Solar Panels

godtabh

My parents are thinking of getting them installed and they've asked me to look into to them.

I've done a small bit of research and I've found that they can use the solar panels foe either direct electricity or say just heating the hot water.

So what I want to do is the following

Determine the typical annual energy demand for the house (was gona base this on esb bills)

Determine what sun is available in Dublin for a typical year (from what I read I need solar intensity MET Eirean maybe?)

So what I'm trying to do is strike a balance between solar PV and solar hot water systems for the roof area available.

Any one got any experience in this? Any good sights out there?

MacTheKnife1

If you have a south facing roof, pitched at about 30-40 degrees then you are in business. Cheapest is to heat water directly but will really only work from maybe March thru October. So for about 7 months you have good solar water heating, and about for 5 months it really is out of operation. Some people say they heat out of the panels in winter but reality is that they get very little.

MickLimk

Hot water only systems are probably the most effective with today's costs/technology. Have you thought as to how the solar electric contribution would be integrated into the house energy supply? This can increase the overall cost of those systems. I can point you in the direction of a reasonably cost-effective solar electric panel if you want (PM me) but I am biased towards solar thermal (hot water) systems.

MacTheKnife1 wrote: »

... but will really only work from maybe March thru October. So for about 7 months you have good solar water heating, and about for 5 months it really is out of operation. Some people say they heat out of the panels in winter but reality is that they get very little.

Depends on the setup. My own system at home was giving me 50 degree C water temperatures on the clear sunny days over Christmas and the cold sunny days in early January.

In fairness I do have a setup that's a little more complex than what I normally install so it's all dependent...

Have a look at the certification bodies for solar thermal which will give you an idea as to energy contribution. How are your folks heating their water at the moment? Are they using an immersion a lot?

http://www.solarenergy.ch/spf.php?lang=en&fam=1&tab=1

http://www.estif.org/solarkeymark/Links/Internal_links/database/collector-database-updated.htm

Independent

Hi Micklimk,
I want to know how to compare solar panels. All panels being on the same roof everything equal, what do i look for to find the energy output,
Thanks.

conor2949

Independent,

these links are useful for comparisons of solar performance

http://www.spf.ch/spf.php?lang=en&fam=1&tab=1

and

http://www.estif.org/solarkeymark/

hope that helps

conor2949

sinnerboy

OP you need a BER assesment to answer the queries as you pose them

Some solar installers can offer the BER service ( which they are allowed to do provided that they make it clear that they also install solar panels .)

MickLimk

Independent wrote: »

Hi Micklimk,
I want to know how to compare solar panels. All panels being on the same roof everything equal, what do i look for to find the energy output,
Thanks.

I tried explaining as best I could a while back in this thread. It may help understand some of the figures you can get on those certification sites.

http://www.boards.ie/vbulletin/showpost.php?p=56792850&postcount=5

MicktheMan

To the OP.
I wonder what the motivations of your parents are for the solar. Is it cost or carbon? The reason I ask is because I get asked the question a lot and what people dont seem to understand is that if they were to spend their money on reducing their space heating needs first (insulation, draught proofing, heating control ...) their return on investment is far greater than it would be if spent on solar for hot water. BTW, I am not negative on solar, it is great in the right situations.