Act on CO2 at Home In the UK 27% of the carbon emitted is from our homes. It is very very difficult to make a home carbon neutral – but we can all do a few things to help bring down that percentage.

Where does electricity come from?

About two thirds of the electricity in the UK is generated by burning coal and gas in power stations. This releases millions of tonnes of carbon dioxide, the main gas responsible for climate change. Of the remaining electricity, around a quarter of the total comes from nuclear power stations, with just a few percentage points from renewable sources such as hydro, wind or solar.

What is a green energy tariff?

The Government's energy regulator, Ofgem, has consulted on what should form a green energy tariff, and issued some formal guidelines [PDF file] in February 2009. In essence, it requires that green tariffs should:

• be transparent, explaining clearly what does - or does not - form part of the green tariff;
• provide details of the source of electricity supplied in each period (year) by the supplier (and should not seek to move green supplies into a green tariff, leaving the residual tariffs "dirtier";
• support additional environmental benefits, which can be through investment in new sources, energy efficiency or through quality assured offsetting;
• submit to a formal process of accreditation under a scheme that is expected to be launched in late 2009.

Note that this does not mean that green tariffs have come from "100% renewable" energy (or from any other type of energy source). In selecting a green tariff, you may wish to compare both the source of the electricity and the selection of additionality benefits that form part of the tariff.