Area required for 1 kW

[vikas maurya]

Some where i read for 1 KW system area required is about 16 Sq m.
Please give comments on this and if it is true explain the method of calculation.

Second question : i have are of 800 sq m which is shadow free. i have calculated per day generation possible in this area by considering the insolation data of the location and efficiency of solar panel as.
Area = 800 sq m
average insolation = 5.73 kwh/sq m
So 800*5.73=4584 kwh
fficiency of panel is about 12%
per day generation = 4584 * 12%= 550 KWh
have i done right calculation?
From this point 550 KWh generation per day.... How i calculate PV size required?

Thanks

[MarineLiner]

[russ]

Mike, Sunking or Rich - please check to verify or correct. Pretty sure I made my one mistake for the year already but who knows for sure!

Better to work from daily insolation. For 5000 watts/m3/day - average annual insolation for my area. A number can be obtained from the NASA site for many places in the world.

For 1 meter square

1) 5000 watts/m2/day
2) Of the 5000 watts per day probably something like 85% is within usable hours (from my solar thermal system) similar to the 5 hour number
3) 16% panel efficiency
4) 80% system efficiency for grid tied - for off grid 50% is closer

5000 * 85% * 16% * 80% = 544 watts/m2/day useful electrical energy generated

Russ

[russ]

average insolation = 5.73 kwh/sq m

kW/m2/day - not kWh
Thanks

My message was too short to be accepted so I am typing this to lengthen it.

Russ

[Sunking]

Close enough Russ for a guestimate

[russ]

Thanks Sunking - The PV Watts site points out there can be up to 30% variance in results over time.

I enjoy reading where someone says 'my system performs exactly as PV Watts says it should'. PV Watts is an average over time - the only way it can be done.

Russ

[Sunking]

The PV Watts site points out there can be up to 30% variance in results over time.

That would be downward over time.

[russ]

That is one and also the variance from year to year.

Russ

[MarineLiner]

Mike, Sunking or Rich - please check to verify or correct. . . . . .

For 1 meter square

1) 5000 watts/m2/day
2) Of the 5000 watts per day probably something like 85% is within usable hours (from my solar thermal system) similar to the 5 hour number
3) 16% panel efficiency
4) 80% system efficiency for grid tied - for off grid 50% is closer

5000 * 85% * 16% * 80% = 544 watts/m2/day useful electrical energy generated

Russ

[russ]

The 1000 watts per m2 has no meaning in calculating what a system will do.

That is a number for a standard test only and not normally seen in most of the world.

Russ

[russ]

Right - Do you have any idea where the 5 hours comes from?

Do you have any idea how often per year a site receive 1000 watts/m2

Do you have any idea what daily insolation is or where to learn what that number is.

Taking a number from here and there and multiplying them together to come out with 13 kW rather than 9 kW (which is still a rough number) wasn't to sharp.

The 1000 watts/m2 * 5 hours is like multiplying goats and pigs to come up with chickens.

Russ

[vikas maurya]

5000 * 85% * 16% * 80% = 544 watts/m2/day useful electrical energy generated

Russ

now to obtain 544 w/m2/day............wat will be the panel size

i think for this 80 wp panel is enough......pls correct me if wrong

[Sunking]

now to obtain 544 w/m2/day............wat will be the panel size

i think for this 80 wp panel is enough......pls correct me if wrong

You are way off. The number is make believe assuming a 20% efficient panel of 1/mt2. But to answer your question a 200 watt panel that occupies 1/mt2. Realistically all you can buy in your country is around 10 to 12%, so cut the production in half.