In terms of the world, the current energy portfolio to meet the global demand for energy is shown below [38].
Also, nuclear energy is not widely used in the world with only 6.30 percent energy generation from this energy source. Biomass as an energy source is more commonly accepted worldwide (10 percent) than in the United States (only 1 percent). This can largely be attributed to the large-scale burning of wood in third-world countries to meet their cooking demands.
Lastly, it is important to note that only 0.50 percent of all energy production in the world comes from the renewable sources geothermal, solar, and wind.
As with the United States, the current worldwide portfolio will definitely not be able to last for the same reasons as why the United States' energy portfolio will gradually have to transform.
For one, the fossil fuels that are used in high excess to meet the global energy demand will all run out. Projections of when these fossil fuels will run out is a relatively unknown answer. However, it can be generously said that if the current portfolio does not change, natural gas will run out in 60 years, oil will run out in less than 100 years, and the coal reserves will run out in less than 125 years.
Secondly, the high content of GHG's released from fossil fuel energy production creates hazardous and life-threatening issues. The level of carbon dioxide has already reached unprecedented levels and could cause many illnesses if the problem goes unattended. Next, there is a high probability that as the GHG concentration in the atmosphere rises, the sea level will rise. Land that was once prosperous could be underwater in the next 200 years.
The final drastic effect that fossil fuels create is the energy dependence on one another, creating wars and economic downturns for several countries. Since oil, coal, and natural gas are only in specific locations, fluctuations in prices causes volatile economic times with a strong dependence on these energy sources. Especially as the fossil fuel sources are running out, the prices will become more and more volatile, creating more hostility and violence between nations.
With the effects of fossil fuels emphasized, the most common sense solution is to transform the world energy economy from a fossil fuel-based one to a renewable energy-based economy (geothermal, wind, solar). However, as can be seen on the figure above, only 0.50 percent of the world's energy stems from these three renewable energy sources.
The answer seems simple and solves all of the problems that arise from fossil fuel energy production. However, it is one of the most complex problems that the world faces today. What's stopping this transformation?
One of the leading forces in stopping this transformation is a lack of political will. Until governments not only locally but worldwide get on the same page and get committed to spending significant amounts of money to build renewable energy infrastructure, the current energy portfolio will not change much. In other worlds, this has to be a large-scale energy transformation.
Also, efficiency of the renewable sources have to be improved. For example, solar energy on average only has an efficiency of 15 percent.
Lastly, the building of capital for these renewable energy industries is too much money right now for large-scale adaptation. However, as the industries gain popularity and sell more, the prices will drop severely.
