Recently someone posed a good question on our website, which I thought was worth sharing:
Sean's QUESTION: I'm perturbed to see Ecotricity as a mid ranking carbon emitter. It seems to me that Green Energy and Good Energy are buying energy from existing renewables, which if anything increases the price and moves the big companies away from renewables. Ecotricity are buidling a lot of new renewable capacity, which I suggest is pretty important, and this doesn't seem to figure in your league table. Perhaps I am wrong, but the whole issue is rather complicated and it seems to me that you should be promoting Ecotricity equally with Good Energy and Green Energy. My tuppence worth..."
Andrew's ANSWER: "Great Question Sean. For the last couple of years suppliers have been obliged to report these figures to the Government each year. It's commonly called "Fuel Mix data" or Carbon intensity and is measured in the grammes of CO2 per kilowatt hour of electricity made.
Ecotricity score better than many suppliers as they have a high proportion of zero-carbon generation, but still have an element of (cheaper) fossil fuel electricity. This enables them to offer a good price and invest some of the profits in building new capacity.
At the top end of the spectrum is Good Energy who are 100% renewable. In terms of Carbon emissions, their official fuel mix data reports zero CO2 / kWh.
If you'd like to look at it in more detail there's a good summary on http://www.electricityinfo.org/suppliers.php"
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