> this does not actually mean the datacenters run on renewable sources Yes, this is a problem. Let's say the grid uses 100 imaginary units of power per year.

> this does not actually mean the datacenters run on renewable sources Yes, this is a problem. Let's say the grid uses 100 imaginary units of power per year. 50% is currently produced through solar and wind. Company A buys 50 units and company B buys 50 units a year, until company A gets a crisis of conscience and decides to go green. They manage to get a deal whereby they pay for a certificate that says that their 50 units is produced through renewables. Great. Company B, however, has customers who care less about green stuff so they just buy energy from the grid and "their" electricity is now just produced from fossil fuels. In this case has anything really changed? It's probably a good thing that Google is buying renewable energy: I expect it raises demand for renewables in some way and it's good politically for companies to compete for green credentials. But it doesn't seem to do that much.