Why Every Dog Should Love Quantum Physics 2: Solar Panels

Yesterday's reason to love quantum was the CCD sensor, which relies on the photoelectric effect to take digital pictures. Sticking with the photoelectric theme, today's first quantum-enabled technology is the photovoltaic cell, the basis for solar panels.

Photovoltaic cells convert light into electricity, essentially via the same photoelectric effect used in CCD's. A photon of light comes along, and knocks an electron out of some material (typically something silicon-based), and that electron is used to create a current that can power electrical devices. There's some tricky business involved in setting things up so those electrons can be made useful, but the essential physics is just the good old photoelectric effect explained by Einstein in 1905.

Typical photovoltaic cells have very low efficiency, and there's a ton of research going on these days into ways to make higher-efficiency solar cells. Much of this work involves small improvements to the basic silicon structure, but all sorts of exotic things are in play. There's a group at Union looking at the possibility of using "quantum dots" mixed with long polymers as an alternative photovoltaic material, for example.

Why is this important? Well, solar cells can be used for lots of cool things, from powering satellites to beaming power to a space elevator. The main application, though, is for electricity generation, as a replacement for coal or gas power plants. Solar power is the ultimate in "Green" energy-- it produces no carbon dioxide or other pollution, and won't run out for billions of years, until the Sun stops shining.

Why should a dog care about it, though? Two reasons:

First, any dog who enjoys chasing critters (and what dog doesn't?) should be in favor of lowering pollution. Less pollution means that all sorts of chaseable critters will have a better chance of surviving. That means a greater diversity of things to chase, and some of them may even be useful to humans.

Second, higher-efficiency solar panels could help reduce the cost of electricity for humans, both in the direct cost of fuel, and also through reduced dependence on oil and gas, which tend to be concentrated in unpleasant places full of crazy humans (the Middle East, the North Sea, Texas, etc.). If we cut down on the amount of oil and gas we use, that means that humans will have more money to spend on the really important things in life, like dog treats and squeaky toys.

So, dogs should definitely be interested in solar power, and that, in turn, means that dogs should be interested in quantum physics. If we didn't understand quantum physics, we wouldn't be able to make solar panels, or make better solar panels for the energy needs of tomorrow.

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