Nuclear Energy by Erik Arnesen '07

How is nuclear energy produced?
• Nuclear power is either from fission or fusion reactors, which are boiling water, pressurized heavy water, liquid metal heaters and lead cooled.
• What type of fuel is used?
The fuel used for nuclear power can be uranium, plutonium or thorium

How does it work?
• Nuclear power can produce 3.7 millions times as much energy as coal
• Nuclear fission consists of the splitting of the nucleus into two smaller nuclei creating a massive amount of energy and heat. This reaction is controlled, which boils water and produces steam which spins a turbine.
• Nuclear power accounts for 20% of US electricity. The largest percentage of reactors providing electricity is France, which has 80%.
• Present nuclear power will last us for hundreds of years and with Breeder reactors, billions of years. Breeder reactors use U-238 as a fuel instead of U-235
• Nuclear power used in fission lasts only about 18 months and must be removed and replaced by new fuel rods

What about nuclear waste?
• Most power plants produce 30 tons of spent fuel annually, which is stored on site
• What has been done in many countries and not the US is reprocessing spent fuel rods, which are used over and over again. This has been prevented by Jimmy Carter who believed that reprocessing the fuel was wrong and with the US doing away with it, others would follow. This is not the case as the rest of the world now reprocesses its spent fuel rods.

Future
There have been many new developments with nuclear reactors, making them safer and more powerful than ever before. A few of them are
• Generation IV reactors- these are the next evolution of the current Gen II and Gen III reactors, making them safer, less costly and minimize waste.
• Very High Temp reactor- uses a graphite-moderated core at a temperature of 1000 degrees Celsius. The core can either be block or pebble bed design. Pebble bed design consists of smaller pieces of uranium broken up in fuel rods that make it safer and easier to cool instead of one piece fuel rods.
• Both of these reactors use passive nuclear safety which only relies on its computer systems to regulate the behavior of its components making the reactor work. During an emergency, the reactor would slowly cool, rather than accelerate quickly, as to not prevent damage to the core reactor.
• Public opinion recently has gone more in favor of nuclear reactors, with green initiatives showing the no pollution effects with reactors.