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Natural processes are notoriously inefficient
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The scale and the value make all the difference
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The energy balance explanation for anything and everything
The direct utilization of sunshine by plants for food, fiber, fuel is supported by a capture and conversion
efficiency of a fraction of 1%.
The reason that is ok, is because plants operate mostly unattended, and that translates into an economical and
affordable harvest of energy. Some refer to it as dirt-cheap.
The other 99.9% of the sunshine the plants don't use goes into the atmosphere split between the warmth of the
air and the latent heat of vaporization of the water the plant took in. Those inputs of energy drive the
wind and the rain.
We use technology to capture solar energy directly. We apply Thermal-Capture when sunlight is absorbed
by an any object, it is a physical process, and can capture almost 100% of the sunshine as heat. PV is a
quantum process relying on pure or exotic materials and captures up to 20% of the sunshine into a directly
usable form. The other 80% is lost as unusable heat.
Solar-Thermal is what happens That heat can then be converted to a more useful form (electricity) with
efficiencies from 15-40%. Of the remaining heat, as much as 30% is still usable for other purposes.
Summary
Agriculture is efficient at capturing solar energy, plants capture only a tiny fraction of a percent, but do
it very inexpensively.
PV might bring 10-15% of the energy to market, but the capital cost is staggering.
Solar-Thermal, utilizing Organic Rankine Cycle technology, can harness
20-30% of the energy in sunlight to market, at a capital cost approximately 1/3rd of PV.
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