200w/500w/1kw/4kw/5kw

[sweetwind]

Hi

Might be a dumb query. When i was going thru the articles here, many say 5kw/4kw etc. Is it for 5kw/second or /hr i really wanted to know about it, in that case 5000x60x60

will it produce 18000000watts? Horizontal Mills for home advertisements in news paper states that 1.3megawatt ?

after hugh's document the device i tried produces 35watt/s on an average for nearly 4 hrs a day. only one deviation in preparation, instead of hawt it is vawt .

[rossw]

Please do some research. This has been answered dozens, perhaps hundreds of times.

Watts is an instantaneous measure.

Producing 35 watts constantly, for a whole hour will make 35 watt-hours or 0.035 kilowatt-hours.

If you produce 35 watts constantly, 24 hours a day for a whole year, it will make 12.7 kilowatt-hours in the year, but it's still only producing 0.035 kilowatts.

I've seen some turbines advertised by how much power they "might" make in a month, based on some guesstimate of the wind conditions at the site. Take them all with a large spoon of salt

[DamonHD]

35W is just short of 1kWh per day (thus just over 300kWh per year), methinks, or has my mind turned to mush?

http://www.youtube.com/watch?v=oRQB2YXUxvY for the 40W bulb analogy.  (Disclaimer: I'm doing some work for this bloke.)

Rgds

Damon

[DanB]

To expand on what RossW has said...

You misunderstand the units here.

Watts is a measure of 'power'... sort of like 'horsepower' (also a unit of power).  So a 2kW wind turbine is 'sort' of like a 3 horsepower engine.  It doesn't tell you anything about 'energy'... the engine could be off... on.. still in the box, doesn't matter!

Watt Hours is a unit of 'energy' either produced, or consumed.  A 100 Watt light bulb, left on for 10 hours will consume 1000 Watt hours (or 1kW hour) - just the same as a 2kW wind turbine in a steady 10mph wind for 10 hours, generating perhaps 200W might generate 2000 Watt hours (or 2kW hours).

So power ratings for wind turbines dont mean a lot...  just like the horsepower under the hood of your car doesn't mean much.  I could drive my old volvo  with its 100 horsepower engine 1000 miles... or you could drive your corvette with a 300 hp engine 1000 miles, at the end of the day the same 'work' was done.

How much energy a wind turbine generates depends on swept area (how big is the rotor) and wind speed...  the power rating of the turbine is not terribly important except for marketing purposes in most cases.  (if you want to sell a wind turbine, big numbers seem to help because most folks don't know better)

[rossw]

<blush>

Brain fade. Been doing too many things all day and still trying to juggle too many when I replied to that.

Yes, 35W instantaneous, for a whole 24 hours is 840 watt-hours per day (0.84 kilowatt-hours), or 306 kilowatt-hours per year if it produced that all day every day.