Coal is the most widely used energy source for base load electricity generation. Natural Gas is being used to replace some of the older coal fire generating power plants that are too expensive to upgrade to the current EPA regulations to minimize CO2 emissions. Burning natural gas as a replacement for coal is estimated to be half the CO2 emissions released into the atmosphere then coal. When you combine the fact that natural gas is twice the energy density of coal and half the amount of released CO2 emissions, it would be obvious that burning natural gas would be more efficient than continuing to use coal for generating base load electricity for the national power grid. Well, yes and no!
There are several different types of energy stored in materials, and it takes a particular reaction to release each type of energy. These types of reactions are: nuclear, chemical, electrochemical, and electrical. Nuclear reactions are used to generate heat for electricity in reactor devices. Chemical reactions are used by animals (that’s us) to derive energy from food or by automobiles to derive energy from gasoline. Electrochemical reactions in batteries are used by most mobile devices such as laptop computers and cell phones. And lastly, electric reactions are used by all things electrical, which is the most common power source in the world. The energy density of each of these four different types of reactions is based on the energy fuel used. For example, uranium/thorium is 1,000,000 times more energy dense than oil, which is 2 times more energy dense than coal, which is 16 times more energy dense than a lithium-ion battery. When it comes to drawing some energy from a source, which would be the most efficient?
The most logical answer would be from the densest form of energy; uranium or thorium. Back in the 1950’s, that is exactly what the chemist and physicist believed and started to develop many different reactor designs (the engines) in our National Labs and it looked like the world was going to shift its electricity generating paradigm from fossil fuels to nuclear power.
However, nuclear power stirs up some powerful emotions in people, either because of fear or misunderstanding (or both) based on how it was introduced to the general public as a war weapon. However, there’s no getting around the fact that nuclear power is the absolute safest form of power generation in operation today, the most reliable low-carbon base load power generation source, and still not reaching its maximum potential. But if it’s ever going to approach its full potential we’ll have to address the most pressing issue with the technology: used fuel storage (aka: waste).
The issue of nuclear waste has already been technically solved and demonstrable at the Idaho National Labs. They have developed a reactor that eats radioactive materials for lunch and produces heat and electricity from it. All the nuclear waste at our 100 active and 5 shuttered commercial nuclear power plants can be consumed by this type of reactor and long term storage of waste would not be needed. I support this particular design because it is the closes we have to commercialization today and is needed to address the waste problem.
However, my preferred advanced nuclear reactors are the liquid fuel designs that use either uranium or thorium energy sources. These liquid fuel designs were actually the preferred commercial design back in the 60’s but for political and government budgetary reasons, they never made it to market. This was a huge mistake and hopefully it can be rectified some day because they are even safer, cleaner and more efficient than today’s commercial nuclear power plants. So, for 2015, will it be ‘Peace on earTh’ (thorium-90) or another lump of coal?