There are a couple of initiatives in HAckney right now to get people using photo voltaic solar cells to produce electricity on roofs.  I'm thinking of installing a system on my roof in Dalston.  It should produce a good proportion of my electricity but only during the day.  There's no storage but it can feed back to the local grid (I'm told).

The other attraction is a feed in tarrif (FIT) return on the investment (about £10k).  The whole carbon economy is fraught with complexity and greenwash but keeping money in a bank isn't exactly free of compromises. It's an attractive option if you have a south facing roof.  There's also the question of embedded carbon cost in making the solar panels but they last 25 years (at least) so the theory is they pay off in the end.

Anyone interested can find out more at Refurb N16. Also see London Rebuilding for an alternative scheme for those that can't afford the investment.