The application I've been thinking about lately is concentrated light on solar panels. Usually, when you are talking about concentrated solar for PV (photovoltaic), you mean high concentrations (100-500 suns) focused on a few square centimeters of high efficiency (and expensive) triple-junction cells. I'm looking at much lower levels of concentration, say, 10 suns, concentrated on something very close to a normal solar panel.
According to backyard experimenters, typical solar panels seem to put out 1.5-2 times their rated output under concentrated light but the higher temps generated by multiple suns can ruin the panels. Though reflecting light onto heliostats is done frequently, I haven't seen the basic info of how hot surfaces get under 2x sun, 4x sun, 10x sun and so on -- preferably under different weather conditions. I'd like some data on how hot things get under multiple suns. Given this, one could pair mirror configurations to solar panels operating parameters.
We know too that solar panels waste most of the of solar energy that hits them since they're only sensitive to specific light frequencies (wikipedia et al). Ideally, one could concentrate, say 10 suns, on a PV panel. Prior to the panel, there would be filtration films to eliminate IR or UV rays and so reduce the heat load. The ideal configuration would be 10 suns filtered precisely by a film down to the small band of frequency that the panel uses. If 80% of the heat were filtered out (overly optimistic? yes.), then you're down to 2x sun. Tweak the panel to handle high heat and higher currents and go for it.
Admittedly, this is an experiment undertaken with plenty of ignorance There are multiple effects to worry about if you actually focused 10 suns on an off-the-shelf solar panel for a chunk of time. Overheating the panel say, or size of the wiring at the back of the panel. Would the panel need to be excessively doped to produce the desired current? Sure, who knows.
But for all it's flaws, I still want to focus 10 suns on a brick wall and measure the temperature. Then, add a filter and see how much it helps. I'll let you know the results. Then, back to heliostats.