Designing a Solar Water Heater System for 4500 Gal Tank

[gideon0223]

The problem is designing a solar water heater system to keep a 4500 gal tank of water at 140F during the day.

The tank in question has the following properties:

5000gal Volume
4500gal water
It loses about 1.8 degrees F/hr if not heated.

I first need to figure out amount of energy needed to maintain temps.

I did this using the following math:

4500gal of solution times 8.3 lbs/gal of water = 37350lbs of solution

37350 * 1.8 = 67,230 BTU/h of energy needed.

Seems pretty straight forward so far? (Math Errors?)

How do I go about finding out how much collector area and efficiency of solar collectors and heat transfer?

 

[berkeman]

I googled solar water heater calculator, and got lots of good hits. Here's one of the first ones:

http://www.infinitepower.org/calc_waterheating.htm

You can use a similar google search to find other calculators if that one isn't exactly what you are looking for.

Welcome to the PF, BTW!