We've been looking into solar electric power for our home.
As a part of the planning process, I've been trying to get a handle on our electrical usage and find ways to lower it. Reducing consumption has a huge impact on the cost of going solar. So far, we have gone from using 360 kWh in January down to 250 Kwh in June. My goal is an average consumption of 200 kWh per month. This will save us hundreds of thousands of yen (thousands of dollars) in the capital cost of the solar PV system.
Admittedly, part of the lower consumption during that time has to do with longer daylight hours, so isn't really long term savings, but most has been achieved by simply turning things off or unplugging them when they are not in use and changing out the two incandescent light bulbs we had in the house for compact fluorescents.
To make it easier, I've purchased rocker switches that plug into wall outlets and some power strips with individual switches as well. Computers, speakers, the ADSL modem and wireless router all have "wall wart" transformers that suck up energy and even if each is a small amount for each, taken together it is significant. Those, plus the TV, stereo, and DVD player can also be draining your wallet even when they are "off", so best to turn them off at the wall outlet. The new switches make it easy to shut everything down when we leave the house or before retiring for the night.
I've also adjusted the number of fluorescent tubes in our kitchen fixture which is the one that gets the most use. It has five 15-watt tubes and a switch to select either 3 or 5 tubes. We almost never use 5 and even 3 seemed brighter than necessary to me, so I removed the center tube. Now we can select 2 or 4 (30 watts or 60). May not seem like a lot, but it adds up over time. My SO didn't even notice a difference until I pointed it out a week later.
It is also helpful to see how much each electrical item uses on average. One way of course is to look at the label, but that does tell the whole story. For example, our refrigerator is rated at 123 watts and estimated to use 460 kWh per year. But such ratings can vary depending on many factors. Is the kitchen heated? If so, that will increase the work load on the refrigerator. Are the temperature settings for the refrigerator and freezer set properly? Do you keep it at least 75% full? (A full refrigerator stays cool more easily). Do you open the door a lot? Do you keep the coils clean? And so on.
I wanted to know how much electricity OUR refrigerator, the way WE used it, was consuming. To get that answer, I picked up the following gadget:
It is called "ecowatt model T3T-R1" and is basically a watt meter. It plugs into an outlet and then you plug the item to be measured into a receptacle at the bottom of it. I paid about $22 for it.
This model has a digital display that sequentially shows how long it has been plugged in, how many watts have been used, how much CO2 that represents if the power is coming from fossil fuels, how much the power is costing in yen (based on the current rate of 22 yen per kWh).
By learning where your electricity is going, you can adjust your use patterns and improve your home's efficiency.
For the refrigerator, I left the ecowatt plugged in for 3 days to get a good average (87.1 hours actually). The result: In 87.1 hours, it used 6.92 kWh, caused 3.82 kg of CO2 to be released, and cost us 152 yen. From that it is easy to calculate an average hourly rate of 79.5 watts, 57.2 kWh monthly, and 696 kWh per year (and CO2 emissions of 384 kg). Uh-oh! What happened to the manufacturer's estimated 460 kWh per year on the label? Glad I checked.
For you North American readers, there is a similar tool called "Kill A Watt" which actually has some features I like better than those of the ecowatt. Their basic model sells for about $20. You can check that out here: P3 Kill A Watt
I've learned that my refrigerator uses more electricity than I thought and represents 23% of my electric bill. I will be more mindful keeping things off the top of the refrigerator, not opening the door as often or for as long, and not staying in the kitchen with a heater on during winter months.
Next month we are getting a new refrigerator and I hope it will deliver on its efficiency promises - it is larger, but is supposed to use less electricity. It may well do so, since the new one is better insulated and has a lot more drawers and compartments within it, which means that all the cold air doesn't flow out every time the door is opened. We'll see.
Hmmm...I wonder what the microwave is costing us?
Thursday, July 03, 2008
Blogs I Like
- Ad B: Japan Navigator
- Adventures of a (Swedish) Salariman in Tokyo
- Amy: Blue Lotus
- Boing Boing: Wonderful Things
- Brendan: UNU OurWorld 2.0
- Hiroko & Rick: Itadakimasu
- Jared B: Tokyo Green Space
- Joan: Popcorn Homestead
- Jon: Toshogu or As I See Japan... From L.A.
- Justin B: The Rational Pessimist (Climate & Risk)
- Kat: Food Adventures in Japan
- Ken: KenElwood in semi-rural Japan
- Mari: Watashi to Tokyo
- MTC: Shisaku
- Otakimura: In The Pines
- P: Pacific Islander
- Peko Peko: Kyoto Foodie
- Richard H: Spike Japan
- Risa & Kirk: Savory Japan
- Robert: Pure Land Mountain
- Shizuoka Gourmet
- Ten Thousand Things
- Tom: Kitchen Garden in Japan
Links I Like
- News: About Sweden in English
- News: BBC
- News: Der Spiegel (Germany) in English
- News: Deutche Welle
- News: FT Asia (UK, EU)
- News: Kyoto Journal (Japan)
- News: NHK World Society & Others (Japan)
- News: People's Daily (China)
- News: Telegraph (UK)
- News: The Local (Sweden)
- News: Yomiuri Online (Japan)
- News: Yonhap (Korea)
- NGOs/News: Organic Consumers Association (US)
- NGOs: Amnesty
- NGOs: Consumers Union (US) Food
- NGOs: Consumers Union of Japan
- NGOs: Greenpeace
- NGOs: Greenz.jp
- NGOs: Japan for Sustainability
- NGOs: Japan Organic Agriculture Association
- NGOs: Japan Vegetarian Society
- Shops: Alishan Organic Center
- Shops: Eco to Waza (GreenJapan)
- Shops: Warabe Mura
- Stuff: Japan Probe