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cheaper != cheap.

I never said that they'd be able to use bargain basement thermal panels.

Still, Evergreen Es-A-210-Fa3
210 watt, 13% efficiency, 65"x37.5" = 2,438 square inches of collector(1.57m2). $587 each bought in a pallet of 28.

Cost by area: $374 m2
Power by area: 134 w/m2
Cost per watt: $2.79

A "ThermoPower-VDF30 should be around $1,244.
It's aperture is 2.67 m2. 94% absorbtion, 7% emission per the datasheet. 'Stagnation Temperature" > 428F

Cost by area: $466 m2 (okay, it's not cheaper per m2)
Power by area: 634 w/m2 (at 1000 w/m2) (almost 5 times the power though)
Cost per watt: $0.74

Conclusion: At 27% of the price, you'd have to be looking at a pretty hefty penalty for using an adsorption chiller for it to make sense to use electrical HVAC with solar electric panels. Also, in either case I'd consider utilizing additional reflectors to put more power to the relatively expensive collector.

Well, considering that these: http://www.siliconsolar.com/solar-garden-lights.html, have been around for many years, I think 'first' is a bit of a stretch. They may have made them CHEAPER, and longer lasting, or more useful, but certainly not FIRST.

Why didn't they plaster a few of these on the roof to run it on solar power during the day? above the clouds so great power generation. It probably doesn't make sense to only have enough to power everything and waste weight on batteries and extra power to store. Still this doesn't seem very futuristic to me. just a plausible example.. http://www.siliconsolar.com/flexible-solar-panels.html

I don't want to be skeptical, but...:

Scaled up, a similar engine could speed a spacecraft to Mars in less than a week.

Right, just like a scaled up ant could carry a house. In movies.

But as any junior engineer knows, you can't just scale things up linearly and expect linearly scaled integrity and results.

In other words, there are solar powered toy cars out there. But math and physics prevent us from simply "scaling" this up to drive actual cars with linearly scaled up speeds.

Just so you know, I'd like to point out two things:

1) The site you linked to regarding solar collector efficiencies talks about heat engines, and mentions nothing about water heating. It makes plenty of mention about blackbody radiation, though, unfortunately all the math about efficiencies is using Carnot formulas and using ambient air temperatures as a heat sink - neither of which apply to this scenario. Try again.

2) The PDF you linked to is a little outdated and talks about using air source heat pumps, not ground source heat pumps like we were talking about (Hence the piss-poor COP ratings). That's a slightly different ball game because air source devices need to operate over a much wider temperature range than ground source devices. Might wanna compare apples to apples instead.

A standard, flat, solar-water panel does peak out at around 60% efficiency (I'll chalk up the similarity between this industry standard value and the site you linked to as coincidence, because the way they were arrived at are completely different). However concentrating designs - or configurations more elaborate than "a bunch of pipes in a box" - can certainly achieve higher efficiencies. Non-concentrating evacuated tube designs get up to about 75% for example... and they work great in colder climates where heat pumps have a really hard time.

=Smidge=

He needs a solar charger and a good bunch of rechargeables batteries, when you are around the world, voltages are different (don't care really as a lot of devices are 90-240V compliant) and different plugs (bulky).

The solution is a battery charger that works with a solar panel, a quick google search bring me this http://www.siliconsolar.com/travel-solar-battery-c hargers.php

Unless you're hiking in the arctic or antarctic during winter (ok, or Seattle), why not just cary a solar battery charger?

Hmm, scrap cells from here get 1.3 Watts out of 2x4 inch. That is approx approx half size for 11.7WattHour per day, so five times better power/area.

That means even with DC systems that would get 5-15 miles/day of free driving, depending on how much roof area you have, and if you want to cover your hood...

That's enough to cover my commute!

Well, perhaps it's not generally applicable enough to be considered a "solution" so let's call it a "solar consideration" instead.

Anyway, although I was disappointed when Real Goods became part of Gaiam, they at least still have a decent selection of solar power devices, some of which (as I understand it) can power your laptop directly. Under the right conditions, this would easily allow you to keep the system powered for many more hours than the typical laptop battery would provide (although, for DVD watching, the darker environment that may be desired for viewing would be counterproductive for watching on solar power).

Anyway, just something to think about, and certainly Real Goods is not the only source of such items. I recently bought a small solar battery recharger from Silicon Solar, for example, and some of the products in their catalog would probably be workable for this too.

(Many caveats apply, of course, including the size/portability/convenience of the solar power device.)

You mention being under the canopy of a jungle, so this is probably less than helpful. However, never having been under a jungle canopy I don't know how much light you get. But this solar PDA charger would indicate it's at least possible to run a PDA device in remote areas for extended periods. Ever able to find a "hole" in the canopy to see the sun?