Should you install a solar water heater?

Question

Should you install a solar water heater? The average home has a 200 liter (50-60 gallon) hot-water tank, which is effectively drained and replenished three times per day. Assume that the entering tap water is 15 degrees C and is heated to 50 degrees C. Given an average energy from sunlight of 1.53 kJ/cm2 per day, how large would the collection area (in m2) of a solar water heater need to be if its efficiency is 28%? Assume that the price of a solar collector is $375/m2. How much would it cost to install this hot water system?

Answer 1

I don't see how you can go rwong installing it, be it for economic -, environmental  reasons or otherwise. In time, the system will undoubtedly pay for itself. There is also the safety factor. Propane can be volatile, something you don't have to worry about with solar. Hot water haeting systems aren't as high tech ( at laest  not some) as you might think. You could probaly even install some pretty primitive ones of your own making. You could put a flat rectangular box with a large surface area on you roof, paint it a flat black , and you'll be surpriced at how much it can heat water. And you could just buy the standard hot water heating panels, witha pressure relief valve, and a mechanical heat expansion solar tracking device, or a computer controlled tracking. Pool heating systems , for the most part are pretty primitive, consisting mostly of lots of small rubber tubes bunched together in a mat, all connected to a larger supply , feed and circulation tubes. You could even coil a bunch of metal tubes , and paint them a flat black for maximum absorbtion of solar heat. I'd go solar. All around it's a good idea.

Answer 2

it would help the evironment and save you money

Answer 3

From a purely cost-effective point of view it probably isn't feasible.

If you use natural gas, propane or oil to fire your water heater, you can determine its monthly cost by looking at your summer bills.  A solar system will only cover a portion of your water heating needs (realistically, around 35%).  You must consider the initial cost as well as the maintenance.  Solar water heating systems require controls, circulator pumps, storage tanks, solar collectors and lots of piping.  I'll bet that if instead of a solar heating system,  you invested the money a solar system would cost in a money market, that you could pay the hot-water portion of your fuel bill for the rest of your life.