Building new homes designed to emit zero carbon and harness renewable energy is a bold and necessary move – but what about the billions of homes already sucking up energy? They must be greened, according to Gordon Miller, editor of WhatGreenHome.com.

More than a quarter of Britain's carbon dioxide emissions come from the country's 24 million existing houses. If every household in Britain upgraded its loft insulation from an average 100 mm per house to the 270 mm recommended by the government, it could save enough energy to pay the fuel bills of 400,000 families for one year, according to The Energy Savings Trust. Even if only those who could afford to make the change would do it, it could save a significant amount of energy.

Many cities around the world are eyeing incentives for solar panels and other sources of renewable energy. But they must step it up if they really want to attract the average Joe Shmoe homeowner. Will Joe want to pay for (or be able to afford) thicker insulation, more energy efficient windows, solar panels, etc., without some sort of monetary incentive? Probably not. Tax breaks, discounts on products and/or energy bills, community projects and other fabulous ideas not yet invented must be established to eliminate or at least decrease the amount of dirty pollution from existing homes and buildings.