Oil well at sunset
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Energy sources of the future.


Fossil fuels (oil, coal and gas) are rapidly running out, and those resources which are left are in harder and harder to reach places. Resulting in higher prices and a possible future energy crisis. In order to prevent this the world must utilise alternative sources of energy, in this article I attempt to summarise what I think are the top ten energy sources we could use in the future. To be on my list it must have substantial room for further development and it must be capable of providing the world with energy until at least 2050.



10.        Osmotic power

Is about collecting energy from the difference in the salt concentration between seawater and river water. There are test plants using this technology in Sweden and Norway, however this technology requires strong and cheap membranes which aren't currently feasible and may never be) in order to compete with other energy sources. It may also be environmentally damaging to estuaries.


9.     Ocean Thermal Energy Conversion

Collects energy from the difference between warmer and colder oceanic water. This method may eventually be commercially viable as a lot of energy can be produced, however it is in the early stages and technical issues are still being addressed.


8.         Wave power

Wave power is the extraction of energy from waves. Waves are created by wind, however they gather wind energy from a large area making them less variable than locally sourced wind power. Wave power is new and developing rapidly so it needs more time before it becomes commercially viable. However even if it does the technology is limited by the length of coastlines facing large bodies of water.


7.         Tidal Power

Tidal power is the extraction of energy from tides. It is a current source of power where there is potential for growth.  Tidal power plants have existed since the 1960's but they are becoming cost effective in a larger number of locations due to improvements in the control of water flow and in turbine design. Viable but limited by the number of appropriate locations.


6.         Geothermal power

Geothermal power is the extraction of energy from the hot mantle of the earth. This method could conceivably provide all of our power supplies for several thousand years, however it relies on drilling through the earth crust and has therefore only been economical in places where the crust is thin such as in areas where there is volcanic activity. 


5.         Wind power

Wind power Is currently a popular technology because in windy areas it produces enough power to make it close to cost competitive to fossil fuels. However this technology has two problems which will probably prevent it becoming a major source of energy in the future, these are intermittency and that it is hard to increase wind turbine efficiency further. The intermittency problem is caused because it is very difficult to predict when it will be windy. Unless efficient ways are found to reduce the effects of this intermittency wind will likely only be useful in regions with more consistent levels of wind like Scotland.


4.         Fusion power


Fusion power collects energy released from the fusion of two atoms. The advantage of fusion is that it would provide us with sufficient energy to power the world  virtually indefinitely because a  potential fuel is an isotope(variant) of hydrogen known as deuterium. This isotope is present in abundant amounts in seawater and the energy that it provides would be sufficient to power the world for billions of years with almost no dangerous radiation.


The problem with fusion at the current time is that no-one actually knows if its possible to control it in a nuclear reactor in an efficient enough method to create energy. Because of this fusion is perpetually '50 years away' and although progress is being made there is still too many question marks about the technology for it to be a sure thing in the future. This reduces investment in the technology and therefore slows the rate of progress even more, however one day this century it may be possible to use fusion energy to power your home.


3.         Reprocessing nuclear waste

Another source of energy which is significantly underdeveloped is nuclear waste. Nuclear waste in the form of depleted uranium and plutonium can also be used to provide energy. This has great advantages particularly if the nuclear waste is used in a breeder reactor which eliminates all of the radioactive products of fission, the energy in current nuclear waste could last thousands of years. However breeder reactors have not been pursued because reprocessing is expensive and more easily produces weapons grade plutonium encouraging nuclear proliferation.


2.             Solar Power

Solar power has been considered the energy of the future for a long time but is only over the last couple of years with the rapidly reducing cost of solar cells that it has become a viable energy source. Solar in some parts of the world  has reached a point known as parity. This means it costs a similar amount to buy energy from solar sources as it does from other sources (mostly fossil fuels or traditional nuclear). The price of solar cells is expected to fall further as production is ramped up and thinner and cheaper solar cells are used, expanding the number of areas where it has become as cheap or cheaper than other sources. However it is unlikely it will ever be able to provide the majority of the electricity in temperate regions. A great thing about solar is that it can make idle space like that of a roof into a way to generate energy. It is also efficient because it means people can use their own energy without the need for wasteful power-lines.

 1.         Thorium.

Thorium is an obscure radioactive element which is currently becoming more and more prominent because of its possible use as an energy source of the future. So how could thorium provide us with energy in the future?

 Thorium is a radioactive element that can be used as a fuel of nuclear fission in a similar way to uranium. However uranium has several problems which thorium doesn't have. Uranium reserves as a finite resource are running out quite quickly in a similar way to oil reserves, for this reason they may not last until 2050(assuming no reprocessing). Thorium is more abundant, a larger amount of the world’s thorium supplies can be used to create energy. Less nuclear waste is produced and thorium reactors can be turned off at the touch of a button.  For all these reasons thorium is the best energy for the future.

Credit: US Government