Whether for heating in winter, cooking at noon or lighting at night: we need energy for almost all areas of life. If this energy comes from fossil fuels that contain carbon, it damages the climate and health. The use of renewable energies, which is on the rise worldwide as a result of the transformation in the energy system, shows that there is another way. But is the contribution to fighting climate change enough?
When we talk about renewable energies, we mean clean, sustainable sources such as solar, wind and hydropower or biomass. The terminology makes it clear that – unlike fossil energy sources such as oil or coal – these are almost infinitely available resources. And unlike fossil fuels, they do not release any substances during their use that are harmful to humans, animals or nature. The situation with biomass such as wood, rapeseed or maize is somewhat more nuanced: if burned, it produces CO2, but only as much as the plants absorbed while they were growing. This is known as a closed CO2 cycle.
According to the World Health Organization (WHO), pollutants produced by burning fossil fuels are the main cause of increasing air pollution, the health effects of which kill 7 million people every year. The UN is also sounding the alarm: 3 of the 7.7 billion people still depend on dirty energy sources for cooking and heating. The excessive use of these fuels is also accelerating climate change. It accounts for around 60 percent of global greenhouse gas emissions. The global transformation of the energy system is therefore also helping to solve one of mankind's biggest problems at present.
But how much transformation is needed to withstand climate change? And what contribution can renewable energies bring? According to the Intergovernmental Panel on Climate Change (IPCC), global warming must be limited to 1.5 degrees Celsius above pre-industrial age levels. To achieve this goal, global CO2 emissions would have to be reduced by 45 percent by 2030. And no more CO2 emitted in 2050. The expansion of renewable energies will play a decisive role in this, but not the only one. The International Renewable Energy Agency (IRENA) assumes that a combination of renewable energies, energy efficiency and further electrification of the energy supply can reduce over 90 percent of energy-related CO2 emissions. To achieve this, solar, wind, biomass and the like would have to cover at least two thirds of the world's energy supply by 2050. A glance at electricity generation shows that more effort is needed to achieve this. In this segment, IRENA calculated that the share of renewable energies needs to rise from around 25 percent in 2017 to 86 percent in 2050.
More than four fifths of the world's energy production is still based on coal, oil and gas. And the growing hunger for energy is also causing energy-related emissions to rise further: according to the International Energy Agency (IEA), emissions rose by around 1.5 percent between 2015 and 2016 to a new record high of 32 billion tonnes. However, some countries such as the USA, Great Britain and Mexico were able to reduce their CO2 emissions by switching to renewable energies.
Figures from Germany illustrate that the energy system transformation and climate protection are cross-sector challenges: for example, in Germany 37.8 percent of greenhouse gas emissions come from the energy sector, followed by the industrial and transport sectors with 20 and 18 percent of total emissions respectively. The potential to cut down on climate-damaging greenhouse gases is directly related to the levels of CO2 emissions in the respective sectors. And the increased use of renewable energies, as well as efforts by the sectors to increase energy efficiency, are helping here. A few numbers: compared to 1990, the energy industry has reduced greenhouse gas emissions by 33 percent to 311 million tonnes of CO2 equivalent in 2018. In industry, CO2 emissions fell by 31 percent over the same period. The construction and agriculture sectors have also been able to improve their climate balance. Only in the mobility sector have greenhouse gas emissions remained virtually unchanged. The potential in this country for climate protection is correspondingly high if sustainable solutions for transport take hold. For households, in addition to renewable energies climate protection is being driven by greater efficiency in the supply of electricity and heat in particular.
There is still a considerable difference between 'is' and 'should be' when it comes to climate protection. But this also shows that renewable energies are being expanded further overall and are making a significant contribution to reducing climate-damaging gases. This not only benefits climate protection. The change from dirty energy sources to clean energies also promotes the economy, development and health. However, integrating solar, wind and hydropower into our lives as energy sources remains a global challenge – and a joint task of entire states, municipalities, companies and private individuals.
