Something that I have also heard is that as well as just purchasing renewable energy, Google is also offsetting the carbon from their entire operations. So e.g. they calculate the average employee commute carbon emissions, or the carbon emitted in the supply chain for getting the free sushi to employee's mouths etc and offset that too.

I like that if it is true. I can't find anything specific on their report (1) - it is kinda vague: they say they're using renewable energy and are carbon-neutral in the same sentence, so not sure if that is just energy or the entire operation.

1 - https://sustainability.google/reports/environmental-report-2...

Relevant : https://www.sciencedaily.com/releases/2019/05/190523111408.h...

"100% renewables doesn't equal zero-carbon energy, and the difference is growing"

I buy 100% wind power at home, but its pretty much a scam I think. Of course when there isn't any wind I get coal/gas/nuclear generated power. The 99% of people who dont care dont care and its just a way to get some extra charge to some people who try to be green. I keep doing it to try to send some signal but might give up soon.

I've wonderd about buying "eco power", it's not like electrons have markings on them that say "I came from a generator attached to a wind turbine!". It's just that the wind turbines put some Megawatts into the pool and their buyers took the same amount of Megawatts.

Don't know where you are, but green energy providers, at least in the UK, either have a relationship with the producer where they buy directly from them, rather than from the grid, or buy specific types of energy from the grid. It IS possible to buy energy from a specific source and energy is traded constantly during the day on the energy exchange.

Bulb for example have more information about where their energy comes from: https://bulb.co.uk/energy/

The whole point is to send that signal, increasing demand for wind power, and increasing the budget for the company so they can invest in new turbines.