Most solar panels will come with a 25-year performance guarantee, Barry Caslin from Teagasc told Tuesday night’s Renewables Roadshow event in Co Kilkenny.

The glass-foil type solar panel is the most standard type panel used on domestic houses in Ireland. These panels have a degradation rate of between 0.5% and 0.7% per year and they also decrease in output of electricity generation from year one compared to year 20, Caslin explained.

Glass panels

However, a more premium glass-on-glass product with a lower degradation rate is also available, but, in general, they cost 20% more than the glass foil.

“Glass-on-glass would be a more robust type panel and would be ideal in farmyard situations where you have ammonia emissions,” he said.

Installing solar panels is, he said, “something you only do once in your lifetime” and considerable consideration should be given to choosing what type of panels you use.