Humans are ingenious and we have developed many strategies for wresting power from nuclear fission and fusion. All energy generation can be traced back to radioactive decay, whether it is the sun or unstable elements here on Earth. The most obvious and direct way we generate electricity from these reactions is through the use of nuclear power plants and photovoltaic panels. The next level of energy generation burns biomass that grew using solar radiation. This can be either ancient biomass that has been compressed into coal, gas, or oil or the combustion of recent biomass in the case of wood stoves. The third level of energy generation comes from the consumption of biomass, either through directly feeding an animal, such as an ox that pulls a plow, or burning the fermented and distilled byproducts of consumption, such as with corn ethanol and biogas. The final level comes from the atmospheric effects of solar radiation, namely the movement of air and water over the land surface, which generates power from wind, tides, and dammed rivers. In some cases, we can see a right way to harness this power, but in many instances, these resource are best left untapped because their side effects outweigh their benefits.
On the first level, the direct use of nuclear reactions, we see two diametrically opposed systems: nuclear power plants and solar energy. Nuclear power is generated when fissionable material (usually Uranium) is allowed to decompose into daughter elements. This produces heat that is transferred through a heat exchanger to water, which boils, creating steam. This steam passes through turbines that generate electricity. On the one hand, no carbon or other greenhouse gasses are emitted through this process, which is the main positive characteristic of nuclear energy. On the other hand, nuclear generation is a centralized system, and when the plant goes down for maintenance (or other reasons), it causes widespread disruption. More importantly, even when running according to design, nuclear plants generate waste that has nowhere to go. Right now, the US has well over 50,000 tons of nuclear waste waiting for a permanent repository. In addition, the chance, even though it is a small one, of a nuclear meltdown is too great a risk. The cost-benefit analysis of this energy source is decidedly in favor of shutting it down.
Photovoltaic panels, on the other hand, generate power by converting solar radiation into electricity by taking advantage of the photovoltaic effect, which is essentially when light excites an electron to produce an electric charge. Of course the manufacture, transportation, and installation of photovoltaic panels under the current system is dependent on fossil fuels, but the one-time cost of their creation is outweighed by the long-term clean, decentralized energy generation. Solar arrays, which are large installations often placed in deserts, concentrate the sun’s rays to a central point, creating steam and rotating turbines to create electricity like a conventional power plant. Although no greenhouse gasses are emitted and it does not generate dangerous waste, these are complicated and centralized systems and may not be as sustainable in the long term as a distributed grid of rooftop solar panels.