PilotSTRATEGY has made one of its biggest decisions to date – whether to proceed with research into pilot storage sites offshore or onshore in Portugal and Spain. In the end, the two teams took different routes: Portugal decided to pursue offshore storage while Spain opted for onshore.
In Portugal, the team opted to continue research for a pilot storage site offshore in reservoirs in the Cabo Mondego & São Pedro de Muel Lusitanian 3D seismic block. The study area extends 20km north from the coastal city of Figueira da Foz down to the southern limit of the block, offshore from the traditional fishing and surf town of Nazaré.
“The quality of the existing geological and geophysical information was the key argument favouring offshore,” said Prof Júlio Carneiro of the University of Évora. “With the available data, we know the offshore has the best technical conditions for the pilot.”
The team ended up examining three sites – two onshore and one offshore – after the original onshore option, in the Alcobaça area did not meet the technical criteria for the pilot. It examined a second onshore site in the Monte Real area but there was insufficient existing geological and geophysical data to move forward with it within PilotSTRATEGY timelines. However, the Évora team considers it sufficiently promising to continue to study it outwith the project.
Looking ahead, Prof Carneiro says that selecting the offshore site brings two further challenges: regulation and cost.
“Regulatory issues for the offshore are less clear than for the onshore. CCS activities will follow the procedures of the CCS licensing authority in the country (DGEG), which are clear and based on the transposition of the CCS Directive to the national law” he says. “However, offshore activities must also be granted a permit of private use of the maritime space. Currently CCS is not included in the list of uses eligible for such a permit, so further work on clarifying those regulations will be necessary.
“Costs for the pilot will be certainly higher than for the offshore, so the pilot needs to be planned in a broader context of upscaling it to commercial storage site once the pilot successfully demonstrate the adequacy of the site,” he says.
“My personal opinion is that these will be two important contributions of PilotSTRATEGY for CCS deployment in Portugal. We would need to clarify the offshore regulation issues in any case, since onshore storage capacity is limited. Also, since the long-term solution for CO2 storage in Portugal will have to rely on the offshore, it may make more sense, even economically, to invest right now in the offshore instead of building CCS infrastructure onshore and then having to do it again in the offshore when the capacity onshore is exhausted.”
In Spain, the team has opted to continue working onshore in Lopín site, close to Zaragoza, in the so-called “Campo de Belchite”.
“It was a very difficult decision. From the information available, both sites were equally valid from a technical point of view and no relevant risks were identified for either of them,” says Dr Paula Fernández-Canteli of the Instituto Geológico y Minero de España (IGME), the Geological Survey of Spain. “Also, the proposed sites are very different not only in location but in geology, studies available, or volume and quantity of data. As a result, the decision was only possible using a multicriteria approach, reviewing all different criteria - technical, environmental, social, economic, legal, fit for project objective.
Despite the difficulty, it was a unanimous decision “which gives us confidence in the process and in our choice” she says.
With both sites considered technically possible, two criteria moved the balance in favour of the onshore site – social acceptance and being fit for the project’s objectives.
“There was slightly better social interest in the onshore site and also it presents less difficulty from the legal, administrative and economic points of view,” she says.
“Another favourable point of the onshore site is its potential for replicability, since many Spanish industries are currently studying possibilities for CO2 storage based on the existing Spanish onshore CO2 storage sites atlas.”
The team is now focusing on finalising the geological model and organising the first regional stakeholder committee.
“All of this will allow us to design the technical, societal, economic and legal framework for the development concept of the pilot,” she says.
Dr Fernanda M L Veloso of BRGM, the French Geological Survey, and PilotSTRATEGY’s project coordinator, said: “My thanks go to all the colleagues involved in these important decisions, made on social as well as technical grounds. We are delighted to be working in two such promising areas and addressing the shortage of CO2 storage sites in southern Europe.”