The Accidental Smallholder Forum

Smallholding => Renewables => Topic started by: goosepimple on September 10, 2011, 09:15:53 pm

Title: new type of solar panels
Post by: goosepimple on September 10, 2011, 09:15:53 pm
Does anyone have any experience of these - whilst contemplating the solar panels thing, we came across a website that deals with a different kind of solar panel that uses refrigeration fluid and works in sun, rain, cloudy conditions and at night.  Its marketed by www.thermalreflections.co.uk (http://www.thermalreflections.co.uk).  I spoke to them at length and as we live in unsunny scotland it seems perfect for us, giving us enough hw and heating for our radiators in our old millers house.  We're not really interested in the tarrif thing, just want enough hw and heating (we move around a lot).
Title: Re: new type of solar panels
Post by: doganjo on September 10, 2011, 09:43:39 pm
Does anyone have any experience of these - whilst contemplating the solar panels thing, we came across a website that deals with a different kind of solar panel that uses refrigeration fluid and works in sun, rain, cloudy conditions and at night.  Its marketed by www.thermalreflections.co.uk (http://www.thermalreflections.co.uk).  I spoke to them at length and as we live in unsunny scotland it seems perfect for us, giving us enough hw and heating for our radiators in our old millers house.  We're not really interested in the tarrif thing, just want enough hw and heating (we move around a lot).
So is it not recognised enough for the Government to allow the feed in tariffs then?
Title: Re: new type of solar panels
Post by: goosepimple on September 11, 2011, 11:36:53 am
Its a new product - its for direct thermal heating (like solar thermal panels but not using water) not making electricity as with PV panels.  It costs circa 8k to install enough for family usage for heating and hot water requirements.  Sounds great in theory as it allows us to get rid of the lpg tank which would be great.
Title: Re: new type of solar panels
Post by: Fleecewife on September 11, 2011, 11:48:33 am
Sounds interesting.......
Title: Re: new type of solar panels
Post by: mab on September 11, 2011, 04:38:29 pm
Hmm - it's new to me but sounds a bit too good to be true.

As far as I can tell from their website, it's similar to an air-source heat pump, but uses a 'solar' panel for the heat collector rather than an air warmed radiator.

Quote
For example a 200 litre system with one panel will only consume 600 watts of electricity and yet can give out up to 1690 watts of heating.

- doesn't sound any better than an air source system in terms of efficiency, and at 8K may not be any cheaper.

I wouldn't rush into it - I'd want to know a lot more about how it compares to other technologies.

mab
Title: Re: new type of solar panels
Post by: Womble on September 11, 2011, 04:58:36 pm

LOL, it looks as though MAB has beaten me to it, whilst I was looking at the glossy brochure (I was evidently distracted for too long by the pics of the girl in the bath!!  ;D).

Quote
The eco-friendly fluid (refrigerant) enters the panel
as a cold pressurised liquid. As it circulates inside the
panel it absorbs heat from the atmosphere and
becomes a gas. When the gas leaves the panel it is
very warm. The warm gas then passes through a
heat exchanger coil inside the water cylinder and
gives up its heat to the water. Using a refrigerant
in the panels instead of water is the secret of the
success of this system.

OK, as MAB says, there must be something more going on than is quite stated. The 'warm gas' can't be all that warm on overcast days (leave a black sheet of metal (which is what their collectors are really) outside, and it will get a bit warm on an overcast day, but not THAT warm!). So in other words, there must be some sort of heat pump involved here, to 'magnify up' the heat (is that what they're alluding to with the 600W vs 1690W comparison perhaps?). If that's the case, then this technology needs to be compared against other heat pump type solutions, rather than standard solar panels, and as already stated, lots of research required before signing on any dotted lines!!

Title: Re: new type of solar panels
Post by: goosepimple on September 11, 2011, 08:01:58 pm
Hmmm, yes I agree and will be doing the research quickly as we are looking for solutions before winter sets in - we're renovating now in a big way including re-roofing so want to get to it quickly.  If it works great in summer then good, if it works reasonably the rest of the year but saves us electricity then that's a bonus.  We have back boilers and a water mill wheel giving electricity as part of the package here so I think it becomes a bespoke solution for us rather than a, 'good for all' resolution.  Keep you posted.
Title: Re: new type of solar panels
Post by: Norfolk Newby on September 17, 2011, 11:50:05 am
The idea looks nice but you should check the basics. 1.6 Kw of heat is possibly enough for a small bathroom but won't make a typical sitting room comfortable on a cold day. For that, you need at least 5 Kw and possibly more in really bad weather.

If you have  a central heating system already installed, you can get a fair idea of the heat needed to keep comfortable from the size of the radiators. A small radiator puts out about 2Kw of heat and a really large or double panel one 7-8. You can check this if you get a radiator catalogue from a heating company which lists the output of each of the radiators.

A couple of points on heat pumps. First of all they are similar to fridge or air conditioning compressors. They make some noise and they wear out. 10 years would be a reasonable life and then they need to be replaced.

A good heat pump system should be able to produce 4 times the heat of the electricity used. 6 times is possible with a good source of heat like the waste water from a power station. So a 3 times increase as quoted here is not very good particularly as it should have a good source of low grade heat. The multiplier is called a 'Coefficient of Performance'. You can find out more here:-

http://en.wikipedia.org/wiki/Coefficient_of_performance (http://en.wikipedia.org/wiki/Coefficient_of_performance)

or check with Google.

By the way, there is no technical reason why the heat pump could not be driven by a windmill using a drive belt or a bevel drive at the hub and a vertical shaft attached to the compressor. Some systems have been built using a small engine to drive the compressor and the waste heat from the engine is recovered as well making the output very high considering the size of the engine. Of course, you have noise and maintenance issues to deal with using an engine.
Title: Re: new type of solar panels
Post by: ellisr on September 17, 2011, 06:10:11 pm
This is a type of solar thermal but it seems very inefficient. Solar Thermal will be included in the FITS scheme as of next year
Title: Re: new type of solar panels
Post by: goosepimple on September 18, 2011, 03:00:35 pm
You know what, they could have had a sale, but they have been so slow I'm not convinced they know what they are doing and it has put us off, I'll investigate other companies this week.  How annoying! >:(
Title: Re: new type of solar panels
Post by: SallyintNorth on September 18, 2011, 03:21:52 pm
This is a type of solar thermal but it seems very inefficient. Solar Thermal will be included in the FITS scheme as of next year

Thanks ellisr.  It sounded like solar thermal to me, too, but I'm not an expert so kept quiet. (For once!)

Why I've posted is because of the acronym.  Yeehah.  (Is the sound of me getting on my hobby horse.)

Acronyms drive me up the wall!   Firstly because almost all of them, being so meaningless, eventually get expanded to say everything twice.  My current example is "electronic slaughter SET EID tags."  Since SET stands for Sheep Electronic Tag, and EID for Electronic Identification, the text in question actually reads, "electronic slaughter sheep electronic tag electronic identification tags."  ::)
Secondly, the meaning of the original phrase gets lost, the term becomes a word in its own right and then takes on a meaning that was never in the original.  My new example of this is what ellisr has quoted above!  FIT stands for Feed-In Tariff, which was designed to define the rate at which the energy producer would be paid for energy fed back into the grid.  Maybe I am about to be corrected, but my understanding of solar thermal is that it heats water, it does not produce electricity.  You use the heat locally, either by washing in the hot water or piping it around your radiators or by using a heat exchanger to extract the heat from the hot water into some other water or gas system that you then use directly.  In any of these scenarios, you are not feeding any energy back into the grid. 
So whilst I completely understand why the powers that be say things like, "Solar thermal will be included in the FITS scheme", it will continue to annoy me (until such time as I can no longer remember what acronym means, I guess.  :D)

Sorry.  Rant over.  Maybe I'd better start a Pedants' Corner.  :D
Title: Re: new type of solar panels
Post by: ellisr on September 18, 2011, 06:06:50 pm
Solar Thermal = hot water

Photo Voltaic (PV) = electricity
Title: Re: new type of solar panels
Post by: goosepimple on September 18, 2011, 07:20:10 pm
...and solar thermal can also do your heating but you may need to top up from your electricity supply if you find they are not running hot enough.
Don't worry! - lots of people are getting mixed up with the pv / solar thermal thing!