Each game round, the electricity demand (in GW) in your region increases due to the fate of the Dice. It's up to you to build power stations to produce the required GW demand. This provides you with income, with which you can eventually close the old fossil power stations and replace them with sustainable power stations that do not emit CO2. You can trade GW surpluses and GW shortages with the other players or External Markets to balance supply and demand.