Measuring Home Energy Use

One of the most important steps before installing home solar is figuring out how much energy your home uses, and how big your solar energy system needs to be to cover that usage. Taking a close look at how much energy your various devices consume can be an eye-opening and behavior-changing experience.

We’ll start by exploring the average annual costs from powering the most common home appliances. Then to dig deeper, we’ll compare three home energy consumption monitoring tools. Finally, we’ll see how much money you might save from installing one of those tools, and if it’s worth the investment.

Where Does My Energy Go?

Whether you’re using the US Department of Energy’s Appliance Energy Calculator or a tool like EnergyUseCalculator.com, you will get a general sense of how much energy goes to power your home. These tools use different assumptions about how long a device is used per day and how much energy it uses. I ended up using EnergyUseCalculator for this post because I found its default assumptions to be closer to my experience.

Below is the estimated annual cost of 18 common household appliances, based on the national average electricity rate of 12.58 cents per kilowatt-hour. Even though you pay for energy on a monthly basis, seeing annual costs will help determine if home energy monitoring services are a good investment for you.

Look at where your money is going and how small changes, such as switching out inefficient lightbulbs, can add up to big savings over time. Energy efficiency brings an added benefit for solar homeowners, too. By cutting out wasted energy wherever possible, you’re not only saving on your energy bill, but you can install a smaller solar system to cover your home energy needs.

How Do I Monitor My Home Energy Use?

Now that you know roughly what’s driving up your energy bill, you may want to find out more about your energy-use profile and manage it in real time. Here’s one do-it-yourself approach: buy a $20 Kill-A-Watt meter, which plugs in between any appliance and the outlet and reports how much energy is being used. If you’ve got a suspected energy hog at home, that is one way to track it down.

But going plug by plug is a time-intensive process. There are several systems on the market that promise to measure whole home energy and make it easy to get it under control. We’ll compare three platforms that each seems to have active user communities and fairly high user ratings on Amazon: The Energy Detective (TED), Neurio, and Curb. We’ll also look at a more affordable option in Chai Energy.

The first three solutions are all quite similar. In your main electrical panel, they connect a sensor that communicates with a central hub, allowing a smartphone app or your computer to read a graphical display of all your energy use information. It functions like a smart meter that’s controlled by you, not your utility.

Chai Energy, currently available in most of California and Baltimore, Maryland, connects directly to your personalized energy usage data made available through the Green Button initiative. Going this route, you don’t have to hard-wire any sensors to your electrical panel. By upgrading to Chai Pro, you can see a detailed breakdown of how much energy various appliances are using.

Neurio and Curb let you set targets for reducing energy use, and suggest ways to achieve your goal.

Source: Neurio

You can explore energy use history and get alerts if you leave home with the oven on. You can also estimate monthly usage and get alerts if you’re on track to go over-budget.

Importantly, these systems are all compatible with home solar energy systems. Each offers a way to track energy generated by your solar panels and how much you’re saving every day using solar energy.

Is Home Energy Monitoring a Good Investment?

Neurio products cost $180 or $250. TED’s residential products cost $200 or $300. Curb starts at $400 and offers a $700 double-version for large homes. Chai is a free app. For $49, you can upgrade to Chai Pro for more precise monitoring.

For solar homeowners, it’s important to note that Curb is solar-ready out of the box, while TED and Neurio each require an additional investment, $150 for TED’s solar add-on and $60 for Neurio’s. Since many solar energy systems include professional monitoring, it’s up to you to decide if it’s worth the investment for the solar packages.

If the cost of home energy monitoring sounds like a lot, consider two facts. Every home wastes at least some energy, and a lack of knowledge is the main thing keeping people from reducing their energy use. Ask anyone who’s driven a Toyota Prius or another car that gives you real-time feedback on your current fuel efficiency, and you’ll understand how quickly people are willing to change their behavior. These services put knowledge front and center.

The Energy Detective highlights 36 independent studies showing that TED users save an average of 12.6 percent [PDF] on their monthly electricity bill. If you pay $100 per month to your utility, TED will pay for itself in two to three years.

A 2009 review of TED in The New York Times details the immediate costs of everyday activities, including reheating a cup of tea in the microwave and cranking up a space heater to full blast. The author, Joe Hutsko, found his own behavior changing to the point where he turned his heater down to low and bundled up on clothing—and cut his winter heating bill by as much as one-third.

You can’t manage what you don’t measure. If you think your home energy consumption could go on a diet, one of these tools might be right for you.