What are the biggest electricity consumers in a typical home?

As a baseline, consider that typical homes in the United States consume on average 30–60 kilo-Watt-hours (kWh) of electricity per day (=900–1800 kWh per month) at a cost of $0.10-$0.20 per kWh. Those running on electric heat often double these numbers.

  • In homes with electric heat, the heater can dominate all other electric consumers. Heat pumps, while considerably more efficient (1/3 – 1/2 the consumption) than straight electric resistance heat (like an electric baseboard heater) still consume substantial amounts of electricity. Consider that a typical heat pump system uses 3kW – 6kW while running, daily consumption in cold days can easily be 30–60kWh or more. This is why home insulation and air-tightness is such an important way of conserving energy. Same is true if the home is heated with oil, gas or propane – home heating and cooling costs dominate all others, so a tight, well insulated home pays dividends year after year.
  • Electric water heater – consumption varies drastically depending on a family size and hot-water usage. But an average is about 400 kWh per month. A modern heat-pump water heater can cut this in half.
  • Refrigerator/freezer – older units were much less efficient than a modern, EnergyStar unit. A typical range is 40–80 kWh/month.
  • Lighting – with the advent of energy efficient LED lights, this has shifted considerably. A home that has the equivalent of ten, 100W bulbs running 12 hours/day uses 12kWh per day or 360kWh/month. If all those bulbs were replaced by 14W LED bulbs that put out the same amount of light, that would be reduced to 1.7kWh/day or 50kWh/month. Lighting is an area where every home can dramatically reduce consumption by replacing conventional bulbs with LED in high use locations like the kitchen and living rooms.
  • Air conditioner – central air conditioners and their blowers consume from 3–7 kilo-Watt-hours (kWh) per hour of operation.
  • Home electronics – computers, DVRs, TV, stereos all add to a home’s use and together add up to 200W-1000W/hour, every hour. Typical consumption is 4–10kWh/day or 120–300kWh/month.
  • Cooking – electric ranges and ovens consume 2kW–4kW while running and might be operated for an hour or two per day on average.

Other items that add considerably to electric bills but are less common:

  • Pool pumps – most are drastically oversized and run 12 hours a day. A typical pump uses 2500W, so that’s 30kWh/day or 900 kWh/month! Replacing that with a two-speed or variable speed pump can cut this by 75% – well worth the investment.
  • Spas/Hot tubs – outdoor hot tubs use about 6–15kWh/day, depending on usage, design and temperature, call it 10kWh on average. That’s 300kWh/month. Since many people don’t use their tubs during the winter, it pays to shut it down for the winter, saving about $50/month.
  • Ponds – ponds have become very popular in the suburbs but most people don’t realize how much they cost to run. Those waterfalls require larger pumps, consuming 500W–1000W while a basic pond filter pump might use 100W-250W. Consider an average of 500W for 24 hours is 12kWh per day or 360kWh/month.

It’s extremely educational to install a whole-house energy monitor or use an inexpensive plug-in energy monitor to see how much energy each of your devices consume. But watch out, once you do, you may turn into a true energy geek, like me 🙂

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GE GeoSpring Heat Pump Water Heater

GEH50DEEDSR _ GeoSpring™ hybrid electric water heater _ GE Appliances

Intro

In July 2014, I purchased this GE GeoSpring heat pump water heater to replace my existing all-electric water that had sprung a leak. Admittdely, it was an impulse buy because Lowes was having a sale on them – probably to get rid of unwanted inventory because these have horrible reviews!

So why did I buy it? Because it was only a few hundred dollars more than a conventional electric water heater and I’d been wanting to get an integrated HPWH after my previous add-on HPWH died after just a year. Plus, based on the negative reviews, I felt that the people having problems were using earlier versions of the heater. So I’m crossing my fingers and hoping that it has a long, happy life.

Almost everything written in this article applies to all heat-pump water heaters. I’ll put the GE specific notes at the end.

What is a heat-pump water heater?

You may not know it but your refrigerator and air conditioner are examples of heat pumps. Through a process of compression, condensation and evaporation, they move heat from one place to another. In your refrigerator, that humming you hear when it runs is the compressor. The inside of the fridge is cold because the “heat” in the fridge is moved to the outside of the insulated box and blown into your kitchen. An air conditioner works exactly the same way – it cools the air inside the house and expels the heat outside.

The HPWH does the same thing except it uses the heat to warm the water in the tank. And the cold? If you feel the output behind the heater, you’ll see that the cold gets blown into the room. Heat the water, chill the room. Keep this in mind, we’ll come back to that later.

Why does a heat-pump water heater save energy?

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How to prevent your boiler from stealing your money

Energy Kinetics System 2000

Energy Kinetics System 2000

In the last article, “Is your boiler stealing your money?“, I discussed why most boilers are ripping you off. Contrary to what almost every HVAC saleperson or tech will tell you, your boiler does not operate at 84% efficiency. It doesn’t operate at 80%! Heck, much of the year, it doesn’t operate at 50% efficiency!

To review, the reasons for this include:

  • High operating temperature
  • Minimal insulation
  • Infrequent use
  • → Outrageously high standby losses

In this article, I’m going to discuss how to do it right. But if you’re too lazy to read the entire article, stop right here and go to the Energy Kinetics website.

But first, I’m going to save you $10,000….

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Is your boiler stealing your money?

Boilers - notorious energy hogs

If you have a boiler, chances are, it’s wasting a lot of energy!

At today’s fuel oil costs, (~$3.50/gallon in March 2011), it’s more important than ever to conserve. This is definitely one of those cases where it pays to do your homework.

What if I told you there’s a good chance that your boiler is half as efficient as they told you? You wouldn’t be happy, would you?

Let me tell you a personal story. When I moved in my house, it had a relatively modern boiler, rated at 82% efficiency. It heated the houe and the water. I figured that was pretty good – no need to upgrade, right?

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