Business Green: The Mayor of London’s plans to cut energy and tackle climate change could bring up to 15,000 jobs and contribute £600m a year to the capital’s economy by 2025, but only if City Hall continues to create the right incentives for green businesses. That is the conclusion of a major new study published yesterday by Ernst and Young, which warns that while London has the potential to establish itself as the “Low Carbon Capital”, it will face fierce competition from other world cities …