Business Green: London Mayor Boris Johnson and the coalition of London Councils have this week officially commenced plans to curb energy use from at least 200,000 by 2012 with the launch of a series of trials designed to help up to 10,000 homes save energy. Under the scheme, residents in nine boroughs will be offered a free green home advisory service, including access to low carbon energy saving technologies such as more efficient light bulbs. Households in areas selected to take part in the trials …