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Topic: Society
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We are very dependent on energy, even if we do not always think about it. Cooking, heating, lighting and many other things, the computer I'm writing on, for example. It is only to stop the plug into the wall to run an appliance running. But how does it work? Energy can neither be created nor destroyed, it can only be converted into olka forms. Altså we must take energy from somewhere else to get electricity, it is the conclusion I draw.

There are many different sources of energy, we can take care of, but they can be divided into two groups: renewable and non-renewable. The renewable flows constantly and can be recovered. They will never end unless the earth go under. The non-renewable sources of energy must be stored a long time and is renewed extremely slow. They will run out one day.

I have chosen to study two sources of energy, hydropower and nuclear power - a renewable and non-renewable. I start with hydropower, the somewhat simpler.

An environmentally friendly energy source

Hydropower is altså a renewable and environmentally friendly energy source. The discharge neither smoke, soot, or other hazardous waste whatsoever. It mainly affecting nature's building and expansion of hydropower. Then you have to build the dam, power plants, roads, pipelines and so on. Everything like that changes the course nature, both for humans and animals.

How does hydropower?

Hydropower is to transform the water potential energy to electrical energy. You build a pond to collect a large amount of water from a river. When the pond is full enough to allow the water to fall down on a large turbine, a kind of waterwheel. The turbine rotates and drives a generator that converts water energy into electricity. Since the voltage is transformed to about 400,000 volts to get as little loss as possible - as usual when it comes to electricity altså.

Hydropower and fishing

Hydropower is environmentally friendly, but the dam will be a one-way street for the fish. Salmon and some other fish are born, for example, in rivers and migrate to the sea. A hydroelectric dam prevents unfortunately salmon from getting back since. At mordernare hydro adopts one so-called fish ladders. In them salmon "climb" up the river, to the side of the dam. However, this is completely unnecessary at older power stations, where the salmon have already abandoned their playgrounds.


We have had hydropower for over 100 years in Sweden. Today, hydropower expanded to 64 TWh. Geographically speaking, it could be built along 130 TWh. They built the 24 TWh in the mid-90s, due to economic reasons. Today, interest has increased a lot, but Parliament has decided to protect the many rivers and river stretches. It makes it impossible to conduct any major expansion.

But hydropower is much cleaner than nuclear power, which I intend to take up now.

Waste from nuclear power

Unlike hydroelectric drop out nuclear waste, radioactive waste. If it is not taken care of properly, it can cause damage by the radioactive rays trend. It encapsulates it and keep it 500 meters into the ground. It keeps radiation away from people and the environment.

How does nuclear power?

Uranium nuclear fuel. Uranium comprises four istoper (different forms of the same element). There is uranium-233, -235, - 237 and -238. To get the heat required must be split uranium. There is uranium-235 that has great cleavage propensity. Natural uranium contains only 0.7% uranium-235, so the amount needs to be enriched by a few percent. Since uranium is ready to use.

First nuclear power plant, we have a reactor where the uranium is split, and heat is generated. Where the heated water up to 280 ° C, but the pressure is kept so high that it can not boil. The pressure is controlled via a pressure maintenance vessels. The hot water is then led into a tube through a steam generator, where steam is formed. The hot steam is passed through the tube to a steam turbine. The pressure enables the steam turbine blades rotate, at a rate of 3 000 rpm. The turbine then drives a generator that produces electricity. Then cool down the hot steam is pumped into the sea water. Havsvatnet led in many thick finger tube through a Turbine condenser, where the vapor is condensed. Then the water goes back to the steam turbine to be used again.


The future of nuclear energy looks bleak, even if it might be an advantage. One gets under Swedish law does not build new nuclear reactors. In addition, one of our major nuclear power plant, Barsebäck, to be put down. Nuclear power is simply not environmentally friendly or renewable. Nuclear power serves, however, for a lot of the energy we receive. Several countries, such as Finland invests heavily in the future of nuclear power. There comes a fifth reactor to be completed in 2009.


Now I have taken up the two largest sources of energy in Sweden today. Both have the their advantages also disadvantages. Hydropower does not affect the environment, more than expansion. It makes nuclear too. Nuclear power does not affect fishing, in the way that hydropower does. Today's hydropower've largely fish ladders, but salmon have said was already abandoned some of their old playgrounds. There is not much to make a fuss about today - done is done, and the salmon can use laxtrapporna.

Nuclear power's radioactive waste're still there today. The latest polls show that there are twice as many as want to keep and invest in nuclear power, compared with those who want to abolish it. I do not agree. Radioactive waste is very dangerous. Just wrap and bury it in the rock will not help us in the long run. I think that we should invest heavily in renewable energy and completely forget about nuclear power.

I'm not entirely agree with Parliament's decision to protect certain rivers. Maybe it's nice areas, but in the long run, nuclear power and other non-renewable energy sources to destroy them anyway! To build hydropower would rather help the elements of nature.

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