Solar collectors/solar photovoltaic system

Hi,
Have any AAM contributors installed either of the following.
Solar Photovoltaic system which uses semi conductor material to convert engery into electricity.
Or
Solar collectors to transform sunlight into heat or more commonly heat water.
With the grants available from they look an interesting option,
Would love to hear back how efficient they are? what company you used to install, any problems, issues to look out for.
We are based in the Dublin area with a south facing roof, and are condidering using this as a main source for electricity and heating water, with a gas back boiler as secondary.

Regards,
Logans Run

PV's are unlikely to be able to do much more than power the lights in the house - which is both due to the huge amount of electricity used in most household appliances (which would probably surprise you) and the strength of PV's - so it would be practically impossible to use them as the main source for electricity.

Solar Collectors are far more effective though.