Power Conversions

Generating electrical power for use by consumers or industry is a big business.  There is a lot of applied science required in order to make it all work.  Strangely the dominant method of generating electricity is almost always by burning something to make steam, the steam turns a turbine that is attached to a generator.

Pretty simple.  Burning stuff is easy and there are a lot of different things that can be burned.  Coal, natural gas, even municipal waste.  Spent engine oil, even old used tires of which there are a lot.  Eventually it comes down to the amount of thermal energy that is stored in the material to be burned and what temperature it burns at.

Except that burning stuff doesn’t make a lot of sense.  There are a lot of complex secondary products that have to be dealt with.  Just like burning wood in a campfire or fireplace leaves ash, coal fired powerplants produce ash, but at the scale of a powerplant, it adds up to tons of ash.  So what do you do with the leftovers?  Make landfill?  On the chemistry side there are also problems with the byproducts of combustion; carbon monoxide, nitrous oxide and soot particles that can become airborne.  Over the last decades the power industry has successfully ‘cleaned up its act’ so that the negative effects of burning fuels have been minimized.   But, there are other options.

If you have a source of flowing water you can turn a wheel that turns a generator.  Even easier.  So we have hydroelectric power generation.  Unfortunately, in order to scale hydroelectric plants to useful size, large bodies of water have to be created by damming rivers.  Big changes occur in land use and sometimes whole populations have to relocate as in the case of the Three Gorges project in China.

Or there is nuclear power.  Refined radioactive materials give off huge amounts of heat.  Creating steam is easy and the stuff lasts for years.  Unfortunately these materials have so much energy that it is difficult to manage.  Water cooled reactors have been around since the first one was tested in 1952 at the Idaho National Laboratory.  The history of these types of reactors has been spotty and failures at Three Mile Island, Chernobyl and Fukushima, among others, should give us pause before any similar reactors are built.

All of which is what leads our modern civilization to look for other energy sources that can be converted to electricity.





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