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This is mainly an engineering & economics question; and we can deal with those aspects of it over on the Sustainability Stack Exchange, if you want. And there is one conceptual physics aspect too. No, fresnel lenses are not widely used for solar power. Occasionally, but rarely. Concentrated solar power (CSP), including concentrated photovoltiacs (CPV) ...

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Fresnel lenses are not used, but fresnel reflectors may be soon. There are two main ways in which electricity is generated from sunlight: Photovoltaics: These (what are commonly thought of as "solar panels") are generally used without optics. The reason is that they will accept light from nearly any direction, and the power generated is directly ...

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Boden & Bagnall (pdf) looked at this question of reflection, in their paper Bio-Mimetic Subwavelength Surfaces for Near-Zero Reflection Sunrise to Sunset. Their estimate of the proportion of photons reflected, from sunrise to sunset, in a fixed PV system is 20%, rather than your estimate of one-third. The proposed etalon is not an efficient or ...

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If you want to know more beyond the physics concepts, please do ask over on the new Sustainability Stack Exchange, where we can cover the physics, economics and engineering of such a question. Here I'll deal with the physics (and only touch on the other aspects in passing) Technical feasibility Each of the bits of the system you propose happen in real ...

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Yes you can use the falling water to make electricity - that's how hydroelectric dams work. But if you are using power to pump water back up then you will always use more energy to pump it up than you get back from falling down. Otherwise you have a perpetual motion machine The only way it makes sense is if you need to pump the water up for other reasons ...

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The trouble with an etalon is getting the light into it in the first place. Bearing in mind we want normal inidence to maximise the light intensity our solar panel looks something like: But solar panels aren't transparent (obviously since they reflect two thirds of the incident light) so if you wanted to use a second panel you'd need something like: ...

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Ballpark estimate, I'm not a geoscientist so I don't kn ow if the whole idea even makes sense: This abstract of a paywalled articel states $4*10^{10} W$ Energy release and a mass flux of $3 * 10^4 kg s^{-1}$. So we are talking roundabout $1.3*10^6 J kg^{-1}$. A supervolcano eruption is typically defined as yielding more than $450 km^3$ magma. Assuming a ...

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Short answer: On something operating with non-coherent light on the scale of a solar power collector, there is no net effect from interference. The increase in light intensity is not additive interference at all, but is simply that the light falling on a wide area is collected and focussed on a small area. However, I'm guessing that there is some confusion ...

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Let's suppose the light from the Sun was perfectly coherent. In that case you would get interference, however the optics used in the sort of solar tower you show are manufactured to nowhere near single wavelength of light precision. That means the phase of the light arriving at the collector would vary wildly with position across the collector, and the ...

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Though it is not common to use Fresnel lenses for electricity generation but 100 MW power plant is nearing completion in Rajasthan state of India using linear Fresnel lens technology. So to say that this technology is not feasible for large scale use is not correct and time may come if that above mentioned power generation goes smoothly, the scene may change ...

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A typical bifacial module will transmit energy that passes through the silicon as well as the energy that passes around the edges of the cells which would otherwise be absorbed in a typical monofacial module design, around 3% of the total. Using the 20% energy transmission value quoted above, a bifacial solar module will absorb ~23% less energy than a ...

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Contrary to what we might want to believe, any kind of perpetual motion device would violate the known laws of physics. No system can create energy out of nothing, and even if an engine were 100% efficient and didn't lose anything to friction, gravity, etc, it might run forever as long as there was no draw of energy out (ie. to do useful work). As nice as it ...

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There are many ideas analogous to the water tower/turbine/pump system (minus the solar panels). One common example is a water electrolysis system which passes an electric current through water to split water molecules into hydrogen and oxygen, which is then used as a fuel in either an engine or fuel cell to produce electric power to feed the electrolysis ...

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Light gets "trapped" in an optical fiber when the light travels such that the angle of incidence when hitting the surface is low enough that the optical index change causes the light to "bend" back into the fiber. This is known as total internal reflection. Basically with larger fibers you'll get light bleeding out. Thin fibers work over long distance ...

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You're absolutely right that annual mean power is by no means a useful guide to the peak power a panel might generate. You can find places on Earth where annual mean insolation is well below $100~W/m^2$, and places where it's higher than $250~W/m^2$: but at both those places, there will be times when peak insolation is $1000~W/m^2$ or more. And so all PV is ...

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Let's look at the amount of energy (in Joules) in one second - i.e. in SI units of power, Watts: that way, you can directly compare between them, and scale up the times as you choose. So, for Wh, kWh, MWh, etc - it's each of the activities below, for one hour 2 W average power used in charging a mobile (cell) phone 20 W laptop power consumption, at low ...

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