Introduction

We use energy for everything we do. If you do science at school, you might have already learned a lot about energy and its uses. If don't know a joule from a watt, think about:

 

 

These are all simple examples of how energy is used on a small scale. Looking at the use of energy on a bigger scale: have you ever wondered where the electricity comes from to power lights in your house?

 

Electricity is produced in a power plant, a place where the energy of a certain source is converted to electrical energy (A.K.A electricity). The exact conversion process differs from power plant to power plant, but in simple terms, heat is usually used to boil water and produce moving steam, which turns a turbine. Oil, coal and gas (commonly called 'fossil fuels') are examples of energy sources used to produce the heat to boil the water.

 

Unfortunately, there's a side effect to many uses of energy, but especially when producing electricity: pollution. Pollution exists in many forms, with air and water pollution being some of the well-known types.

 

So, the sky is covered by a gray cloud and the water smells. Why should we worry?

 

 

As you might have guessed, pollution is unhealthy - very unhealthy. Because of the high amount of toxic gasses in the air, people living in polluted cities often have problems with breathing, experience coughing fits, or, in a worst case scenario, die of continuous exposure to toxic gasses.

 

Apart from the health effects, pollution is also very bad for our beloved earth. High levels of polluting gasses have caused a hole in the ozone layer in the past and are indirectly responsible for the greenhouse effect. The greenhouse effect is the phenomena where sunrays enter the earth's atmosphere, but are unable to leave again because of a layer of gasses (produced by pollution) that block it. This means that the heat is trapped inside the earth's atmosphere. As you can imagine, this leads to a rise in the temperature inside the earth's atmosphere, which in short, isn't good.

 

Using energy, especially electricity, is woven into our lives. It would be unrealistic to stop using electricity, but we can and should make sure that we don't pollute when generating electricity. We shouldn't, however, only focus on electricity - a lot of pollution comes from transport as well. In the next few sections, you'll get introduced to some of the most important/viable green energy sources. If we start using these sources instead of fossil fuels, our future looks a lot brighter.