PV Gap

Scott Said:

Where's the best place to get DIY Solar water heating kits in the uk?

We Answered:

BTW you can make one yourself - there is a video to instruct you how to create solar hot water using a black hose

Michelle Said:

Solar water heating system questions...?

We Answered:

Efficiency of the panels:
This has to be temperature related since you have no other data. A 100% efficient system would transfer all the heat from the panels to the water so for 100% efficient Twater/Tpanels would be 1. Of course you need to use the steady state temperature of the panels and the water...steady state is when the temp doesnt change any more.
Efficiency of the heat exchanger: Same principal as the panels use Temp of the water you heated / temperature of the water that is doing the heating. In the real world you would probably have a flow rate of the water and could calculate the actual heat values but temperature difference appears to be what this homework is all about.
Overall system efficiency is T panel / T water that was heated by the heat exchanger.

Oscar Said:

EAGA SOLAR WATER HEATING PROBLEMS?

We Answered:

From their website it seems that Eaga works in India, Uk, Canada and Ireland so I would assume you are from one of those places.

There are about 5 different general types of solar thermal installations using panels. I would also assume you have one of those installed. But each of these systems is configured differently and will have a slightly different mode of operation.

In some systems there is an anti freeze in the lines, in some systems there is only one pump. All of these types of systems are custom installed in a house and each configuration is not exactly like all of the others.

While I might agree it is possible that a pump has lost its prime. This may not be the whole story or it may not be the problem at all.

Your best approach is first try and have the installers troubleshoot the problem with the system.

If this is not possible then any plumber might have a look to determine on site where the trouble lies.

Pay close attention to the start up of the system to make sure that you are closing it down properly and know how to start it again. Congratulations on choosing such a system and good luck with it.

Ida Said:

Where do we find the cheapest, simplest plan for a solar water heating system to supplement our existing gas?

We Answered:

1st counter Q is:
What kind of SWH are you envisioning: Space heating? Swimming pool? floor heating? or are you trying to generate hot water for showers and other human-contact/human-consumption purposes?

The reason for all the counter-Q's: building a DIY non-potable SWH system is much easier than a clean drinking-water-quality system.

That said, I think this might be the cheapest:
http://www.iwilltry.org/b/projects/build…
or this
http://www.thesietch.org/projects/solart…