Solar: 170,000 terawatts. Tidal: 3.5 TW. Biomass: 150 TW. Wind: 500 TW. These numbers matter. They tell a story of available renewable energy, of energy that could be harvested continuously. There are two more numbers just as, if not more important: 15 TW, which is the current global consumption of energy, and 110 TW, which is the projected global consumption of energy if the entire world could satisfy its energy needs. Evidently, we have the renewable resources to cover these needs. 170,000 terawatts of solar energy alone can sustain a world 100 times more energy intensive than projected.
Problems arise, however, when you look at the finer details. While it is tempting to make sweeping statements about the benefits and universality of renewable energy, logistics must be met. In a lecture on alternative energy resources, Professor David Walker outlined five key points that an energy source must meet to be viable: first and foremost, it must be large enough to meet the demand. It must also be practical to harvest, both technically and economically. Further, it should be in sync with fluctuating demand, both daily and seasonal. Last but not least, it must be environmentally acceptable.
Over the past two hundred years, we have developed a reliance on fossil fuels to serve our energy consumption requirements. This is not a surprise. It would take 10,000 gallons of falling water to equal the amount of energy concentrated in one fiftieth of a gallon of oil. Fossil fuels are extremely proficient at their job: they provide reliable power whenever and wherever it is needed. The sun might not shine, the wind might not blow, but coal will always burn, natural gas will always combust.
Fossil fuels are also abundant. Fears of running out, of peak oil, or peak coal, or peak gas are unfounded. The United States alone has nearly half a trillion tons of demonstrated coal reserves, enough to power the country for hundreds of years. This is assuming, of course, that efficiency standards remain the same.
Improvements occur all the time, and our fossil fuel reserves can be stretched far more than projected at the present. Of course, the use of fossil fuels does not come without its consequences. Carbon emissions, coupled with pollution, might cause irreversible damage to our planet’s climate. There are other byproducts from burning fossil fuels besides the obvious greenhouse gas emissions. Waste products from coal burning, for example, contain a great deal of toxic substances such as mercury, uranium, and lead. Just like any other energy source, more care is required to ensure safety.
In nearly all cases, renewable energy sources don’t meet the five conditions outlined earlier. Solar energy, abundant in many areas of the world, is not prevalent during times of greatest need, such as for heat during the Northern and Southern winters. Solar panel production is also notoriously detrimental to the environment. Wind energy has a similar problem in terms of reliability. Harnessing too much wind, interestingly, may cause changes in atmospheric circulation, leading to unknown climatic consequences. This, however, is a very new area of study that is constantly changing. Biomass is an interesting case. It can be used as needed, and therefore provides the same reliability as fossil fuels. However, the use of biomass cuts into food production, which, for a growing human population, might lead to disastrous consequences.
Fossil fuels are therefore necessary to our continued growth. They provide stability and performance where they are needed. We cannot live in a world where the well- being of humanity must be sacrificed. We cannot hinder our development. There is no question that technological improvements in efficiency must be made, and that better techniques for extracting and burning fossil fuels must be found. There must also be no question that they serve a vital purpose in our society and should continue to do so.