Renewable energy has been a hot topic for 2019, as countries around the globe attempt to decrease their reliance on coal and oil and move towards other, more environmentally friendly options. The year ends with world leaders gathering at COP25 – the UN’s climate change conference – where decisions will be made about how to fully implement the Paris Agreement. This agreement aims to limit the global temperature increase to 1.5 degrees, and the use of renewable energy sources will be a huge part of helping to make this happen. In 2019, use of renewable energy has rocketed. But what are the best renewable energy sources of 2019?

What is renewable energy?

Renewable energy is power generated from natural sources which are constantly being replenished, such as sunlight, wind and flowing water. Renewable energy will never run out. These sources are often called ‘alternative energy’, because they are an alternative to traditional fossil fuels. 

It is easy to think that renewable energy is environmentally friendly. Though they tend to be far less polluting and damaging than fossil fuels, there is a hierarchy. Some renewable energy sources produce just as much air pollution as fossil fuels! Others, however, are very clean and will be the future for green energy production.

What are the best renewable energy sources of 2019?

As our science improves, and our methods of producing energy get more efficient, we will be able to harness more and more sources of renewable energy. In the UK, just four coal plants remain as the switch to renewable energy ramps up. Different countries favour different renewable energy sources. Here are the best ones:

Wind

Top of the list of the best renewable energy sources of 2019 is wind power. Wind is the UK’s strongest source of renewable energy, and makes up 20% of all of the electricity generation in the country. The world’s largest offshore windfarm, the Hornsea One project, is situated off the Yorkshire coast and more windfarms are planned over the coming years. In fact, the Labour party plans for a Green Industrial Revolution – this would bring 37 giant new offshore windfarms. Wind power is clean; it does not produce air pollution and is truly renewable – wind won’t go away! Worldwide, wind power is the second most widely used renewable energy source and is growing at a rate of 25% per year – making it the fastest growing renewable energy source too.

However, there are some negatives. Whilst the energy production process is not polluting, the actual manufacturing process – building the turbines – is. In addition, windfarms can be damaging to wildlife. Turbines are responsible for over 500,000 bird deaths.

Hydropower

Hydropower is the most widely-used renewable power source worldwide. It accounts for over 16% of the world’s electricity production and over 65% of the world’s renewable energy use. This is largely led by China, which has the largest hydropower plant and accounts for over 50% of the worldwide hydroelectric power. Other large countries such as the United States, Canada and Russia also utilise hydropower. Hydropower harnesses the power of water falling to turn turbines, and as such is clean and highly renewable.

Are there any issues? Well, the amount of land required for the huge dams is extensive, and the building process can cause environmental damage and human resettlement problems.

Solar power

We’ve all heard of solar power – harnessing the sun’s heat and light to produce energy.  It features surprisingly highly on the list of the world’s most used renewable energy sources (especially given the climate of many countries successfully using it!). In the UK, for example, solar power is the third highest source of renewable energy production. You might not know that solar power doesn’t actually require direct sunlight – daylight is enough to produce some energy. Solar power is popular for individuals as well as energy suppliers. The addition of solar panels to a property can not only get rid of energy bills but also provide more to energy to the national grid.

Unfortunately, solar farms are expensive and unreliable – on overcast days or during the winter, they will produce less energy than they would on a bright, sunny day.

Bioenergy

Bioenergy is a fast growing energy source. It is the second most used renewable energy source in the UK and the fourth most used worldwide. Bioenergy harnesses the energy found in plants and other living things; this might be by burning wood pellets or extracting gas from farming byproducts. This can be carbon neutral if the source – the plants or trees – is constantly replenished. Bioenergy is easy to produce. Often, existing coal-fired power plants can be simply converted into bioenergy plants.

However, some bioenergy processes (for example, burning) release damaging pollutants into the atmosphere. This makes it a less environmentally friendly option than other renewable energy sources.

Geothermal power

Geothermal power harnesses the earth’s internal heat. Drills are used to tap into the underground reservoirs of steam and hot water, which can be used to heat homes and generate electricity. Some countries are better suited to geothermal power – for example, Iceland, which sits over a rift in continental plates and has a high concentration of volcanoes, is one of the world’s largest users of geothermal power. In fact, fossil fuels make up just 0.1% of Iceland’s energy generation! 

Of course, as geographical location is important, it is utilised less in some countries than others. However, in the UK there is a large heat resource potentially available underground which is largely untapped. Significantly more funding would be needed to extend this source of power here.

Which renewable energy sources will increase next year?

In order to meet the requirements of the Paris Agreement, the UK will need to see 75% of its electricity generation coming from renewable energy sources by 2030. Much of this will come from wind power, as all political parties pledge an increase in windfarms over the coming years. Bioenergy is also likely to increase, as plants such as the Drax Power Plant in Yorkshire investigate ways to make this power source less polluting. Whatever the source, 2020 will see significantly more renewable energy sources being used, with more than 30% of our electricity coming from renewable sources by the end of the year.