Worlds demand for fossil fuels
Social and economic development has brought an age of high energy consumption and demand. Over the last two hundred years energy consumption in the four economic sectors (residential & commercial, industrial, transportation and electric power) has increased globally and in the next two decades global energy use will rise significantly. Our energy use however depends in large part on fossil fuels, Despite the fact they are cause of serious environmental impact (contributing to green house gasses causing global warming), can be source of political tensions, and they are finite sources of energy. For this reasons there is investment in alternative sources of energy and renewable energy. These forms of energy include:
• Large hydro
• Solar thermal
• Solar photovoltaic
Nuclear energy is derived from uranium a radioactive metal which is mined in different parts around the world. Nuclear fission is the splitting of unstable atoms. For example if an atom of uranium is hot by a neutron it will split in two other atoms and two neutrons and releasing energy. If the process is repeated often enough it can release large amount of heat. This process occurs naturally, giving off radiation, but when it is sped up by enriching natural uranium to contain a higher proportion of U-235, in the right conditions it can become a self-sustaining chain reaction that releases immense amounts of thermal energy. The heat generated from this process is used to heat up water in the reactor, the water becomes steam, it moves turbines driving a generator and making electrical energy.
Nuclear energy is not a limitless source of energy. Current conventional thermal nuclear reactors around the world in total consume about 70.000 tons of uranium per year. Uranium is widely distributed around the world and in total we have about 3851 million tons. Which can amount for 55 years of supply, and if we consider hypothetical reserves the lifespan of uranium becomes 200 year. This doesn’t differ much from the fossil fuels: In total lifespan coal is expected 200 to 400 years for example. There are plans to develop recycling nuclear reactors: breeder reactors and depending on the rate of nuclear energy use we could need them by 2050. What breeder reactors do is improve the efficiency of the reactors, which currently stand at 2% to 75 or more and this could significantly raise the lifespan of uranium to eighty thousands of years.
Breeder plants development however present several problems: associated in creating a uranium cycle joined with a recycling cycle (including the costs involved. Demonstrations of breeder plants were constructed in France and Japan. These have proven to be very expensive compared to normal reactors- and they are due to be shutdown. The very few breeder reactors that work at present produce less energy that the closed breeder reactor projects.
An alternative solution to the problem of the life span of nuclear...