As any who regularly read my work should be aware, I have a fascination with the power of feedback systems to foster behavioral change (and here and …) and help foster more Energy Smart practices and to hasten the adoption of Energy Smart/Energy COOL technologies. This guest post by Milly Watt (which, in this context, truly should be ‘milliwatt’) on a variety of household electricity feedback systems speaks directly to that passion …
This series is all about changing our behavior to reduce our impact on the earth. Chances are good that the electricity many of us use in our homes is generated by some fossil fuel. Whether you’re concerned about climate change, oil gushers, or just saving money on your power bill, there’s motivation to reduce the energy used in your home. When it comes to saving energy, there is no shortage of advice (e.g., reduce thermostat settings, insulate, replace light bulbs with CFLs, keep the refrigerator full). But how do you know what will do the most good to reduce electricity consumption in your house? You need data! Feedback is essential!
E.C.S.T.A.S.Y. — End Consumption, Save The Air & Sea, Y‘all!
A support group and discussion forum for those who want to kick the
habits of consumption that are damaging the world we live in.
It’s been demonstrated that feedback systems can change users’ behavior. Cars with dashboard displays give drivers information to help them drive more fuel efficiently. Similarly, there are a range of options available for understanding your home’s electricity use better so you can make informed choices.
In an earlier episode of ECSTASY, G2geek gave a great review of the Kill-a-Watt device. This is an inexpensive device (<$25) that plugs into an outlet and measures the electricity used by whatever you then plug into it. It allows you to isolate the energy cost of a particular appliance, assuming that it’s plugged into an accessible outlet. It doesn’t work for overhead lights or installed appliances like the dishwasher or oven.</p>
The next category of monitoring choices give information on the energy used by the whole house. These include monitors that read your electric meter, interfaces to smart meters provided by your power company, and monitors that install inside your electric panel (circuit breaker box).
The first type is “non-intrusive” in the sense that they attach to the outside of your electric meter and spy on it. They are relatively inexpensive (about $100) and easy to install. They claim to be capable of reading almost any electrical meter used in the US and Canada. They send data via wireless to a display unit in the house (within approx. 100 ft of the meter). These include the Blue Line PowerCost Monitor and Black and Decker Power Monitor. This type is a great choice if you want a simple installation. They show real-time energy use in kilowatt hours and in dollars at the current moment in time (within a few seconds), but do not track usage history. It does allow you to flip a light switch or turn on the oven and see the immediate effect.
Here’s a picture of how the PowerCost Monitor hooks onto a meter and sends its data to the display:
If your utility offers it, you can get some information without installing any type of special monitor at all. For example, the meter from our utility, Puget Sound Energy, transmits meter readings every 15 minutes or so (apparently not always reliably received). Customers can log in to their account and get day-to-day graphs and other analyses, such as an estimate of where the energy goes based on appliance information you supply and comparisons to similar houses in their area (however they define “similar”). Here’s the kind of graph we can get that shows our daily energy use compared to regional weather data:
The next type is installed inside the electrical panel. This is the type I have — “The Energy Detective,” TED 5000. I wrote about some initial adventures with TED in the Saturday Morning Home Repair Blog. It costs a bit more ($200-240 for the basic models) and requires installation. Although we decided to use our computers to display TED data, there is an optional stand-alone display unit available. The data are updated every few seconds and the TED software, called Footprints, can display various graphs and charts. It stores usage history so you can track progress over time. The software also allows definition of load profile events to allow tracking of up to five devices with recognizable load patterns (e.g., a 4.6kW increase may indicate the water heater kicking on).
This shows the kind of detailed data we get from TED Footprints:
This is 12 hours of minute data. It shows our ground-source heat pump (at 1:00), a few spikes where the water heater came on, the spiky behavior (at 5:00) which is our septic system’s pump, and cooking breakfast around 10:00.
If you have a partnering utility or if you install TED and send its data to Google, you can use the Google PowerMeter software. This allows you to view your home’s energy use from anywhere via the web. So if you are worried about whether you left the iron on as you are about to board the airplane on vacation, you can check. It also offers tools to predict usage, compare progress against an energy budget, or interact with other users in the PowerMeter community. TED sends data every 10 minutes and we can view graphs showing usage month-to-month, day-to-day, and during a day. They also estimate your always-on power. Here’s what the graphs look like:
This shows our TED data as displayed by the Google PowerMeter. It estimates our “always on” energy use at 8.3-8.6 kWh. From the more detailed TED data, we believe our daily “always on” usage is around 7.5 kWh. Using our Kill-a-Watt, we’ve figured out where approximately half of that is coming from.
Finally, there is a device available that can measure each individual circuit in your house. It is the PowerHouse Dynamics eMonitor. It is relatively expensive ($690) and involves installing multiple sensors in the electric panel (standard model provides 2 sensors for main input plus 22 more for individual circuits). That’s something you would probably want to hire an electrician to do. But it will give you much more detailed information than the single whole-house measurement of TED. The software gives you various ways of displaying per-circuit consumption. There is also a remote monitoring and management service available.
We have had experience with the Kill-a-Watt, utility-provided information, TED 5000, and Google PowerMeter using our TED data. The Kill-a-watt has been very useful in measuring individual devices that we suspect are contributing to our always-on power (e.g., idle computers, the HRV system, clocks). It’s in the always-on power that the vampires live. Those are the devices that draw power while providing no useful service like phone chargers left plugged in when not charging anything and TVs waiting for a remote control to turn them on. When we find one, it goes onto a switched power strip.
TED has had a huge impact. We discovered that our two highest power devices, the hot water heating system and our ground-source heat pump, weren’t working properly. We had hot water and heat, so it wasn’t that they were broken in a way that you’d immediately notice. TED helped us diagnose both problems and has paid for itself already.
On the graphs, we saw spikes every 30-45 minutes and lasting for 10 minutes, day and night, regardless of whether anyone was around. It turned out that our builder had installed a recirculating pump on the water heater and it was misconfigured, causing the water heater to come on too often. We turned recirculation off and we figure that has saved 28kWh/day or $80/month.
Then we discovered that the heat pump was short-cycling and trying to work in that mode for hours at a time. The repairman tried a standard fix, but it went bad again within a week. When we showed him the TED graphs of the behavior, it helped him figure out that he needed to replace the control logic board. He was really impressed with how useful the information was to him. Now that the heat pump is working properly, we’ve not only saved energy but also eliminated the extra stress on the unit that would have reduced its useful lifetime and required an early replacement.
I suspect that malfunctioning household appliances are a significant energy cost. They are just wasting energy without providing any added benefits for using more electricity. It takes good information to discover the problems when the appliances appear to be doing their jobs (we always had hot water and heat).
- Annie Leonard’s crucial movie, The Story of Stuff.
- An invaluable tool for calculating the ecological footprint of your lifestyle, from the good folks at Redefining Progress. What’s your score?
- SCRAP - a creative reuse center, store and workshop space. Donations of high quality, low cost, re-usable materials such as textiles, paper, jewelry findings, wood, buttons and plastics are collected from businesses, institutions and individuals then sorted, displayed and distributed by SCRAP for artists, educational and community groups. For more creative reuse centers around the country, click here.
- Profound and stimulating philosophical perspectives on sustainability, civilization and the role of human nature from Technoshaman Jason Godesky.
- Freecycle. The Freecycle Network™ is made up of 4,793 groups with 7,208,000 members across the globe. It’s a grassroots and entirely nonprofit movement of people who are giving (& getting) stuff for free in their own towns. It’s all about reuse and keeping good stuff out of landfills. Each local group is moderated by a local volunteer (them’s good people). Membership is free. To sign up, find your community by entering it into the search box above or by clicking on “Browse Groups” above the search box. Have fun!
The ECSTASY series thus far:
February 28: Introducing ECSTASY.
March 7: The Work of Julian Lee and Juliet Schor: Two Voices of Sanity.
March 10: G2Geek’s Measure The Power.
March 14: Earthfire
promoted Annie Leonard’s appearance in Washington, DC.
March 21: RL Miller tells us about Chickens.
March 24: G2Geek prompts an unbelievable discussion about the
difference between Consumerist Time and Hunter-Gatherer Time.
March 28: citisven shares a thought-provoking and aesthetically
satisfying look at the ways that one person’s trash is another person’s art materials.
April 4: WarrenS gives us the good word on Making Homemade Musical Instruments.
April 7: G2geek talks about what makes for robust and sustainable technology.
April 11: B Amer tells us how to find ECSTASY on our bicycles.
April 18: rb137 reviews Judith Levine’s book, “Not Buying It!”
April 25: mwmwm’s powerful rumination on our collective complicity in consumerism.
April 29: G2geek discusses the need for a new economic and emotional narrative.
May 2: WarrenS offers Eight Thoughts About Timescale.
May 6: G2geek talks about the ecological implications of Where You Keep Your Money.
May 9: rb137 gives us a powerful review of the role of “blood metals”
in our consumer electronics — “Your Cellphone is Killing People!”
May 13: G2geek gives us the backstory of neo-feudalism, with more promised in the weeks to come.