Google claims that almost 1/3 of their electricity comes from renewable sources, and they allegedly buy carbon dioxide hoax rip-offsets for the remainder

Google discloses carbon footprint for the first time | Environment | guardian.co.uk

At around 1.5m tonnes of carbon, the energy usage of the online giant is on a par with the United Nations
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Google's carbon footprint is on a par with the United Nations, the internet giant revealed on Thursday as it published its energy usage for the first time.
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Today's announcement repeats the 0.2g figure and gives equivalent numbers for other Google services, such as YouTube (1g of CO2 for each 10 minutes of viewing) and Gmail (1.2kg of CO2 per year for the typical user). The company calculates that, in total, the typical Google user creates 1.46kg of CO2 by consuming its various services – the equivalent of filling a deep bath or buying an imported bottle of wine. It also claims that producing and shipping a single DVD uses as much energy as watching YouTube non-stop for three days.
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Almost one-third of the company's electricity comes from renewable sources – a figure that is continuing to rise. The company offsets the emissions generated by the remainder of its electricity supply, along with those from its offices and transport.