14 replies to this topic

[saver]

Searched for this but couldn't find a topic, which surprises me as it's something I know from real life.

Was wondering if people here had experience with these, or had them installed?

In short:

Quote

Solar water heating systems use free heat from the sun to warm domestic hot water. A conventional boiler or immersion heater can be used to make the water hotter, or to provide hot water when solar energy is unavailable.

From http://www.energysav...r-water-heating

A friend of mine has one of these.
Seems like a great simple way to increase the temperature of the water stored in your home.

It will still need a temp boost to get to suitable shower or bathing levels, but if I remember my physics correctly, less energy will be needed to heat already warmed water.

A good idea, or one where the installation cost and material requirements sadly outweigh the potential gain from such a system?

[Phil]

Depending on the sun they can get quite hot, SCALDING HOT!!!  Any reputable design will include a tempering valve that injects cool water in the hot water outlet as a safety measure.

I had three 4x10 panels on my CA home it would actually get so hot it would shut down during the summer.  Through most of the year my water heater barely ran at all.  I had radiant floors and the panels supplied most of the heat in the winter months.

I think typical payback is 4-5 years if you do the work yourself.  Many on line stores will sell you a complete package.

[dziomek]

I have tried the "solar showers" designed for camping, and have had to add cold water so I could have a shower without feeling like I was being burned. I think it all depends on what time of year it is, as well as how long the water is in the "heater". I know in our climate we can exceed over 30 degrees Celsius during the summer, which would heat the water to a scalding point. The winters however can reach temperatures lower than minus 40; I'm not sure how hot the water would get then.

It would be a good system to incorporate into one's home, but the costs would most likely be prohibitive for many.

[artistry]

If you are handy and can perform the installation yourself, there would be savings there. But if I were going to consider the system, I would wait until the government subsides kick in, in 2013. The savings seem modest until then.

[Phil]

US subsidies are 30% of cost until 2016 no upper limit!  It's a tax credit not a deduction which means yuou can deduct it directly from your tax bill.

[saver]

Shame to hear the costs are so inhibitive to people at the moment.

I know it's not, but at my mate's it does just look like a load of black drainpipes on his roof!

[Phil]

If it looks like black drainpipes, that would seem to be a pool heater.  Hot water panels are totally enclosed like solar panels, a sheet of glass surrounded by a metal frame.  Solar pool heaters are a layer of black pipes tied together.  The hot water ones look much better.

Here's an example of solar water heaters: http://www.solardire...swh/aet/aet.htm

[dziomek]

Do the solar water heaters need to be installed on a roof or can they be installed on a support away from the main building like regular solar panels? I am trying to gather as much information as possible so I know what route is best to take when I am ready to have my own system installed. It is good to know what has worked for others in the past, so I can go to the retailer/installer and tell them exactly what I want. I figure if I go in knowledgeable there is less chance of being sold a system that is not going to work for me.

[Phil]

They can be ground mounted like Solar panels.  Make sure you tell your supplier where they are to be mounted.  Like solar panels, sun exposure is a must.

[Shortpoet-GTD]

Found this on the web-
solar water heater made from old beer bottles.
Here.

[dziomek]

Phil, on 04 June 2012 - 04:47 PM, said:

They can be ground mounted like Solar panels.  Make sure you tell your supplier where they are to be mounted.  Like solar panels, sun exposure is a must.

Thank you! It is good to know ahead of time exactly what is needed; I feel there's less of a chance of being charged for a ridiculously large system that I won't need. Unfortunately there are still many who think women know nothing of this sort of thing and try to take advantage of them.

[papitohead]

Solar water heaters are very common here in Puerto Rico. I built one in 1991 and placed two pressure relief valves. One in the output of the tank to the house line and one in the top of the tank. This I did because they get extremely hot here in the caribbean. Since then I rented my house and sold the system, but I am going to build another one in the next twelve months.

[Phil]

I'd love to heat my house with solar hot water.  We had three 4x10 panels in CA and they really cut down on the heating bills.  "She who must be obeyed" will make the final decision though.   With this and my solar panels I could be very close to energy neutral.  That would be sweet.

[jasonb]

Solar water heating does work, the black pipe as described is cheaper and works good enough in tropics, the other type is more expensive - called evacuated tube, but better in your more temperate regions as allows the light in to heat the water and also insulates the tube so that the heat does not escape. Systems mounted on your roof are passive and use gravity feed, if mounted lower then include a solar powered pump.

A practical example is that 30% of household electricity is used on geysers to heat water, yet California's rate is only 3% due to SWH. Many countries now have Rebates (even South Africa) which make it easier for people to install - contact local approved plumber and he should have info. Installing this would also have a benifit on your re-sale value.

[Phil]

You can have active on your roof.  In passive systems the panels are lower than the tank.  Evacuated tubes are expensive, the older copper pipe is less expensive and makes better sense in moderate environments.  Black pipe is typically used for pool heating, I don't think I'd trust it for potable water.

Like all things, if you can do the work yourself you can save a bundle, at least half.