A solar installation so big - you could hit a barn door with it.

It's not just homeowners that can earn a pretty penny from a photovoltaic solar panel installation on their homes roof, as one Cambridgeshire farmer has shown.

The biggest solar panel array installation on a barn roof was completed last week (source Farmers Weekly).

The 504 panels (with a total weight of 9ton) will generate 100kw (on a sunny day) into an arrangement that pumps the spare energy into the national grid.

As Farmer Tim Breitmeyer pointed out, the installation atop the grain storage barn makes perfect sense as the bulk of the buildings energy requirements are during the summer months at harvest time.

The overall cost of the project was £340,000. Revenue from the Feed-in tariff as well as savings made on normal energy consumption are expected to total £30,000 a year - a figure expected to rise as the FiT payments increase with inflation annually.

The feed-in tariff currently pays 31.4p/kWh which will fall to 28.7p/kWh for new installations installed after the 1st April 2012.

photo credit: tony hisgett