UnPlug Stuff
WINNER: Best App Created Outside of Ontario
UnPlug Stuff uses Green Button data to helps you find ways to reduce your energy use by identifying your home's base and recurring loads. See how big your phantom load is. Learn how much energy those devices on timers are using. After following some easy suggestions for reducing those loads come back in 30 days and see your progress.
9 comments
Bruce MacDonald • almost 6 years ago
I like the Unplugged presentation on reoccurring and idle loads how it may affect the overall consumption (& $) over a 24/yearly cycle. The example of the old VCR in the extra bedroom, has me looking.
johnmat • almost 6 years ago
Idle load is an important concept, nice to see it get attention. But how do you determine idle load for a home (other than looking for recurring times of load bumps)?
Lisa Schmidt • almost 6 years ago
Thanks for the comments Johnmat. We look at 3 months of data to find the idle and recurring loads. The idle load is the consistent lowest load over the time period, the recurring load includes loads which consistently come on at the same time everyday over the time period. We through out a certain number of aberrations in the analysis. Hope that answers your question.
Steven Sherman • almost 6 years ago
Do you know what percentage of a typical home's energy consumption goes to idle loads?
Lisa Schmidt • almost 6 years ago
We've analyzed about 3,000 homes and the idle is typically between 30 to 50% which correlates pretty well with a study done at Stanford showing an idle load across 200,000 homes of 43%. Most people are usually surprised at how high their idle load is.
Steven Sherman • almost 6 years ago
You'll have to prove more details into those number. Are you including heating or cooling during idling? From what I've seen, you're an order of magnitude too high. Usually vampire losses / phantom loads / stand-by power are cited as 3-5% of a home's energy consumption.
- $100/year, ~5% of $1900/year average utility bills: https://www.energystar.gov/index.cfm?c=about.vampires
- The EIA cites about 10% (though only $100/year): http://www.eia.gov/kids/news_energy_vampires.cfm
Lisa Schmidt • almost 6 years ago
Thanks for the challenging question, seriously!
It's our belief, based on analysis of real homes, that the energystar number you quote is out of date. So let me try to convince you why we think this is true.
Our definition of an idle mode is the lowest, consistent energy reading recorded over a period of time, in this case 3 months. Green Button data commonly comes in either hourly or 15 minute so we look for the lowest, consistent value for the interval over the analysis period. We throw out a few really low numbers to eliminate noise.
The Idle Mode is the lowest reading in watts but the more important number is how many kWh the Idle Mode represents. Since the Idle Mode is, by definition, on 24/7 the kWh add up quickly. That's why we recommend that small reductions in the Idle Mode can have significant overall energy savings.
The Idle Mode consists of anything which is consuming energy during the interval represented by the Green Button data (usually 15min or 1 hour intervals). Common devices contributing to the idle load are: entertainment systems, computer systems, hot water recirculation pumps, whole house lighting systems, a plethora of small devices plugged in. Many of these devices -- DVDs, surround sound systems, fax machines -- have high standby loads. A refrigerator could potentially contribute to the base load if it cycles every hour. So could an A/C if it is cycling every hour, but this very, very rarely happens in our experience.
We were also surprised when we started seeing these numbers. In the a sample of 900 homes here in California the average Idle Mode was about 220W. We do see homes having an idle mode of 30-40W but they are rare. We have also analyzed homes with an Idle Mode in excess of 1kW.
You may have a very low idle mode, but if yours turned out to be surprisingly high walk around your home and count all the devices which are plugged in. You'll probably be surprised at how many you find. Many are not drawing any power, but many will be.
Most people are surprised to find out how high their idle mode is, but we've tested enough homes to stand behind our analysis. And given the increasing number of devices we plug in, it's likely to go higher.
Steven Sherman • almost 6 years ago
This is just constructive criticism, I think this is a great application and I definitely agree reducing stand-by losses can make a big impact but I still think you're over emphasizing it.
- I don't know the algorithm for how you determine your idle mode but regardless of what it is, the recommendations you make won't reduce a typical home's energy consumption by 30-50%. Unplugging stuff, using smart strips, and reprogramming timers would most likely be up to 10%; maybe 20% in some very bad homes.
- All appliances, electronics, and lighting (including use, not just stand-by) made up 35% of energy consumption according to the most recent RECS by the EIA. So again, the types of recommendations you make will only be a fraction of this. I'm sure this number has gone up in the last 5 years, especially in the electronics category, but at the same time, appliance and lighting efficiency standards are also increasing.(http://www.eia.gov/consumption/residential/)
- Based on the 900 homes you've analyzed you said the average was 220W which translates to 1927 kWh per year. According to the EIA, the average US home consumes 10,837 kWh per year, which would mean about 17.5%. (http://www.eia.gov/tools/faqs/faq.cfm?id=97&t=3)
Again, I just want this to be constructive feedback. Encouraging people to unplug stuff is great but if you're suggesting 30-50% reductions in consumption you're misleading them. I'd be curious to hear more details about your data and references but I still don't buy the 30-50% number as a representation of stand-by losses, it must be including something else.
Lisa Schmidt • almost 6 years ago
Thank you szsherman for the comments and I most certainly take them in the spirit you offer them -- constructively.
I agree, our recommendations would not reduce a home's energy consumption by 30-50%, and I didn't mean to leave that impression. I was making the claim based on both our research and research at Stanford that the typical home's base load, at least in PG&E territory, is in that range. The base load might represent a smaller percentage in homes with more extreme climates, but this figure holds for homes in the temperate coastal areas and the more extreme Central Valley. I'd be happy to share more details if you'd like to contact me at lisa@hea.com. I meant to suggest that users can usually reduce their base loads without a significant investment in time or money, and since the base load is a large percentage of their overall energy consumption, these trivial steps can add up to real energy savings. To achieve energy savings does not necessarily require large monetary investments and in fact, those investments may not pay off for a very long time. And because the cost is so high to make HVAC/envelope modifications, people may be discouraged from taking any energy saving steps, especially if they believe those are the only measures which make a real difference in their energy consumption.
With all due respect to the EIA, we believe their estimates are incorrect. Unless their methods have changed recently, they develop a picture of typical energy use by surveying a group of households and estimating. There seem to be 2 potential problems to this method: people don't have a good sense of the number of items they have plugged in and it is very time-consuming to true-up these estimates to actual energy bills. I would assert that people are under estimating the number of devices they have plugged in and that the EIA is not using accurate standby figures for what is actually recorded.
The 900 homes I mentioned above had an annual average consumption of 5741kWh/yr (based on data from smart meters) and an average idle mode of 238W, or 2085kWh/yr, or 36%. We continue to gather data on more homes and plan to publish the data when the energy efficiency programs have completed.
Thanks again for your comments. I agree that many of the people using our software are surprised by the size of their idle load, but when they start looking at their own home they are also very surprised by the number of devices they have plugged in.