One of the legacies of the electricity crisis of 2000 and 2001 is that it is now illegal for Californians to buy and sell electricity on the open market. If I have a spare kilowatt and you need one, too bad. I can no more sell it to you legally than I could deliver a kilo of cocaine to your front door.

We are right back where we were 10 years ago, when monopoly utilities, mandates from lawmakers and limits on trade left Californians paying 50 percent more for their juice than the average rates in the rest of the country.

But with new shortages of electricity looming on the horizon, the idea of letting at least some customers shop around for their power is making a comeback. And if done correctly this time, customer choice could be good for the big companies that are most likely to try it - and for the rest of us.

Something has to be done, and quickly. As California's economy starts to grow again and energy usage creeps upward, the supply of electricity is barely enough to keep the lights on.

A report last fall from the people who operate California's electricity grid showed that the state will have about 6,000 megawatts to spare during peak hours this summer if supplies perform as expected and demand follows historic norms. But a pinch in supply combined with an abnormally warm summer could turn that surplus into a shortfall. And with each passing year, the forecast shows the surplus shrinking and the chance of outages increasing.

The simplest way to avoid such a scenario would be a return to the past: Order the monopoly utilities to buy or build enough electricity to serve the growing demand, and pay them whatever it costs to do so, plus a guaranteed profit. Outlaw any competition.

The problem with this approach is that it puts all the financial risk on the users of electricity - us - and none on the suppliers. We must depend on government regulators to decide how many power plants we need, and what kind, and then let the utilities build and run them with no benchmark against which to judge their efficiency. We have to overbuild, almost by definition, to guard against scarcity, and innovation is suppressed. Once we commit to building a plant, we are stuck with it for decades, whether we need it or not. This approach is safe, but it can also be suffocating.

The alternative is customer choice. Find a way to let some electricity users buy their own power on the open market without jeopardizing those who are left behind in the regulated cocoon. This approach spreads the risk of building new plants to private energy providers and their customers. The state's biggest electricity users - factories, universities, big commercial operations - want this right and the obligations that come with it. It makes sense to give it to them.

Two bills pending in the Legislature would move the state in that direction. One of them, introduced by Assembly Speaker Fabian Nunez (D-Los Angeles) and backed strongly by Southern California Edison, nods toward customer choice but is not designed to encourage it. The bill's method for implementing choice is so unwieldy that it might never amount to much.

The other measure, by Assemblymen Keith Richman (R-Northridge) and Joe Canciamilla (D-Pittsburg) is better. Patterned after the way the natural gas industry works now, it would allow customers who use more than 500 kilowatts at peak to buy their own electricity from private providers, and it would allow the Public Utilities Commission to lower that threshold over time.

Both bills would require any customers who leave the regulated system to compensate the rest of us for their share of the pricey power contracts signed during the electricity crisis. And any customer who wanted back into the regulated system after leaving it would have to pay the spot-market price for any power the utilities are forced to buy on their behalf.

The hope is that freeing big customers to buy their own electricity will encourage suppliers to begin building power plants in California again. Not only would that increase the supply of electricity in the state, but privately run plants contracting directly with their customers would provide a benchmark against which to compare the performance of the regulated utilities. Opening up the market would also tend to encourage innovation, from "smart meters" that allow users to see how much their electricity is costing them in real time to distributed generation, through which even relatively small users can produce their own power where it is consumed.

Allowing consumer choice in electricity is risky, but no more so than walling ourselves off for years from the chance to get power at competitive prices.