SOLAR TRACKING SYSTEMS

How does that work? The geometry and orbital mechanics are not obvious.

No. The solar cells are at the bottom of the trough and it is pointed at the sun as best you can (more or less). It can be made as a fold flat to carry lightweight device eg. wilderness mobile phone charger. Some of them charge a battery and then you plug in the phone later.

There are designs of non imaging flux concentrator that by construction guarantee that every light ray entering the external aperture will pass through a much smaller region of space after a finite number of relfections. The simplest such design has the panel at the base of two parabolic mirrors arranged so that the focus of one is at the base of the other and arranged much like the trough above.

These things come from HEP particle detectors but were first adopted by solar engineering projects in the 1970's OPEC induced oil crisis. At the moment moulded Fresnel lenses have the upper hand for compactness.

I built one in foil with a gain of ten and got a correspondingly larger output current from a toy PV cell of the sort found in calculators.

Unclear yet whether printable stable organic semiconductors will make thin film PV technology ubiquitous and dirt cheap or we will forever be stuck with highly refined silicon for this application.

TBH I never expected to see OLEDs get out of the lab or the organics they are based on get out of a researchers test tube.

Bad design then. The shape I agree is ugly but you can get modest gain fora relatively low additional cost compared to the active PV panel.

I agree. Pumped water storage is about the most easily realised with the ability to handle fairly hefty loads as either sink or source.

A couple of decent sized suns separated by enough space to have a Goldilocks zone and planets placed at the L4 & L5 Lagrange points where stable orbits in the fashion of the Trojan asteroids exist.

If they have mastered the art of moving planets around to order they could even put one at the unstable L1 point between the two suns to get continuous daylight with (at least) one sun always above the horizon.

The trick would be in having suns heavy enough for stable Lagrangian orbits in the Goldilocks zone that will also live for at least 5bn years or so. Dying stars tend to sterilise their neighbourhood.

I was thinking about the target at the end of the reflector but to the side would work, too.

Right, so why the pipe? The panel would naturally be a plane (segment).

You could mount those Solyndra tubes vertically, so all the suns could hit them.

Ok, a periscope derrangment (similar to a periscope antenna). That should work, but I can see a problem with getting even illumination across the entire target.

Reflective stainless steel sheet metal:

The obvious answer is that a pipe is easy, simple, cheap, and works well for a boiler. It won't work too well for solar electric (i.e. Solyndra) because only part part of the pipe is illuminated.

That's just a matter of reflector shape. The optics is pretty well known, though it doesn't have to be anything like "optical quality".

How long does it hold its reflectivity (dirt, water spots, and all).

OK, but we were discussing a solar concentrator and you seemed to be stuck on a small pipe. I'm just trying to figure out when we're talking past each other. ;-)

Look at the offset mount satellite antennas.

Not quite right.

The stove is some variant of a flux concentrator requires a compact target that presents a surface roughly normal to the ray paths.

The oven creates a well insulated hot region surrounded by mirrors and cooks much like a conventional hot air bulk oven. It can cook anything that will fit inside the hot box subject to how hot it gets inside.

The angle of accpetance isn't at all bad. Obviously the high the gain you try to obtain the narrower the acceptance angle becomes.

It is more like 0.9 or slightly better over most of the range of wavelengths.

That is a half of the same trick. You do have to be careful to make the array uniformly illuminated or it will choke on the weakest part.

Astonishing to me that they can get blue out of it without degrading the organic material very rapidly.

It is easier to do in practice with a horizontal axis but you have to allow for what happens if it ever breaks loose. The MRAO 5km telescope used a high speed lead and steel flywheel as backup power to stow the scopes to zenith in the event of a hard power failure during a storm.

It the effect as a pure kinetic energy if it broke loose was used as an exam question more than once. The Robot wars hypno-disk showed just how davastating a spinning disk can be (especially one with tungsten carbide cutters on the outside).

What did you conclude ?