Talk:Watt-hour
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kWh is an abbreviation, right? For kilowatthour or kilowatt-hour?
S.
Webster says kilowatt-hour -- Egil
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[edit] Identities
A 60 W light bulb consumes 60 W of power. This is the same as 60 J/s or 216,000 J/h or 60 W·s per second or 60 W·h per hour.
This makes no sense. 24.94.17.47 04:55, 22 Mar 2005 (UTC)
- What is the problem?--Patrick 09:24, 22 Mar 2005 (UTC)
[edit] B.O.T.U.
The B.O.T.U. is an alias ... for the kWh or the Wh?
- kWh --Ali@gwc.org.uk 20:18, 4 October 2005 (UTC)
[edit] The attempted demise of the KWh
In Australia, all our energy bills are now in joules (and their SI multiples).
While this does allow comparison between gas and electricity prices (for example), it also makes the electricity bill less intelligible to many. Many people would know the cost in KWh of having an electric radiator running overnight, or even of leaving a 60W light globe running 24/7, but wouldn't even try to calculate these costs in joules. Is this an example of disempowerment (no pun intended)? Food for thought? Andrewa 18:55, 19 October 2005 (UTC)
- It's an example of why decimal time would be a good idea! If there were 100 seconds in a minute and 100 minutes in an hour and ten hours in a day then conversion between watt-hours and joules would be simple power-of-ten multiplication/division. :-) --Ali@gwc.org.uk 12:23, 1 November 2005 (UTC)
[edit] Reasons for the request for help?
Without claiming myself as any kind of expert, what kind of help is needed in here? I noticed that the article got a bit repeating about the non-SI:ness (what a word there) of the unit, but the best I can figure out is comparison between other articles about non-SI units, and a comparison between another energy unit. Maybe that would reveal some directions where to develop this article. Santtus 17:23, 12 December 2005 (UTC)
- As a physicist, this page looks fine to me as is. Perhaps engineers would like to add more content? I am going to remove the request for expert help. If someone would like to put it back, they should say why here. Strait 18:04, 12 February 2006 (UTC)
[edit] approximate price in United States
I've never paid an electric bill yet, but about how much does a kWh cost?
- It depends on where you are. Some info:
- 8.94 cents/KWh, US avg, Mar 2005; 18.06 (max) Hawaii, 6.08 (min) Idaho.[1]
- 7.21 cents/kWh, US avg, 2002; 4.26 (min) Kentucky, 13.39 (max) Hawaii.[2]
- 20 cents/kWh, California, summer 2001.
- 8.3 cents/kWh, US avg, Jan 1998; family avg 800 kWh/month, $66.40.[3] Shawnc 15:42, 18 February 2006 (UTC)
- And in Manitoba, my April electricity bill works out to 6.246 cents Canadian per kwh, all taxes included. The tail block rate for domestic use over 175 kwh/month is 5.780 cents Canadian per kwh. This may be the lowest or 2nd lowest household electrical rate in North America. --Wtshymanski 23:38, 31 July 2006 (UTC)
[edit] Convenience of kWh vs Joule
The article states that the kWh "is a convenient unit because the energy usage of a typical home in one month is several hundred kilowatt-hours." Why is that more convenient than the Joule? A few hundred kWh is about 1000 MJ or 1 GJ, which seems just as convenient to me, with the added advantage that it's an SI unit. Or do I misunderstand what is meant here? If so, it could do with a rewrite. DirkvdM 09:40, 31 July 2006 (UTC)
- SI units aren't necessarily convenient units. Witness your own edits to your comment above! --Wtshymanski 23:34, 31 July 2006 (UTC)
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- That's not what this is about. I don't make a claim. The article does. I just question that and say that another unit is not less convenient (well actually, it is simply because it's an SI unit, but that's not the point). I don't get your second sentence. What do you mean by that? DirkvdM 12:42, 1 August 2006 (UTC)
Well, for one, it makes for easier calculation. If you havea 100W bulb runing for 1 hr/day, then in a 30-day month it uses 30*1*100 = 3000 watt-hours, or 3 kilowatt-hours. To calculate in joules, you need an additional factor of 3600 10,800,000 joules, or 10.8 megajoules. As long as you know how many watts an appliance uses, it's easy to calculate watt-hours based on hours of usage. Nik42 06:14, 25 August 2006 (UTC)
[edit] kWh/yr - seconds, hours and years
I just put back the bit about kWh/yr using three units of time in one unit. It was removed with the argument that it wouldn't be interresting info, but I think this discussion at the ref desk proves that some explanation is needed. It is a very confusing unit, so it needs a good explanation. As long as it doesn't have an article of its own (which it doesn't require) the explanation should be here. There are already several links to the section from mentions of kWh/yr in other articles. And I have inroduced the term here only recently, so there needs to be a section for it on Wikipedia. I'm just not sure whether that should be here or under watt. DirkvdM 19:09, 3 August 2006 (UTC)
[edit] Milli?
Milli-, kilo-, mega-, giga-, and tera- are the most-used prefixes.
How is milli- a commonly-used prefix? When is milliwatt-hour ever used? That would be the energy used by, e.g., a 100 watt bulb in .036 seconds! I'm taking the milli- out of that list Nik42 06:18, 25 August 2006 (UTC)
