OT: Solar Water Heating...Anybody have one?

gjm · Post by **gjm** » Sun Oct 26, 2008 4:11 am

I have been offered to have a free Solar Powered water heating system installed in my home.
I want to know if any one has had experience with these.

Did it really save you money on your power bill?

Any unexpected benefits or problems?

I am wanting to compare this to other possible improvements to my home that will reduce monthly costs of living and point me towards sustainable resource use.

Thanks.

Homebelly · Post by **Homebelly** » Sun Oct 26, 2008 5:12 am

Yup..
My sister and bro inlaw have one.
The install was pretty steep, no pun intended.
I think they saved about a third off their yearly power bill, and they got a grant from aunty Helen. A lot of my friends over on Waiheke also have them, but they are the much older versions that seem to be basically copper tubing painted blac, still,, they manage to heat their hot water so i guess its all good.
If you can get a free one, and the people putting it in are all legit, i would say go for it!!

nate_D · Post by **nate_D** » Sun Oct 26, 2008 7:18 am

definitely go with that! for free?!?! yeah that's pretty awesome man. you save alot on your power bill. i just started working with a company that installs solar water heaters but i'm on the pv (photovoltaic) side. i'm pretty sure they pay for themselves within like 5 years but if you're getting it for free then def do it. in the u.s. there are tax incentives as well. not sure how that works on your side of the world. you should look into that. here's the website for a book i found last week on sustainable living. def worth checking out. it's got prices on a lot of stuff also. http://www.realgoods.com/

Bagatell · Post by **Bagatell** » Sun Oct 26, 2008 7:57 pm

Do it! I´ve only fired up the boiler a couple of times since having solar installed and reakon i will easily pay for it self within five years.

stutter · Post by **stutter** » Sun Oct 26, 2008 9:04 pm

Bagatell wrote:Location: Sierra Nevada, Spain

telekom · Post by **telekom** » Sun Oct 26, 2008 9:10 pm

It certainly depends on where you live (and since I live in a Glasgow tenement, I have no use for a solar water heater). I've seen pics of the homemade 70's variety, where it's basically a pipe full of water snaking over the roof in the sun, and that apparently worked. So yeah a modern system for free? Get in there. Read the small print first though.

thefool · Post by **thefool** » Sun Oct 26, 2008 9:19 pm

take it

gjm · Post by **gjm** » Sun Oct 26, 2008 9:40 pm

Thanks people for your comments.

Things I have noticed to date:

1. I can't find any information on the lifespan of Solar power water systems. Are there any major component replacements say after 10 years? How long do the photovoltic panels last etc.

2. The claims on NZ websites are that you can save up to 75% electricity used to heat the cylinder in summer and 25-45% in the winter. Its possible to save 1/3 to half of the electricity used to heat a cylinder. BUT, in a conventional system, modern hot water cylinders use approx 30% (or less) of the entire electricity consumption in a house hold. We are a family of five, and in a couple of years, all will be adults.

So the math for me is, at the moment anyway, savings of maybe half of the approx 30% portion of the electrical bill that represents heating water. So my last months power bill rounded was $250. So at the moment, I am looking at a $30-$40 per month reduction in my power bill, maybe approx $400 over the year.

The question is, can I do other things, or install systems that can equal or better the financial savings?

For instance, my house has no insulation (its a Kiwi thing). Many houses built in the top half of the North Island in the 60's-80's had maybe a token amount or ceiling insulation, and nothing more. Financial benefits Hmmmm, don't really know?

Or, maybe a big veggie garden, raised beds etc, to reduce food costs. I think I could easily save $30-$40 per month with home grown veg. My climate is one where we can grow outside all year round, and I have time and a lifestyle that would allow me to tend to a garden. ( I currently have a small garden anyways, I would just need to upscale it).

What about retro fitting halogen 12v lights through out the house?

Any other ideas that I should consider that would be a better use of the solar water installation money that would reduce my financial house hold expenses?

gjm · Post by **gjm** » Sun Oct 26, 2008 9:44 pm

Homebelly wrote:I think they saved about a third off their yearly power bill

Would be interesting to hear from people who can say for sure they saved that much on the overall power bill. So far, I can't do the math and get an overall 30% plus saving. I can currently see maybe 12%-15%.

Maybe I am looking at it wrong.

fishmonkey · Post by **fishmonkey** » Tue Oct 28, 2008 4:30 am

gjm wrote:
Homebelly wrote:I think they saved about a third off their yearly power bill
Would be interesting to hear from people who can say for sure they saved that much on the overall power bill. So far, I can't do the math and get an overall 30% plus saving. I can currently see maybe 12%-15%.

Maybe I am looking at it wrong.

is your whole house on electricity? or do you have gas too?

gjm · Post by **gjm** » Tue Oct 28, 2008 7:20 am

fishmonkey wrote:...is your whole house on electricity? or do you have gas too?

Yes, its all electricity.

On top of that, my dishwasher and washing machine don't use hot water from the hot water cylinder. They use an apparently economic way of heating only the water they use in their cycles. So it starts cold.

Thinking about it further, using numbers from government websites and the solar industries association, I can only realistic expect a saving of $8-$12 per week for an efficient installation. Basically, that's 2 x 2lt of milk, or a bag of potatoes and a lettuce or two per week.

Yes I would be reducing carbon emissions in the world somewhere by having this system, but I'm really scratching my head about the sense of it. I know its free and all, but could I invest upwards of $6k or more into my home and lifestyle some other way and save more than $10 per week?

forge · Post by **forge** » Tue Oct 28, 2008 9:49 am

telekom wrote: (and since I live in a Glasgow tenement, I have no use for a solar water heater).

the true humour of that statement is only really apparent to anyone who's spent any time there!

fatrabbit · Post by **fatrabbit** » Tue Oct 28, 2008 11:59 am

forge wrote:
telekom wrote: (and since I live in a Glasgow tenement, I have no use for a solar water heater).
the true humour of that statement is only really apparent to anyone who's spent any time there!

Doesn't he mean he doesn't have his own roof?

I thought solar water heaters worked quite well even if there wasn't constant sun?

ethios4 · Post by **ethios4** » Tue Oct 28, 2008 1:36 pm

We had solar water heater when I was a kid (early 80's). I remember there always being problems with it and it was expensive to fix....after awhile my parents stopped using it altogether. This was 20 years ago though, so I have no current experience.

We cut our electric bill in half a couple of months ago just by cleaning out all the filters for the air conditioning...there was some secret filter I'd never seen before.

Making food at home frees up tons of money, as well as not going out and paying for entertainment all the time.

We started saving all our glass jars from store-bought food, and now we have a great collection of glass food storage containers, all filled with nuts, rice, beans, etc bought at bulk prices. Nice!

mikemc · Post by **mikemc** » Tue Oct 28, 2008 1:43 pm

fatrabbit wrote:
forge wrote:
telekom wrote: (and since I live in a Glasgow tenement, I have no use for a solar water heater).
the true humour of that statement is only really apparent to anyone who's spent any time there!
Doesn't he mean he doesn't have his own roof?

I thought solar water heaters worked quite well even if there wasn't constant sun?

In the most extreme interpretation of the joke, he doesn't even have running water

Now this would be a solar electricity based heating, or a solar collector based heating (that's the one with the array of pipes)?

The solar collectors last a long time, we had one on our house, had it removed for work on the roof, but it's just pipes in a flat box with a window in one side and reflective metal in the other.

The photovoltaic cells, it depends on the type, and it would also depend on weather conditions. Find out the part/model number of any photovoltaic cells they would install and look that up online.

Read the fine print for sure. The roof unit install might be free but the interior piping and the collector tank might not, for example.

[edit] Solar collector heaters will work without constant daylight sun also photovoltaics, but photovoltaics especially need unimpeded direct sun, their efficiency decreases greatly if they are in any shade-- even a tree branch. (and nowhere gets constant sun, i mean, there's always night, right?) They are charging a bank of batteries, also.