i know that a solar panel of square meter generate 000 watts on a clear and sunny day, but i need to know the time rate. is it 000 watts per day or per hour? Thanks.
000W/square meter is the standard input rate that solar panels are rated by. Watts are a rate, like miles per hour. Depending on the technology, you might get as much as 20% of that as an output of the panel. To determine the amount of power generated, you need to multiply the rate by time. Just like in a car, going 50mph for 5 hours sends you 250 miles. You look at the rating of the panel, if it is a 50 watt panel, in 5 hours AT THAT RATED INPUT, you would generate 250 watt hours (wh). You can find charts that tell you how many sun hours are available a day. As the sun is generally strongest at solar noon, it is weaker in the morning and afternoon. They have averaged the power of the sun throughout the day, and said for each location, how many hours equal to 000W/Msq are in a day. Five is a nice average number. So, if you figure 000W input in a square meter, 20% output, or 200W (the rate) times 5 sun hours (time) = 000Watt hours, or kilowatt hour ( kwh) (quantity) can be generated from a square meter of panels in a day.
watts per hour or day is a meaningless concept. Watts are joules per second, where joules are a unit of energy. Watts are the RATE of energy being used or generated. .
Actually, there's about 000W per square meter of optical power from the sun. Solar cells cannot collect all of that power though. In fact, most solar panels are only about 5% efficient (though some can be around 20%). So that means a solar panel that is square meter can only provide about 50W, not 000W. And that's only during peak sunlight hours.
This question was answered a few days ago. The Watt is the unit of of power, not the unit of energy. Energy is measured in Watt-Hours or Joules but not in Watts per unit time --- see the difference --- [] a Watt per hour v. [2] a Watt for an hour? The term, Watt per hour does not make any sense --- it is a bit like saying my car has 00 Horse Power per mile. You are right to say that the round figure for the power input of a solar panel is ,000 Watts per square metre, in the middle of the day when the sky is clear. Were the sun to shine for 0 hours per day in the summer, you could get as much as 7kWatt-Hours per day --- if you were very lucky. The roof area of a small house is no less then 50 square metres and this is more than big enough to supply all of you household energy needs but taking account of rainy days and taking account of the need to store the energy for night-time is an expensive problem, to satisfactorily overcome.
