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CO2 scrubbing costs less on the continental shelf

Measures such as those already implemented on the Sleipner offshore gas-field in Norway are the most reasonably priced that the Nordic countries can go for in the CCS field. Here, CO 2 from the natural gas reservoir is brought back to the continental shelf. Illustration: Statoil
Of all the CO2 that is produced in the Nordic countries, the cheapest to deal with is what is produced together with natural gas from offshore gas-fields.

Just a short time after Norway’s “red-green” coalition government shelved full-scale CO2 capture and storage at Mongstad near Bergen in Western Norway, Scandinavian scientists have classified potential Nordic CCS projects in order of cost. 

It turns out that the most reasonably priced measures are similar to those that Statoil has already implemented on the Sleipner and Snøhvit offshore fields; i.e. capturing and storing CO2 that has been trapped in natural gas reservoirs and is inevitably brought to the surface together with the gas in the course of production.


Hoping for a kick-start

Nils A. Røkke, climate technology director at SINTEF, which is one of the research institutes involved in the joint Nordic study, regards CCS projects linked to future gas-fields as potential door-openers for CCS in the Nordic countries.

With the possible exception of scrubbing natural gas, all CCS projects in the Nordic countries today must include a revenue element in order to be profitable, say SINTEF’s Mazzetti and Røkke. Using CO2 to increase oil recovery rates is the most realistic way of doing this, they claim. Photo: SINTEF

“Natural gas scrubbing is the lowest-hanging fruit in this regard. If we can install CCS plants on gas fields and use the CO2 for enhanced oil recovery, projects of this sort could kick-start a market in which onshore industry could also be paid to supply CO2 to the petroleum sector,” says Røkke.


€50 a tonne

The cost of processing CO2 from gas fields is estimated by the Nordic report to be around €50 a tonne. According to Røkke, CCS projects of this type also incorporate a revenue side.

“When CO2 is scrubbed and separated out of the product from a gas-field, the seller will be able to carry more gas in the pipeline. This means extra income, which can make a worthwhile contribution to paying for CCS,” says Røkke.


Not liable to quotas – yet

The CO2 in gas reservoirs was formed through the transformation of plant and animal remains, just like the natural gas itself. The concentration of CO2 differs from one field to another. In the gas Norway supplies to Europe, the concentration must not exceed 2.5 per cent. At the export terminals, gas from different fields is mixed into a “cocktail” that satisfies this requirement.

The CO2 that remains in the export pipelines ends up as emissions in other countries. At present, therefore, it is not subject to Norway’s CO2 quota. However, according to Røkke, this could change.


Cement and refineries

The report ends up with a Nordic route-map for CCS that shows that the second-cheapest group of CCS projects includes Portland Ålborg's cement factory in Denmark as well as Norcem Cement in Breivik, Norway, the Preem Refinery in Sweden and Rautarukki Steel Mill in Faludden, Finland, and a Norwegian gas-fired power plant that could supply electric power to offshore platforms. In this group, the processing costs lie at around €60 per tonne of CO2.

SINTEF scientist Marit Mazzetti has played a central role in drawing up the Nordic report. She says that the first plant to be built will cost more than the report estimated. Mazzetti adds that the cost estimates are based on a mature technology, and that further developments in the technology involved will reduce costs.


Enhanced oil recovery

With the possible exception of scrubbing natural gas, all CCS projects in the Nordic countries today must include a revenue element in order to be profitable, say Mazzetti and Røkke.

“Using CO2 to produce more oil from reservoirs is the most realistic means of achieving this,” says Mazzetti, as she mentions that the USA has been creating profitable CCS projects in this way for 30 years.

“When Canada becomes the first country in the world to generate electricity from coal-fired power stations with CCS next year, it is just the use of CO2 to increase oil recovery rates that will enable the project to be realised,” she points out.

by Svein Tønseth 

Nordic CCS roadmap 

  • Scientists have circled in the cheapest CCS measures in the Nordic region, as part of efforts to produce a Nordic CCS route-map. 
  • The main message of the route-map is that cooperation will give the Nordic countries new ways to shrink the high level of costs that are currently holding back the implementation of carbon capture and storage. 
  • By working in concert, the Nordic countries will greatly expand their potential to achieve large-scale savings over what they would have managed by operating alone. The synergy effects are based on the situation that Finland and Sweden produce large, highly localised emissions of CO2 from power stations and industrial plants, while Norway and Denmark have huge offshore capacity for CO2 storage. 
  • Sweden and Finland use a great deal of bioenergy in their industrial and electricity-generating sectors, and bioenergy is regarded as climate-neutral (i.e. its CO2 emissions have no net greenhouse effect). Using CCS to deal with such emissions actually removes CO2 from the natural cycle. Measures of this sort are important weapons in the struggle to save our climate. 
  • The route-map is drawn up by NORDICCS Competence Centre, a virtual carbon capture and storage (CCS) networking platform aiming for increased CCS deployment in the five Nordic countries. 
  • The centre comprises Nordic 11 research institutes and universities, in addition to a number of industrial partners. The Centre is financed by the Nordic Top-Level Research Initiative (TRI).