Vurdering av potensial, muligheter og barrierer for CCS fra biogassproduksjon i Norge

Background and project purpose?
Crude biogas from anaerobic digestion contains approx. 36% CO₂ that will normally find its way back to the atmosphere. When upgrading biogas to biomethane, the CO₂ part is vented at a high concentration. An alternative is to capture the emissions and store them permanently in geological formations (CCS).

Storage of such biogenic CO₂ can be considered as negative emissions and the additional costs of capture and storage can be relatively low, depending on volumes and location. The infrastructure can be retrofitted to existing facilities and integrated into future facilities. In this way, CCS may represent an additional climate upside in biogas production.

What was the project objective?
This study examines the costs of implementing CCS at biogas plants in Norway and the potential up to 2030. Relevant incentives are also examined.

What has the project done in terms of activities?
The project has investigated the potential for biogas with CCS, carried out a cost analysis and analyzed incentives that may be relevant.

What has the project achieved? Did the project achieve its objectives?
Yes, the goals were achieved. The study shows that the additional cost of handling CO₂ from the upgrade process is approx. NOK 1070 per ton, including storage. This presupposes that several facilities can share the costs of establishing and operating transport infrastructure.
Northern Lights may be one of several players that offer coastal transport and permanent storage of CO₂ in Norway in 10 years, but so far they are the only player that has started with the construction of facilities and tankers. The Northern Lights service has therefore been used as a basis for transporting CO₂ from Norwegian ports in this study and this tariff is included in NOK 1,070 per ton.

The results from the study are based on a description of a reference plant for biogas production that is assumed to be of realistic size and distribution in Norway in 2030. The description is derived from a previous study; The resource basis for biogas production in Norway in 2030 (Carbon Limits, 2019).

A case study for the Bekkelaget sewage treatment plant in Oslo shows that despite the short distance to the port, the additional cost increases to approx. NOK 1,200 per ton due to the smaller size of the plant.

It is assumed that the CO₂ gas has been liquefied at all biogas plants prior to transport to port. This is done to increase the density during transport and meet purity requirements for Northern Lights. Water, oxygen, methane and other unwanted components can be removed most efficiently during the liquefaction process which produces CO₂ in the liquid phase at approx. 17 bar and -25 degrees C. These are standard transport conditions for CO₂ today.

The conclusion from this study is that biogas production in combination with CCS can be an attractive climate measure to generate negative emissions. A combination of highly concentrated CO₂ sources and available storage services in Norway (Northern Lights) contributes to lower costs, while relatively small and scattered biogas plants contribute to increased costs.

Future plans?
In the next few years it seems that voluntary schemes hold the greatest potential for financing biogas with CCS in Norway, but it is conceivable that relevant instruments will be introduced at EU level by 2030. These may stimulate commercial actors to create the value chain described here.