My local Seattle utility offers a "Green Up!" program where customers can pay extra on each bill to buy energy from more renewable sources. I'm signed up to contribute at the highest level ($12/month), but I'm wondering if this is an effective use of money. Do they actually purchase more renewable energy based on customers opting in, or would they have done so anyway?
List of US "Green Up!" providers
As an aside, it seems strange that the purchase options aren't actually based on metered usage.