Mrs. Aol previously posted this
http://www.askaboutmoney.com/showpost.php?p=414794&postcount=2 which refers to the build method she used.
The company they used are referenced in this recent article in Construct Ireland [broken link removed]
Couple of things I'd like to point out.
These houses pretty much meet the passive house standard. This means you literally need little or no heating. Even in the depths of winter.
I imagine the OP wants to know if a solar heating system can make a significant contribution to a "well built by irish standards" but nowhere near passive house. There is no evidence in this thread to suggest it can.
A house that needs very little heating is obviously going to be cheap to run. I would wonder in Mrs. Aols case if the solar heating system was removed from the house, would the pellet bills rise significantly, i.e. how much is it actually contributing?
I love the idea of a solar heating system. Regardless of what I've read however, I don't see anything that would suggest it's possible in any affordable way. Solar heating systems have been done in Germany\Austria from what I've read. But these depend on large thermal stores (up to 10,000 litre insulated storage tanks) that carry solar heated water over from the summer\autumn to be used in winter.
Also the build cost referenced in the above link (i.e. 3x stand build) would put that type of build beyond most peoples pockets. However, as an aside, I would like to note that at this point in time it's looking possible to get passive spec. for about 20% over standard build price. It wouldn't be the eco friendly breathable timber frame route but it wouldn't require much heating either.