You are incorrigible.

At least, it's not the next step that's coming. Right now (despite the BMW 7-series Hydrogen, which was really just for PR), the two companies that are still going forward with hydrogen fuel cells as a really significant part of their plan are Honda and Mercedes.

Toyota, GM and most others are heading straight to plug-in hybrids (aiming for 2010 mass market release) which does give something which bypasses most of the liquid delivery system (they have a very, very small gasoline powered engine, mostly in case of emergencies).

Tesla is aiming for 2010-1011 with the next all-electric car, a sedan (unfortunately, the price is probably going to be around $60K, better than the roadster, which there is still little evidence they have delivered to many people, but, we'll see).

The issue isn't developing a car that can run on hydrogen, they've done that. They just can't make the fuel easily, cheaply, etc.

In any case, why is it necessary to have only one solution - I believe that's the problem we have now? If everyone goes to plug-in hybrids and electric, they have to, well, plug them in to the electricity grid which means the power has to come from somewhere. Where is it coming from? Coal? Natural gas? Nuclear? Wind? Solar?

I think a mix of solutions across fully electic, hybrid, possibly hydrogen, if they can get it to work, and next-generation bio-fuels, plus as much improvement and expansion of public transit as possible is the best solution. Why are people so eager to dump dependence on one set of energy companies for dependence on another set of them?

China has drastically lowered its rate of population growth, but the rate of growth of its CO2 emissions continues to climb.

China and the US are neck and neck in CO2 emissions, but have substantially different populations.

Policies target countries like India for population reduction, and ignore the US. But US CO2 emissions are 20 times per capita India's. Why not reduce the US population instead? Or that of Qatar?

Total human resource consumption (including pollution emission) does not have a one-to-one relationship with population. There are absolutely NO statistics that prove that such a relationship exists (not even for food or shelter). People who argue that there is such a relationship INVARIABLY refer to animal studies by analogy. Paul Erhlich's projections have long since been discredited, but still have a dangerous lock on discourse.

In the real world, population growth routinely UNDERESTIMATES growth in resource use. Humans are not rats. We can actually decrease population and at the same time increase demands on the environment. Population is simply an inadequate indicator of most environmental harm.

The argument that having less people means more for each person remaining may be true (or not), but it is not an environmental argument. The environment only reacts to how much total pollution is released, not to how many people released it.

It is kinda funny how you are trying to avoid admitting that lower human population could help save the Earth.

Are you making a joke or seriously suggesting that fuel problems can be solved by noting that "We're awash in used fry oil"? A little arithmetic shows that you could fuel up what, maybe four Hummers for a day with the used oil from one McDonalds?

From The Guardian article, as quoted by Andrew:

Senior development sources believe the report, completed in April, has not been published to avoid embarrassing President George Bush.

This is important information for policy makers. Failure to publish this report could mean continued hunger and death for the world's poorest. But it isn't published to spare poor ol' Preznit Bush. How touching.

I get it Rodian. You can use numbers (population), but I can't use numbers (consumption). You can use analogy (humans on earth = rats in a cage), but I can't critique the analogy.

Paul Ehrlich should get some sort of medal for closing so many minds, and allowing the biggest culprits in ecological disaster to shift responsibility to the most vulnerable--and least culpable--members of society.

I guess justifying class ideology beat classifying butterflies. But it's unfortunate that the misapplication of population studies through analogy set back the environmental movement by decades.

We're awash in used fry oil. So after it clogs our hearts and kills us we can pour it in our gas tanks. So we can toodle down the road to get some more killer grease to eat. And so on.

Maybe we should cut out the middle man and fuel our cars with the obese directly.

We used to have the agricultural complex whose demand was fairly predictable and so was supply except for unusual weather events which on a global average tended to be well average. We had the energy complex in which demand and supply were fairly predictable except when there were geo political events. However, the spill over from one market to another was limited. With the advent of bio-fuels we have now linked these two markets. Events in the energy market now spill over into the agricultural complex. Thus the threat to bomb Iran not only results in higher crude prices but also results in higher food prices. Rather than just hoard (or inventory if you prefer) crude speculators can hoard grains because the too can be converted into energy.

Last week the USDA announced that farmers were going to plant about a million more acres of corn- about 150Million bushels and corn prices fell 5%. Imagine the fall if over 2billion bushels were not being used. The drop would approximate the 75% quite closely.

Well, at least we're not arguing about numbers.

I never said a word about alternative fuels. I agree 100% that corn ethanol is not only wasteful, but harmful. I don't believe for a second that population control is the only thing we need to do. I support conservation efforts wholeheartedly. I ride a bike when I can, drive a small car when I can't, and buy local.

I do, however, think the population of this planet puts everyone in peril, and facing up to that should be our number one priority. If we can deal with that, and do all the other good things we should do, global prosperity is a real option. I want that.