# termodynamic/phsics

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What characteristics should solar collectors have, to function in an optimal way?
Why should these properties be fulfilled?

If there is a water flow of 500 g / minute to a solar panel on one m2, how much water is heated up under optimal conditions during the passage of the collector? Expect that the collector is in Gothenburg and the calculation is done for one day in mid-June (noon)

• thermodynamics/physics - ,

If the calculation is done for a full day, or day-night, you would not use the noon value for the daily average.

Optimal conditions are obtained with a cloudless sky, with panels facing the sun. These conditions would seldom be achieved, and would require that the panels be tilted at variable azimuth and tilt angles during the day. The penels must also be enclosed under clear clean glass to minimize convective heat loss to air.

At optimum conditions in mid June at noon using optimally tilted panels you could, for a few hours, expect to collect about 1000 Watts of solar energy per meter of panel area. Even in Gothenburg.

For the temperature rise DeltaT under these condtions, solve this equation:

(mass flow rate)*DeltaT*(4.18 J/ C g)= 1000 J/s

The mass flow rate should be in g/s, which would be 8.3 g/s in this case. This leads to a DeltaT of 28 C.

24-hour averages for typical weather conditions using stationary tilted panels will probably be less that 10% of that value. There are published average insolation values for various locations in Europe.

• termodynamic/phsics - ,

i still need help plz

• termodynamic/phsics - ,

i need more explanation

• termodynamic/phsics - ,

Hi!

Can you explain how did you get this equation

(mass flow rate)*DeltaT*(4.18 J/ C g)= 1000 J/s