Solar Power-is it worth it?

Cardew

shandypants5 wrote: »

Yeah wasnt really thinking of a pumped system at all.
Just using the mains pressure and redirecting/splitting it so I had 2 incoming supplies.
One cold and drinkable, one hot/tepid and just to feed the hot water tank.

The problem I can see is that plastic loft tanks are not suposed to hold hot water. (I remember the one that split recently in the news scalding a child.)

I am no plumber but you surely can't be allowed to feed mains water through old radiators on the roof etc and mix it with water in the HW tank???

Any heating has to be done thro' an indirect coil in the HW tank.

shandypants5

Cardew wrote: »

I am no plumber but you surely can't be allowed to feed mains water through old radiators on the roof etc and mix it with water in the HW tank???

Any heating has to be done thro' an indirect coil in the HW tank.

Well old Radiators would be a nono I agree as they have already had "dirty" water inside them.

But I was thinking of brand new black plastic waterpipe.
Similar to the stuff the waterboard use under the ground.
The pipe would be getting constantly refilled with new clean water so its no different from the pipes already underground. (just warmer)


I Got the idea years ago from a Green issues tv prog about a housing estate in Scotland.
The whole estate had 2 incoming supplies.
1 was as normal cold water.
The other came via a massive heat sink concrete block buried in the ground.

This means that even in the winter the water from the ground sink was coming in a couple of degrees warmer than the standard cold drinking water.

So it cost less to warm up into hot water.

I cant understand why all new builds arent like this.

All they did was dig a deep hole, lower a spiral water pipe into it and fill it with concrete. Totally maintainance free and the water comes out tepid all year round.

The only downside I can think of is bacteria growth in the "warm" water.
But as its constantly being renewed, is in an airtight pipe, and will always be heated to 60 before use by the house gas/electric, then I cant see it causing a problem.

*imagines himself sitting in a bath of hot pondwater*..lol

Cardew

Are not their regulations to prevent syphoning from mains water etc?

Perhaps the DIY forum would be able to advise, or even the water section as a couple of plumbers visit(canucklehead)

dekh

Cardew wrote: »

I am no plumber but you surely can't be allowed to feed mains water through old radiators on the roof etc and mix it with water in the HW tank???

Any heating has to be done thro' an indirect coil in the HW tank.

I seem to remember the rads were filled with coolant/antifreeze and a heat exchange coil but I'd need to find the site.

You couldn't link old stuff up to drinking water. But if they were flushed it could take the chill off an out door pool/tub.

Not that I could afford an outdoor pool or even a tub

I always fancied running an HEP turbine from the unmetered tap water, but they thought of that in the supply T&C :rolleyes:

annscullamus

And whilst all the numbers fly over the page, and arguments roar, I have sat in my kitchen off and on, since the thread started (May 22) and noted with a small smile how many days I have turned off my LPG Gas Boiler, as by the evening I have a full tank of hot water from my under £2000, no electric pump, simple, no clean, fitted 2005, solar panel. But I resign myself to the ridicule of men of science (with no solar panel!), just like a lamb to the slaughter..............Now dare I press the POST button.

dekh

annscullamus wrote: »

And whilst all the numbers fly over the page, and arguments roar, I have sat in my kitchen off and on, since the thread started (May 22) and noted with a small smile how many days I have turned off my LPG Gas Boiler, as by the evening I have a full tank of hot water from my under £2000, no electric pump, simple, no clean, fitted 2005, solar panel. But I resign myself to the ridicule of men of science (with no solar panel!), just like a lamb to the slaughter..............Now dare I press the POST button.

That's really good, especially for Skye. Plenty of daylight hours May/June/July. What about November/December/January when you need it and there aren't many ours of daylight and less with clear skies (though clouds aren't supposed to make a difference)?

Cost of fuel is a major factor as everyone has said, but even on mains gas with the 45% price hike predicted it still doesn't make sense.

Maybe in a few years when the cost of install is reasonable, the equipment is more efficient with long warranties, the industry is regulated and other fuel sources finally reach stupid prices it would be worth looking at again for average users.

Cardew

annscullamus wrote: »

And whilst all the numbers fly over the page, and arguments roar, I have sat in my kitchen off and on, since the thread started (May 22) and noted with a small smile how many days I have turned off my LPG Gas Boiler, as by the evening I have a full tank of hot water from my under £2000, no electric pump, simple, no clean, fitted 2005, solar panel. But I resign myself to the ridicule of men of science (with no solar panel!), just like a lamb to the slaughter..............Now dare I press the POST button.

Not wishing to get into another round of 'discussions' with annscullamus(who posted before on her system) a few points for other readers.

The firm that fitted it now install single panel systems from £3,699
However living in Scotland she got a huge grant(it didn't cost £3699 in 2005)

Actually the firm that fitted it (SolarTwin) had one of the best websites I had seen. - or at least honest websites. One of their quotes was:

"Independently tested, Solartwin delivered 1000 kWh (3.6 GJ) of clean green energy as solar hot water a year in UK."

Note 1,000kWh!! - say £30 if you have gas. etc etc I rang them and they said that their system would produce 800kWh in N Scotland to 1,300 in SW England so 1,000kWh was a reasonable average.

So there is absolutely no reason why you would face "ridicule" for your statement above; nobody is doubting you will get a tank full of hot water. However you are not claiming above that a system producing 800kWh is cost effective, regardless of your fuel being oil, LPG, oil or electricity.


Incidentally this is an interesting article:

http://business.timesonline.co.uk/tol/business/money/consumer_affairs/article1781343.ece

It warns of the pitfalls of getting solar fitted.

Perhaps the most interesting quote is from the Energy Saving Trust - a Government sponsored agency which is hardly likely to understate the savings from Solar.

although a letter to Mr Robinson from the firm states that up to 30% of a household’s energy bills could be saved with their panels – a more accurate figure would be 5.5%, according to figures from the Energy Saving Trust

annscullamus

Dear Dekh,
It is useless in the winter except on a very few really bright days, but it is still rising in the very long summer days at 7.30pm - 8pm. It has worked for me. The grant was 40% from the Gov. and still applies in Scotland - I think it is £300 flat in England. We definitely get a better deal on that front.

I no longer make claims, I simply watch the temp gauge rise. Solartwin were great, and when the pump failed last year from a joggled wire during more loft insulation fitment, they replaced it - all the way up here!

Cardew

annscullamus wrote: »

no electric pump,

and when the pump failed last year from a joggled wire

Powered by solar or not, it is still an electric pump which can, and will, fail.

mech_2

I've been thinking about DIY solar space heating for a while. I found this:

http://www.cansolair.com/features.htm

A solar collector which heats air directly. It looks like something I could build myself for very little cost (recycled materials, no messing about with plumbing), and if it doesn't work at all, all I have to do is patch up a couple of holes in the wall.

Basically there are columns of aluminium cans painted black and housed in an insulated box with a clear polycarbonate front. Air is drawn from the house and blown through the inside of the cans and back into the house under thermostatic control. I'd also make it shut down if the air in the collector wasn't getting above a set temperature. I'd have it venting into the main living area in my house, mounted on a south-facing wall (avoids messing about with the roof).

I wouldn't expect huge savings, but it just looks so easy to throw together that the contruction cost would be fairly small (plus some of my time). Though I suspect I'll never get a round twit.

Thoughts?