[jamesqf]

Originally Posted by NeilBlanchard

...I don't think that the supply of uranium is infinite.

What is? The sun's going to burn out one of these days, too :-)

I'm not just talking about solar PV. And not all solar PV has the same dangerous materials. Thin film PV roofing is far less energy intensive to make, and the payoff time is only part of the return.

No, they have different dangerous materials. And it seems that when the solar cells are cheaper to make, they're also less efficient.

If you generate electricity locally to where you use it, you only need to produce what you use...

Big if, there. Lots of times you can't: how do you run e.g. the very energy-intensive processes needed to refine the silicon for solar panels off locally-generated electricity? You're still ignoring the gigantic gulf between "I can build a solar house and live off the grid", and running the whole industrial society that makes the tools & components that go into building that house.

Solar heat can be stored efficiently, and as the SA article suggests, other means like compressed air storage underground might be possible.

No, the heat can't be stored efficiently, unless your criterion of efficiency is a whole lot lower than mine. And while there are a lot of ways to store electricity (high-speed flywheels are my favorite), none of them come for free, and that just adds to the capital cost of your "free" solar power system.

Wind keeps blowing at night, and if you spread out the turbine over a large enough area, you'll get power all the time...

In the process incurring those transmission losses that you were avoiding just a couple of paragraphs back :-) Not to mention that if you pay attention to the weather, you'll find that the wind quite often doesn't blow at night. A usual pattern in many places is for the morning to be calm, with winds picking up into the afternoon and evening, then dying down near dawn.

Wave and tidal power is always going to be there.

Maybe, though it'd be more accurate to say that the waves and tides are always going to be there. Getting power from them is not quite there yet. Even when & if the bugs get worked out of the technology (and we need replacements for fossil fuels NOW, not "someday"), how is it going to affect the environment? What are the side effects of e.g. damming a tidal estuary?

Methane from sewage (human and animal) and plant waste and trash is a constant we can rely on. This produces a high quality (non-water soluble) nitrogen rich fertilizer, than can replace chemicals that we get from carbon fuels.

Sure, but that's only a small fraction of energy use. What do you do for the rest?

Biodiesel from jatophra or algae or soybeans etc. can be developed. Jatophra is a scrub bush that grows on marginal land in drought conditions, and produces oil in a non-edible fruit. Wood alcohol from fast growing willow trees.

Sure, but again, it's only going to produce a small fraction of what's needed, at an unknown cost to the environment.

Small scale hydro is always possible.

But there's only enough of it to generate a small fraction of the electricity needs of the country, and - once again - at an environmental cost.

Nothing is perfect, and there is no single solution. Diversity and distribution are key -- as is efficiency!

Just what I've been saying. Yet you want to leave out one important factor in that diversity, and the one which (because it provides reliable baseload generation to run the grid) allows all the rest to piggyback on it.

We need to grow and eat locally grown, organic food -- both because it is much better for you, and tastes much better -- but it also doesn't use natural gas to make fertilizer, and diesel to produce and ship it!

Which is a fine and good thing if you're lucky enough to live in a small town in say New England or the Midwest, but not exactly practical if you live in midtown Manhattan, downtown LA, or any other major urban area.

Carbon based fuels are "so yesterday" in terms of their long term availability and their huge effects in the global climate.

Err... Has anyone disagreed with that? Not me, that's for sure. It's exactly what I've been saying all along. We need to start getting off of fossil fuels ASAP (we really should have started in the '70s). The problem is that we have a perfectly viable, economic, proven technology that can replace a lot of fossil fuel - certainly all coal-fired electrical generation, for a start - which some people don't want to use because of sheer superstition.