Good Energy used to be the clear leader in green electricity in the UK. Now I get the feeling that this space is beginning to get competitive. Here's what I'd do if I were Good Energy and wanted to jump ahead of the crowd again.
Retire 100% of the ROCs
Toby at work showed me the Energy Watch comparison of how different tariffs treat ROCs and LECs. I would retire 100% of the ROCs and LECs. I realize that this would mean that the tariff would be very expensive, but hey, it's green!
In the UK most domestic electricity meters are manually read by a person in a van. A less carbon intensive method is to have wireless meters that are like a mobile phone stuck to an electricity meter. The meter is read by a computer ringing up the meter.
Electricity is cheapest at night, and most expensive in the evening. I should be able to set my dishwasher to come on at one o'clock in the morning and pay half the amount! I can't at the moment because my meter can't tell the difference between night and day, and I bet yours can't either. A half-hourly meter measures the amount of electricity used every half hour. Good Energy should install a HH meter in one's house.