by taking the recommended actions.

The Nature Conservancy also offers a free online Carbon Footprint Calculator that considers home energy, driving and flying, food and diet, and recycling and waste for a whole-lifestyle carbon footprint analysis.

No matter what you are trying to measure, there are a variety of no-cost or low-cost tools available to analyze your home and guide you in making smart, energy-and-water efficient improvements to your home.