THOUSaNDS of Scottish homes will be heated by renewable energy if Labour wins power in May's Holyrood election, the party has promised.  Under the plans Labour says are worth about GBP70 million over the next four years, 10,000 homes would produce their own, renewable energy.  Scottish Labour leader Iain Gray claimed the "green housing revolution" would create hundreds of jobs and hand households massive fuel bill savings.  Mr Gray said the scheme would involve the Scottish Government working with local authorities to fit mainly existing social housing with solar panels, or other forms of community energy schemes such as renewable heat.  Labour said it would fund the policy with income generated through the UK government's feed-in tariffs scheme, under which households that generate their own electricity from renewable energy receive payments from energy suppliers.  Mr Gray pledged the scheme would be started within 100 days of a Labour administration being elected, with an agency called Energy Scotland launched to take forward the plan.  Mr Gray also said it was the party's ambition to make green-energy powered homes the standard way of fuelling social housing by 2020.  He said: "Labour's green deal will create hundreds of skilled jobs for young people, with an initial ambition of retro- fitting 10,000 homes and business premises with insulation, household and community renewables over the next Scottish Parliament.  "My ambition is to have more homes producing renewable energy than anywhere else in the UK. I want Scotland to lead the green housing revolution.  Labour said that the plan will create over 300 jobs and 750 traineeships and would deliver an annual saving on domestic fuel bills of GBP133 per house.