In addition, the company that manufactured the SEGS plant claims that its latest-generation technology is 50 percent more efficient than the SEGS technology. That would imply a proportional reduction in the acreage requirement for an equal amount of electricity generation.

Anthracite is now a quite small portion of the coal industry, and its primary deposit in eastern Pennsylvania has been mostly depleted.

Mountaintop mining often doesn't glean anywhere near that much - I seem to recall a National Geographic caption about removing a hundred feet of rock for an 18 inche thick seam.

To foster a desire in people to conserve electricity: at some carefully predetermined and constantly readjusted billing rate--money will not be accepted anymore, but physical labor will be required.  You pay your bill by helping shovel spilled coal, working at a recycling center or community food bank, picking up trash along a road, weeding in a community garden, helping insulate homes for the elderly and poor, mentoring at a school, etc.

If someone wants to burn alot of juice to heat their pool or power their McMansion, then they can plan ahead on required community service of some kind.  No exceptions or substitutions allowed!  Just another wild and crazy idea of mine-- I am full of them.

Bob Shaw in Phx,Az  Are Humans Smarter than Yeast?

Thermal/PV solar plants will be mostly built in desert areas where the ecological impact will be miniscule, and may be even positive.

OTOH coal miners reclaim the land (enforced by law AFAIK) after the coal seam has been exhausted, allowing for its recovery in the long term. But still the polution from the tailings remains, potentially contaminating the ground water etc.

Either way looks like comparing apples to oranges to me.

Question:
Do concentrating solar plants require a lot of land?

Answer:
Relatively speaking, no. Consider the Hoover Dam. Lake Mead covers nearly 250 square miles. A Concentrating Solar Power system occupying only 10-20 square miles of land could generate as much power on an annual basis as the Hoover Dam did last year. Considering the land required for mining, concentrating solar power plants also use less land than coal power plants.

They actually say less.  Which, technically it should since coal will continue to use land, whereas solar will occupy fixed space for eternity.  That's really impossible to argue, but what we've been doing here is trying to figure out where the break even point is...that's a little trickier.

Solar Tres

Although the turbine will be only slightly larger than Solar Two's, the larger heliostat field and thermal storage system will enable the plant to operate 24 hours a day during the summer and have an annual capacity factor of approximately 65%.

Impressive.  This technology has always held the most promise to me.

The logical error was that you were comparing a 1400MW solar plant with a hypothetical 100% loaded 1400MW coal power plant  which you feed 24/7 with that coal trains. If the real world CPP is 80% utilised, this would mean the coal inputs will alse be 20% down. Anyway, no big deal.

I agree with your bottom line but I don't think you are using the correct arguments. Coal is not worse because it uses more land, it is worse because of the way it uses the land - this is the thing we need to concentrate.

Personally I am cautiously "for" solar power. What really concerns me are those capital costs and how much from them are predicated on cheap fossil fuels. If the end-to-end EROEI is as low as I think, any attempts to scale them up will look like a threadmill - running as hard as possible just to stay in place. PV looks like a better bet for potentially lower EREOEI in future than thermal, but both have a lot to prove yet.