Mitzyboy

So following on from my Iberdrola thread, and seeing as the general agreement is that a water heater eats electricity, does anyone have any knowledge of the real effects of fitting solar panels for heating water in Spain?

Is it effective all year
How many panels & of what size do you need.
Can the panels be ground mounted, rather than on the roof

Does anyone have ideas of average cost / savings?

In fact, has anyone had solar panels fitted for any form of energy in the house, and are thay happy with it?

Hillybilly

You would still require a "back up" means of heating water, a gas boiler.
The size of the panels and the tank would depend on your house's hot water usage.
Panels can be mounted on the ground if you have a suitable space with the right orientation and without shade but it's always preferable to mount the panels with the water tank (in fact these systems usually come with the panels mounted directly above the tank) and of couse your tank is best off on the roof otherwise your water will have to be pumped up to wherever you need it.
I think there have been several previous threads on this topic. Savings will be generated over a period of years. An off the shelf system can be bought for around 1500€ but cost will depend on your individual hot water requirements.

spain

dont know anything about solar but our gas water heater is very economical, 1 bottle probably lasts approx 3-4 weeks - it has an electronic ignition, you can also get hydro ignition

EsuriJohn

Yes they are effective in UK and we do not get 320 days of sunshine a year.

Depends how much hot water you want and how much you want to store for nighttime use. Friends in Cyprus have the standard rooftop set for Cyprus 2 panels mounted on a frame with a pressure tank immediatly beneath. These are starting to appear on Costa Esuri as we speak.

Yes they can.

However fitting them retrospectivly means a long payback period for the capital expenditure.

Old Lob

I've got solar water heating. It cost virtually nothing.

You use an old radiator painted black and a commercially available solar powered pump. You need a medium sized tank - a small one will not do.

Not quite as simple as that but the I don't pay for water heating any more.

I got the plans from the alternative energy centre in wales which is very good indeed. You can use an old bit of 12mm pipe even - you really would be surprised.

The commercially available systems are very expensive and not that much of an advantage and in principle are just the same as home made.

twyntub

I remember a friend telling me the story of a chap who used to sell these systems in Jersey.

He'd go around with a piece of tube telling people it contained a special (and very expensive) 'heat transfer fluid' - and having left said tube in the sun for a short while got people to marvel at how hot the tube had become.

He'd then charge them thousands for his miracle system.

Of course, the joke was that the miracle (and of course incredibly expensive) 'heat transfer fluid' was, of course, none other than... tap water!

Old Lob

http://www.cat.org.uk/index.tmpl?refer=index&init=1

There is the url dalek - someone has asked a serious question and we are trying to help!!

I've made one of these things and it was virtually no cost - you can buy the plans for about six quid on the website - I'd send you my copy but I don't want to end up in hot water.

twyntub

Err... I think you'll find if you read my post more carefully that this was my point! People have over the years managed to sell these systems for thousands and thousands... justifying the cost on things like 'expensive heat transfer fluid' for goodness knows how much per litre, etc, etc, when all you need (and all they use) is tap water!

So... just to recap... it's ain't rocket science, anyone can do it, it only needs tap water, and there have been plenty of salespeople over the years that have sold it as 'space age' miracle technology to gullible people.

Casa Santo Estevo

We have heard about a solar panel which works more efficiently than the older design. We think it is not made out of Glass and cells. It works even when it is really cloudy too. We think it is made in Portugal. I know too many thinks but we will do some research hopefully find more about this system.
A round here if they are on the ground they get nicked (especially small ones)

EsuriJohn

I always thought that in the sealed systems they used something a bit more sophisticated which does not freeze and will be added to water antifreeze perhaps!

Mitzyboy

This clearly needs a lot of researching doesn't it!
Theres only two of us, so our hot water needs aren't great and we shower, not bath.

Old Lob

There are indirect systems with antifreeze which pump the water through a coil in the boiler in a closed circuit. There are direct systems like we've described which heat the water and add it to the boiler. The anti freeze has no value other than preventing freezing and damage to the system but is only needed where it freezes!

Old Lob

We think it is not made out of Glass and cells. It works even when it is really cloudy too.

It is infra red radiation which heats the system not visible light. Infra red passes through clouds - well some of it (and not when it is 'really cloudy'). Unless there has been a rewrite to the laws of physics then what is being described is improved thermal efficiency rather than anything more clever. It will be due to the geometry of the water flow.

Fred James

[QUOTE=Mitzyboy;5940693] Does anyone have ideas of average cost / savings? QUOTE]

We looked at solar water heating when we built our house.

The minimum cost was 2000€. We decided the economics we not good enough. 2000€ in the bank at 3.5% yields 70€ a year. The cost of heating our water in a 200 litre tank, on a timer on off peak electricity is exactly 70€ a year.

On this basis the system would never pay off.

billgates

As long as the price of electricity doesn't go up of course, and as long as you have a reliable source of electricity.