Carbon capture for a net zero Copenhagen

Carbon capture, utilisation, and storage (CCUS) is high on the agenda as part of the solution to the world’s climate issues. Globally, there is general agreement that it will be required to meet the carbon emission reduction targets and the global warming mitigation aspirations of the Paris Agreement. In Denmark, the government has high expectations for CCUS, projecting a potential annual reduction of 4-9 million tonnes per year by 2030.

The Amager Bakke waste-to-energy facility in Copenhagen, Denmark has reached a key milestone by implementing a demonstration plant, the first of its kind in Denmark, capable of capturing 4000 kg of CO₂ per day. The primary purpose of the plant was initially to test carbon capture technologies and optimise the energy integration with the district heating network.

Currently, the demonstration plant captures the CO₂ which is then transported in liquid form to Østervang on the Danish island of Zealand for growing vegetables. This is an example of successful value chain integration for capturing and utilising CO₂.

The Energy Technology Development and Demonstration Program (EUDP) supports the project with DKK 30 million, and the remaining DKK 30 million are funded by ARC, and the partners, including Ramboll.

Ramboll's responsibility on the project is to test a plant design that produces as much energy with carbon capture technology as it does without it, ensuring the plant's operations adhere to net zero energy goals. This has been technically challenging and has required Ramboll to develop new concepts in joint effort with ARC and the suppliers, resulting a 30 percent reduction of the energy consumption for the carbon capture process. Thus, through this project, Ramboll has gained several new competencies as well as tools for optimising carbon capture plants and their integration with the CO₂ source facilities.

Ramboll has also supported ARC with technical inputs to several aspects including design, permitting, and tendering support for the full-scale carbon capture plant.

Research, development and pilot projects such as these pave the way for commercial use of the technology and may ultimately result in the waste sector not only eliminating its own CO₂ emissions but also contributing to negative emissions. These new technologies have the potential of redefining the function of waste-to-energy facilities.

Technologically, the solution is within reach. Multiple promising projects are expected to be and have been investigated and many waste-to-energy plants are already equipped with flue gas condensation, which is a natural first step in the carbon capture process. Waste-to-energy plants in Northern Europe often can utilise the waste heat produced by the carbon capture process, drastically increasing the energy efficiency.

Our world needs solutions for the same challenges which are present in Denmark. This visionary approach to the Danish waste-to-energy sector could advance the carbon capture industry, encouraging more developments and setting an important precedent for future projects.

It is ARC’s plan to build a full-scale plant after the demonstration-scale plant, which will capture up to 95% of the total CO₂ that Amager Bakke emits. This equals at least 500,000 tonnes of CO₂ annually, enabling the city of Copenhagen to become carbon neutral.