Many, many thanks all for the information and opinions supplied to this topic.
Yes, the Irish Government (awash with over subscribed taxes..or so they constantly inform us) have considerable Grant aid on offer to Solar Power Installers as well as for a range of other efficient and environmentally friendly energy sources.
Barry, The US Government's apparent lack of support for such projects is worrying, right enough.
In spite of Grants the installation cost would be expensive but, that needs to be offset against the future, hopefully reduced , water heating bills, right?