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How much Electricity do you use? How much can you REDUCE it?

Posted: Sun Feb 24, 2008 10:44 am
by NeilBlanchard
Greetings,

I just got a couple of the "Kill A Watt" meters at NewEgg, and that got me looking at my electric bill, with each month's total kilowatt hours listed. I figured out my household monthly average:

860.46KWH per month (averaged over a 13 month period)

That is with four people in a 1700SF house -- we heat with natural gas [edit: it's an old steam system!] as well as the hot water heater, clothes dryer, and cook stove -- all are gas, so the electrical covers: lighting, refrigerator, freezer, TV system, and three computers. We have at least 3/4 of our lights using CFL's (or LED).

[Edit 2: My refrigerator uses 1.6KWH per day (in the winter at least) so this is ~5% of the total, and we have a chest freezer in the basement that uses ~0.9KWH per day so that is ~3% of the total. I still need to find out what my computers use...]

How does your electricity usage compare?

Posted: Sun Feb 24, 2008 11:27 am
by aristide1
I've been in 2 types of gas heated areas, hot water and forced air, that do nasty things to the electric bill. Both require electricity for distribution. Apartments I've been in make good use of that fact and stick the tentant with the electric portion of the heat, yet still call it "free heat".

Now there's another type that doesn't need electricity; steam. but it's so damn inefficient nobody in the NE would voluntarily opt for it. Conventional gas hot water heaters have a similar problem. To run without electricity during the start/stop cycle it requires a pilot light to power a thermocouple.

$30 of each month's electric bill in the apartment is not shared in my case. It's the $30 constant for folding. The other folder is in my house.

Posted: Sun Feb 24, 2008 11:28 am
by Elvellon
About 600 KW-H per month. 5 people, 4 rooms, 4 CRT TVs (none of which I watch :)), 2 computers.

By the way, it's not kilowatt/hours because you multiply KW by H, not divide :).

Posted: Sun Feb 24, 2008 11:30 am
by aristide1
Elvellon wrote:About 600 KW-H per month. 5 people, 4 rooms, 4 TVs (none of which I watch :)), 2 computers.

By the way, it's not kilowatt/hours because you multiply KW by H, not divide :).
I think it's watts * hours / 1000.

Posted: Sun Feb 24, 2008 12:10 pm
by klankymen
no, its kilo (1000) times watts times hours

Posted: Sun Feb 24, 2008 12:25 pm
by Ralf Hutter
320KWH per month

That is with two people in a 800SF house -- we heat with natural gas as well as the hot water heater, clothes dryer, and cook stove -- all are gas, so the electrical covers: lighting, refrigerator, stereo, TV, and three computers. Probably about half the lights are CFLs.

Posted: Sun Feb 24, 2008 12:47 pm
by Palindroman
175KWH per month

That's with two adults and one child in a 75 square meter house (don't know how much that is in square ft). I've taken some new measures which will cut power consumption under 2000 kWh per year.

Remember however that every m3 of natural gas stands for 10 kWh. We consume around 1200 m3 of natural gas per year. In kilowatthours our total would be around 14.000 kWh, which is slightly more than 1150 kWh per month.

In a few months me and my family will move to the south of Germany where we will try to build a so-called 'passive house'. When done properly you can reduce your power consumption for heating with as much as 90%. This means we would probably require 3000 kWh per year. All we need then is a photovoltaic system on the roof that delivers 3000 Watts.

Posted: Sun Feb 24, 2008 3:31 pm
by truckman
Last month I used 459 KWH over a 28 day billing cycle. One person in a 2500 square foot house with natural gas heat, hot water, stove, and dryer. Almost all high usage bulbs are CFLs.

I'm guessing that about half my electricity consumption last month are from the five computers that I had running 24x7. Normally I only have four running:
  • personal computer/mail server
    work computer
    PVR
    firewall
but I needed to run one of my development machines full time last month. I've also got an assortment of network and KVM switches, DSL router, and CATV box that run full time. My computer monitor and TV are both LCD.

Posted: Sun Feb 24, 2008 6:36 pm
by dragmor
For the last two years its been between 8.6 and 9.2 KWh/day (so ~265KWh/month).

For two people in an apartment it isn't bad and we don't have gas. The 50L hot water heater takes a fair junk and my Wife works from home. Before she moved in myself and a flat mate would use about 7KWh/day (smaller fridge, no one home during the day, etc).

No heating or AC ambient temps (10c to 40c) don't require it.

Posted: Sun Feb 24, 2008 7:11 pm
by ZircularLogic
Well, my number is worse than most of yours: just over 1400kWh last month. Thing is, electricity is the only source of energy for the house. Heat, hot water, cooking, laundry...everything. Except both dogs and both cats, which we like to count as heat sources as well. :D The house is ~1800 square feet (uhh...167 square meters?) in a mild (ok, warm) climate, fairly well insulated. (510 heating degree days (F) over the cycle, base 65F. For you metric folks, that's an average outside temperature of just under 9C with the thermostat set to about 19C.)

I ordered my kill-a-watt from NewEgg today when I realized how inexpensive they really are. I'm dying to know what the standby load is from all the junk I have plugged in and not doing anything. A spreadsheet maniac like myself ought to get weeks and weeks of entertainment out of this. I hope my fiancee doesn't kill me when she finds the hair dryer plugged into it...

Posted: Mon Feb 25, 2008 6:47 am
by quikkie
I have one of these, it clamps around the main power cable before it goes into the meter. I've only had it since october but I'll read it tonight and edit this post.

FWIW I have gas powered heating (too far north to need cooling) and hot water with a gas hob (but electric oven) in a 4 bed, 2 storey detached house.

The "idle" power usage of the house is about 0.3KWh.

EDIT: for the last three months my usage has varied between 380 and 470KWh

Posted: Mon Feb 25, 2008 12:14 pm
by Eagle156
About 2000kwh. That's what it takes to keep a horribly insulated all-electric apartment warm in the winter.

Posted: Mon Feb 25, 2008 2:59 pm
by mattthemuppet
I think we're at around 7000kWh a year, so between 550 and 600kWh per month. That's for 2 1/2 people, 3 bedroom bungalow with gas ducted heating and stove (hot water's electric). Haven't been in Melbourne for a whole year yet, but we'll probably use the gas heating for ~3mths and aircon intermitently for a couple of months - usually only when it goes above 30C inside. All lights are CFLs, ceiling, hotwater tank and fridge (!) are insulated (last 2 with some excellent double layer foam bubblewrap left over from our move). when it starts getting colder I'll add some DIY double glazing to the bedroom windows too.

Our biggest electricity consumers are our fridge, hotwater and washing machine (also our biggest water consumer). PC only uses 80-100W + 19in LCD and it isn't on for more than 3h a day. All of our greywater's collected for watering the garden as we're in the midst of a major drought.

Posted: Mon Feb 25, 2008 3:02 pm
by klankymen
Well, I just learned today that Kill-A-Watts have batteries - WTF?
Well maybe not the actual killawatt brand, but I busted out my power meter again and it wasn't working - I had to replace two watch style batteries in it. Apparently to power the screen, why it can't draw from house power I don't know.

Image

Posted: Mon Feb 25, 2008 3:18 pm
by Spare Tire
Doesn't it keep memory of the price per kWh and your total consumption to date? That's why it needs a battery, i don't have mine plugged in all the time.

Posted: Mon Feb 25, 2008 3:41 pm
by klankymen
Spare Tire wrote:Doesn't it keep memory of the price per kWh and your total consumption to date? That's why it needs a battery, i don't have mine plugged in all the time.
I guess it's something like that. Nonetheless, it is the first device I've ever seen that ran out of battery while plugged into a wall socket.

Posted: Tue Feb 26, 2008 4:35 am
by seraphyn
klankymen wrote:why it can't draw from house power I don't know.
I would assume that it need batteries because a wall socket gives too high a voltage. And reducing the vltage would require the Kill A Watt things to be more expensive and bigger.

Posted: Tue Feb 26, 2008 7:25 am
by NeilBlanchard
Hello,

I very much doubt that the P3 units I got from NewEgg have batteries, since they lose their display as soon as they are unplugged.

Let's not go too far off topic, please!

I am going to try to reduce our household usage, and I will post the monthly total. How much can you reduce your electricity use?

Posted: Wed Feb 27, 2008 7:23 am
by Palindroman
quikkie wrote:I have one of these, it clamps around the main power cable before it goes into the meter.
Here's another nifty monitoring system with which you can monitor all the appliances in your household. All the info goes to your PC. It's a Dutch patented invention: http://www.plugwise.com/en/

Only thing I don't like about it is the fact that alle the data is transmitted wirelessly. I was hoping some form of Power Line Communication was used but this doesn't seem to be the case.

I'm still looking for some kind of monitoring system for our 'passive house'.

If you really want to reduce power you have to know what goes where. It all starts with knowledge and transparency.

Posted: Wed Feb 27, 2008 11:01 am
by sea2stars
Interesting product. Wish the webpage had more info; FAQ is missing.

Posted: Wed Feb 27, 2008 1:54 pm
by dukla2000
Electricity - 214 kWh /month (average last 12 months)

Gas - 428 kWh /month (average last 12 months)

500 sq ft mostly single occupant. Much of the electricity is 'luxury' - PC folding 24/7 is circa 70kWh/month, tropical fish tanks are about 100kWh/month. Gas for central & water heating and most cooking. Gas @ 2.2p/kWh, electricity @ 6.368p/kWh.

Posted: Wed Feb 27, 2008 8:04 pm
by scdr
Palindroman wrote:
I'm still looking for some kind of monitoring system for our 'passive house'.

If you really want to reduce power you have to know what goes where. It all starts with knowledge and transparency.
Sorry about the off topic post, but I thought this monitoring system was kinda neat http://www.bwired.nl/Stroom.asp

Although when you look at the rest of this person's setup, I don't think you could call it a 'passive house' - looks pretty hyperactive to me.
http://www.bwired.nl

Edit: I checked a couple bills from last year.
Looks like about 900kwh/month summer, 1300 kwh/month winter.
(3 people, 3 story house, oil heat, electric water heater and a couple of electric heaters (in small rooms where spend a lot of time) No AC)
Lighting mostly by (non-compact) florescents (only choice for energy efficient lighting in the 70's to 80's.)

Posted: Wed Feb 27, 2008 8:33 pm
by Rusty075
Oh, I wanna play!

Over the 12 months I've used 10,214 kWh, so 851kWh/month for my one-person 900sf household. But....I'm also all electric, and for me the biggest electrical usage is no doubt the air conditioner. My highest usuage month is July, where I consume 3 and a half times more electricity than I did in November, my lowest month. And, although my average is pretty high, >75% of it is used during the "off peak" times, which saves both my wallet, and to an extent the environment.

Posted: Fri Feb 29, 2008 5:49 am
by Brian
Here's a handy result from Google Calculator that will help you compare the draw of your devices to your total consumption:

73 kWh/month = 100 Watts

I'm living in an 86 year old, uninsulated brick house in a cold climate with four other guys. All utilities included. So my monthly consumption is [something enormous]/5, which is probably still rather large.

A Solar Grand Plan

Posted: Thu Mar 06, 2008 9:52 am
by NeilBlanchard
Hello,

This is only slightly off topic:
* A massive switch from coal, oil, natural gas and nuclear power plants to solar power plants could supply 69 percent of the U.S.’s electricity and 35 percent of its total energy by 2050.
* A vast area of photovoltaic cells would have to be erected in the Southwest. Excess daytime energy would be stored as compressed air in underground caverns to be tapped during nighttime hours.
* Large solar concentrator power plants would be built as well.
* A new direct-current power transmission backbone would deliver solar electricity across the country.
* But $420 billion in subsidies from 2011 to 2050 would be required to fund the infrastructure and make it cost-competitive.
http://www.sciam.com/article.cfm?id=a-s ... lan&page=1
Here & Now blurb wrote:A recent study in Scientific American calls for 30,000 square miles of solar or photovoltaic panels to soak up the sun's rays in the American Southwest to provide America with all its energy needs. The plan would cost $400 billion, create 3 million new "green" jobs and shut down all of the country's coal plants. Ken Zweibel, lead author of the Scientific American study, tells us about his dream to switch America onto solar power.

Posted: Thu Mar 06, 2008 11:20 am
by Eagle156
How do you use so little power? Non-electric heating I suppose?

Posted: Thu Mar 06, 2008 11:32 am
by jhhoffma
Shut down ALL of the coal plants? Surely, there must be some defining characteristics that make nuclear, gas, and oil power plants undesirable or unmanageable in some areas given the diverse geophysical makeup in the US?

Maybe I just need better education in the necessities of the US power grid...

Posted: Thu Mar 06, 2008 12:38 pm
by NeilBlanchard
Hello,
Eagle156 wrote:How do you use so little power? Non-electric heating I suppose?
Whom are you referring to?

Posted: Fri Mar 07, 2008 5:44 am
by HueyCobra
Approximately 153.5 kWh per month (460.5 kWh averaged over eight 90-day periods) for one person in an apartment. However, the figure has spiked since replacing a 24/7 laptop with a Sempron 2800+, and after buying a Dell 3007WFP-HC (which can vampire draw as much as 12W when "off"). The most recent 90-day period used ~50% more than the first period.

Posted: Fri Mar 07, 2008 3:53 pm
by aristide1
424 KW, in a 2 bedroom apt with 2 guys. The fan for the forced air heat takes it toll in the winter. We noticed immediately when we turned down the thermostat just 2 degrees, and added another layer of clothes.


Now look at the folding costs @ 285 watts 24/7 is like 200KWs alone. That's why I pay $30 off the top of the electric bill and then we split the rest.

Not happy with my Black Edition, not at all.

PVC are bad news Neil, the materials used are all toxic. Direct Solar heat is cheaper to implement and won't have the toxic waste problem down the road. In that sense PVC is like nuclear fuel. There's gotta be a better way.

Anyway to catch all the hot air from BF?