There are many ways to generate electricity more sustainably. Fossil fuels, which include oil, gas and coal, form underground from the remains of animals and plants. For the past 150 years, humans have been burning these fuels to produce electricity. However, fossil fuels are a non-renewable source of energy, which means that someday they will run out. Some fossil fuels may even run out in our lifetime. In addition, fossil fuels release greenhouse gasses such as carbon dioxide, which trap heat in the Earth’s atmosphere. The resulting increase in temperature is known as global warming, and Earth is currently heating up at a dangerously fast rate. In the next 100 years, atmospheric temperatures could increase by 1.4°C to 5.8°C. The effects of this climate change include habitat loss, sea levels rising and extreme weather patterns.
Luckily, countries have begun using renewable energy sources to produce electricity. As well as not releasing harmful greenhouse gasses, renewable sources of energy never run out! Globally, the three primary sources of renewable energy are hydropower, wind and solar power. Firstly, hydropower generates energy from the movement of water. Water rises behind a dam opposite a river valley and then moves through tubes inside the dam. This powers electrical generators, which allows electricity to be produced. Wave machines also use the movement of seawater on a shore to drive turbines, while tidal barrages use movement from tides. Wind turbines, which consist of blades on a tower, are another way to sustainably generate electricity. The moving wind pushes the blades around, which turns the generator. Often, many wind turbines are built together, which creates a wind farm. The third largest renewable energy source is solar power, which is harnessing energy released by the Sun. Solar panels capture energy from the Sun and turn it to electricity, and a more simple set up uses solar power to heat water.
Other renewable energy sources include biomass and geothermal energy. Biomass energy is energy produced through burning decaying waste or organic material. Meanwhile, geothermal energy is produced using the Earth’s internal heat. In volcanic areas of the Earth, rocks heat water that rises to the surface as steam. When steam does not naturally rise to the surface, wells can be used to pump cold water down to the rocks, which later rises as steam and hot water. The energy from this steam can be used to power turbines and electricity generators.
While using renewable energy sources is better for the environment, there are still some limitations. Renewable energy sources are often expensive to make and can not produce as much energy as fossil fuels can. Often, the effectiveness of a renewable energy source depends on its surrounding environment. Wind turbines can only generate electricity when there is wind, hydropower can not work without water sources and geothermal energy produces much more energy in volcanic areas. This means that the amount of energy generated by renewable sources often changes and is not as consistent as energy from fossil fuels. Renewable energy sources can also harm the surrounding environment. Wind turbines can be dangerous for flying birds and bats, while hydroelectricity dams can harm the surrounding landscape. These dams can cause flooding, displacement of nearby residents and disruption of river ecosystems. Lastly, although these renewable energy sources do not release as many atmospheric pollutants as fossil fuels, they still sometimes give off pollutants. Biomass releases some pollutants, including greenhouse gasses, when it is burned. Methane, which is a greenhouse gas, can be released from decomposing organic material in hydropower reservoirs. More research and funding will allow for the improvement of renewable energy sources, as well as the discovery of new sources.
Despite the disadvantages, many countries use renewable energy sources because of their positive effect on the environment. By 2015, hydropower generated 16 percent of the world’s electricity, and other renewable sources generated another 6 percent. Specifically to the UK, for the first time ever, more renewable energy was generated than fossil fuels in 2020! In particular, the UK has been extremely successful in generating wind power. The UK has more than 11,000 wind turbines! Overall, renewable energy is an important part of reducing greenhouse gas emissions and preventing further climate change.