How energy company innovation can minimise greenhouse gas emissions

Like other EU countries, Germany agreed in December that it would seek to reduce greenhouse gas emissions by 55% compared to 1990 by 2030. In addition, a 30% reduction in greenhouse gas emissions compared to 2005 was agreed in the sectors not covered by the EU Emissions Trading System (EU ETS). In order to achieve these goals, further concrete measures are required outside of the system of emissions certificate trading and emissions allocation to curb the greenhouse gas emissions often associated with energy production.

The energy industry is proportionally the largest emitter in the sectors not covered by the EU ETS, with 217 million tonnes of greenhouse gas emissions in Germany in 2020 alone. More than two-thirds of these are attributable to coal-fired power plants. By 2030, this figure would have to fall to 175-181 million tonnes in order to achieve the climate targets.

The German government and the EU want to achieve this by increasing the share of electricity generated from renewable sources such as wind and the sun, and by reducing the demand for electricity through energy efficiency. To this end, the EU Commission wants, among other things, to increase electricity generation at sea five-fold over the next 10 years. For the success of the energy transition towards climate-neutral renewable electricity, it will be crucial to optimise and expand electricity grids and to further develop so-called sector coupling, which means the interconnection of the demand sectors among each other as well as with the generation sector.

In addition, greenhouse gases are also to be reduced through the development of a hydrogen economy. According to the German government, the use of hydrogen will help the energy transition and achieve greenhouse gas neutrality in Germany by 2050. When burned, hydrogen produces almost no exhaust gases. Some experts therefore consider hydrogen-based technologies to be the key to greater climate protection.

However, large amounts of electricity are needed to produce hydrogen and to use it as an energy carrier. Hydrogen production at sea could solve this problem. In June 2020, the German government adopted its National Hydrogen Strategy and announced that Germany wants to take the lead internationally in the research and development of hydrogen technologies.

Another important step towards climate neutrality is the development of negative emission technologies - these are intended to filter out, store and reconvert the CO2 that enters the atmosphere.

One such technology is the capture, use and storage of CO2 (CCUS). There are two approaches to this: One captures CO2 in a special filter material, which is then heated and used in industrial production, with the remaining CO2-free air returned to the atmosphere; in the other method CO2 is mixed with water and pumped deep into the earth, where it is converted into carbonate. So far, however, only a few tonnes of CO2 per year can be filtered out of the atmosphere with these very energy-intensive and expensive technologies.

Similar problems arise with the technique of 'accelerated weathering'. Certain rocks like basalt and dunite bind CO2 when they weather. Close to five billion tonnes of carbon dioxide per year could be bound with basalt rock, according to a study by the Potsdam Institute for Climate Impact Research and the University of Hamburg. However, this requires a large amount of crushed rock to be scattered around the earth. Because of this aspect, this technology is also likely to play only a minor role in CO2 filtering.

In addition, afforestation is a natural means of filtering CO2 from the atmosphere. However, the land needed for this is already a scarce commodity. In addition, trees release large amounts of CO2 back into the air when they are burnt or when they rot, accordingly afforestation is only of limited use as a CO2 filter and storage medium. Fertilising the so-called phytoplankton - small algae in the sea - and stimulating their growth is also a natural way to neutralise CO2, because these algae sink into the depths after they die and the bound carbon dioxide does not return to the atmosphere as quickly.

Although one negative emission technology alone is unlikely to be able to filter the necessary quantities of CO2 from the atmosphere to achieve the climate targets set, a combination of the various measures may help to achieve the desired goal. 

This article is part of a series on international emissions trading and the newly introduced national emissions trading in Germany.