I'm not an expert on the issue, but I have certain hopes -

They say wind can be used for as much as 20% of our electrical needs. I'm not sure if that includes using sky scrapers in metro areas as the towers for mounting wind turbines or not, but I'm hopeful that by using sky scrapers and by improving the turbine design we can increase our electrical generation capacity via wind a good bit beyond 20%.

They say solar could far exceed our energy needs, with the right infrastructure. The only problem with that is that after about 4pm the angle of the sun limits its output, which seems to suggest suppliments will be required even after solar technology reaches maturity.

Transportation is an interesting component of our energy delema, since it seems to beg the question: will we maintain a refueling infrastructure somewhat similar to what we have today? I hope not. My hope is that energy production will be decentralized. An electric vehicle could potentially supplement it's energy with a photovoltaic polymer - though it might require a plug in every other day or so to fully recharge the battery. A hydrogen fueled vehicle could potentially use water as fuel, but that becomes problematic in drought prone areas. It might also be an issue in colder tempuratures - if there are any by 2050. It would seem that water refueling stations should be much cheaper than hydrogen refueling or today's gasoline, but there are both technological and ideological hurdles to any of this.

I have this feeling that wind and PV energy as well as other renewable energies are greatly underestimated - because we have never rolled them out on a massive scale. The research is continuing as well, on increasing efficiency and on energy storage techniques. A car in 1900 was a bit shaky to own and run - well, renewables are probably equivalent now to 1910 or 1920. They work, but they will still experience a great deal of improvement over time. I can not prove this, but I have observed most innovations do follow that kind of curve, and renewables are doing so right now.

A comment was made that solar would not be very efficent after 4 PM. With increased efficeny in panels currently 15% efficent, and better storage batteries that will become less of an issue.Reforming the netmetering laws will also help.Currently the utilities will only rebate you up to the amouint of power you use annually.Power fed back into the grid beyond that they take for free.Naturally they still charge others for that power they did not purchase.

Thanks for joining in, Nancy. Yes, the netmetering laws, which are a patchwork of differing state and local laws, should be part of a national energy plan. Unbelievably, the outgoing US federal government has been fighting and continues to this day to fight against meaningful energy policy with all its "energy" for 8 years.

There is right now a rush to repeal regulations, reduce the effect of species protection laws, and generally weaken all environmental policies, by the Bush administration. Every outgoing president does some of this, but of course with the current administration the effects are particularly foolish.

I recommend an article in the Economist, Heat from the Street. Water is heated under an asphalt road during the summer and stored underground for winter heat. A separate storage space is used for cold water that is used for cooling in summer, including cooling the asphalt so that it will not degrade.

Geothermal energy is another source that is gaining attention.

There are ways to store energy from sun because heat can be generated, and heat can be stored.

I also agree that distributed energy makes the most sense. Different parts of the country will need different solutions based on what they have a surplus of.

David Blume wrote a book called Alcohol Can Be a Gas. I heard him speak, but since you needed to have 25 acres and 40 people to do his project, I didn't buy the book.

Blume says big industry works hard not to have supluses because their price per unit of whatever would go down.

Ordinary people can make jobs for themselves using excess biomass from plants that grow wild (ever heard of kudzu: it's the huge roots that let it take over). Making alcohol out of things like corn is OK if you use the corn sugars to make the alcohol, then feed the left-overs to cows, which do better with the sugar out.

The old corn stills blew up because bits of the tough corn shell got caught in the copper tubes and the pressure built up. Nobody would do it that way any more.

He also says the oil industry was behind Prohibition because any farmer could make alcohol to fuel his vehicles, in competition with oil. That is why the Bureau of Alcohol, Tobacco, and Firearms visits farmers who grow the best animals. It has been statistically likely that those farmers were feeding mash from alcohol production.

Brazilians figured this out as a country. Guess what got discovered right off their coast? The mess-up in undercutting the Brazilian alcohol industry this time is the war in Iraq and the credit mess. Not only is Brazil not falling for the price manipulations, but some of the world's billionaires aren't either.

I think an exact replay of the 70's is unlikely for the oil industry. Urban asthma victims may get a break this time.

Now you know why I chose Jade Queen for my on-line name. I am so jaded.

I can add to my list of conspiracies! Never heard about Prohibition as a way to avoid alcohol fuel, but I believe it. For example, it is well-known that oil and auto industries killed light rail where they sprang up in the USA.... worth billions of dollars. Getting a constitutional (Prohibition) amendment passed to prevent a low-cost fuel from gaining a foothold for 90 years - priceless.