Business Green: Climate change secretary Ed Miliband will today meet the “big six” energy companies to discuss how a £7bn national smart meter roll out can be achieved between 2010 and 2020. The UK’s biggest energy firms — Npower, EDF, British Gas, Scottish & Southern Energy, Scottish Power and E.ON — have agreed with the government that each will be responsible for providing smart meters that allow them to more accurately measure a home’s energy use to their customers. The energy …