Fossil fuels are a finite resource that has enabled the development and sustenance of modern society as we know it. However, their massive exploitation has led to the current situation where, as we all know, within a not-too-distant period, we will exhaust the available oil reserves.
What we could call the oil era peaked in 1970. At that time, for every barrel of oil (its energy equivalent) invested, 200 barrels of oil were obtained. Currently, this figure has dropped to 20 barrels of oil for every barrel used. In the near future, this number is expected to decrease even further, to 5 barrels per barrel used, the point at which oil exploitation will begin to reach its profitability limit.
At that moment, as we say, very close, it will become necessary to seek new energy sources globally to maintain current energy demands. If we want to establish a truly sustainable society, it is inevitable that these new sources be renewable and their exploitation be as environmentally friendly as possible. However, the first analysis to be made is, obviously, the energy capacity these sources have in relation to global energy demand, in order to determine the real viability of the different alternatives.
Below is a list of the main energy sources, with the maximum amount of energy that can be obtained from their exploitation:
- Nuclear energy: 0.15 times global demand.
- Hydraulic energy: 0.33 times global demand.
- Geothermal energy: 5 times global demand.
- Wind energy: 20 times global demand.
- Solar energy: 4000 times global demand.
It is clear that change is possible through a combination of available technologies. However, humanity is not doing its homework. Estimates indicate that to change society to a sustainable model before fossil fuel reserves run out, it would be necessary to build 149 square meters of solar power plants every second, 1 large wind generator every 3 minutes, and 1 nuclear power plant every week. All these values are far from reality.
The situation worsens if we consider the increase in global consumption. While there is a trend towards reducing population growth, the increase in per capita energy consumption is experiencing a much greater rise. Of China’s total population, more than 1 billion people, only 20% are considered middle class. It is estimated that in the next 10 years, this figure will increase to 40%. Meanwhile, in India, with a population of 600 million (twice that of the USA), 40% will reach the middle class within 15 years.
Humanity faces a challenge of enormous proportions, led by the USA, China, and Spain, as the main investors in renewable energy. A sustainable future inevitably depends on improving energy efficiency and the intelligent use of renewable energy sources.
