So, we set a maximum cap on emissions, sell the rights in auction, which of course the worst producers (coal plants and heavy industry) will have to pay for. On the back end, we ENCOURAGE more utility use, thereby INCREASING demand (or at least not reducing it). They key is that the subsidies won't start rolling in until quite some time after the caps are set, so demand will increase, but only after capacity can't, at least, NOTWITHOUT INVESTMENT IN GREEN ENEGY :D
Basically, we give people incentive to use power without fear, then limit the power that can be produced "dirty", leaving only clean power to fill the gap. If the electricity prices remain regulated as they are in most places, and because the power industry is now mostly deregulated (meaning I can buy power from anyone, not just the local company), they'll have no choice but to either build more clean power plants to fill the gaps, or buy power from their competitors who generate clean power on their own already. Prices won't be able to be simply raised at will to accomodate the cost, so power companies who invest the most quickly will have more power to sell to others. Since most power companies are regionalized, in order to resell clean power across great distances, they'll be incentivised to add superconducting lines to the grid, further improving our infrastructure and efficiency.
As years go by, caps reduce, thereby eventually requiring all power to be clean. With proper incentives, say additional rebates for those who use electric powered cars, demand will further increase while also reducing the number of fuel burning cars. (additional legislation on engine makers can also help this process). As the grid expands to accomodate competitive power sharing, and as clean power (mostly only able to be generated in specific regions, mostly low in poulation by nature except for nuclear) becomes more common, shifting power from place to place as demad sees fit becomes easier and cheaper. Concentrated power farms will be able to resell power cheaper than regional co-ops, and the power companies that can't afford to go green will be absorbed into larger, cheaper to operate, more efficient major firms. ...and joe public really can't get screwed out of this because and power price increases can be offset by rebates via fines, auctions, and taxes.
This is a pure genius system. Without legistlating power companies to make specific improvements in a timely fashion, and dealing with fighting the beuarocracy of it, we're getting a simple law passed, one that Califirnia companies are mostly familiar with already, and as a side effect, market pressure to become green will be unsurmountable, and the timeline will likely be accelerated far beyond what we can do in congress.