Solon AG, Germany's first listed solar company back in 1998, has just bought a 10 kilowatt hour energy storage device from Canadian firm, VRB Power Systems.

This is an important development because Germany's solar market has hitherto only been grid-connected, without any local energy storage backup. Returns are generated by feeding the solar power straight back into the grid rather than using it yourself.

It's always been my view that this is a more efficient way to use solar power - at source with the batteries and use the grid as a backup.