Common misunderstandings about CCS

All new and large-scale technologies are often met with scepticism since they seem scary, and CCS - Carbon Capture and Storage - is no exception.

The public debate regarding CCS has grown in recent years, which is good, but misunderstandings and misinterpretations are common in the dialogue.

In this article from the CCS newsletter - Bridging to the Future - Vattenfall wants to straighten out some important areas of confusion and also clarify its position on ten subjects.

1. Is there global consensus on combating climate change?

Most of the world’s leaders recognize the climate change issue and are well aware of the necessity of taking action.

However, there are many countries that have other more prioritized issues on their agendas. For them, the utilization of domestic fossil resources is a means of reaching other objectives with a higher priority. CCS gives hope since it has potential to be affordable also to economies in transition.

2. Could the world be made independent of fossil fuels within a couple of decades?

Fossil fuels have their role and will continue to play a role in global energy supply for a long time to come. There is no way that the world could make itself independent of fossil fuels within the next two decades. Fossil fuels are a far to powerful tool for reaching other important goals.

A functioning energy supply system is a cornerstone of the infrastructure and society at large - it provides added value to people. In western society we have had this for so long that we now take it for granted. In developing countries and economies in transition, improved energy supply is a tool for reaching other goals such as economic growth and improved living conditions for the population.

Today, 65 per cent of the world's electricity generation is based on fossil fuels. Fossil fuels now account of 80 per cent of the total energy supply. Fossil fuels are competitive, are found everywhere, are easy to use and can easily be transported.

3. Does CCS waste energy?

CCS plants use more energy for their own processes than traditional power plants with combustion. However, using energy to prevent CO₂ emissions to the atmosphere is not a waste of energy - it is a good use of energy. Future commercial power plants with CCS will probably be more energy efficient than the global average of existing power plants today.

Energy is needed to capture CO₂. The oxygen generation (air
separation) required for both the Oxyfuel and the Precombustion capture processes uses energy. Both Postcombustion and Precombustion processes need energy to re-release CO₂ after amines or other absorbents have absorbed it. Once the CO₂ has been captured it needs to be compressed before cost-efficient transportation. This process also uses energy.

These processes use energy that otherwise could have been used to generate additional electricity. However, some of the losses in electricity generation could be used for heat production. Therefore, Vattenfall strongly believes that commercial CCS plants would achieve improved competitiveness as CHP (Combined Heat and Power) plats.

It is believed that the learning curve for CCS will be quite fast.
The technology is still young and there is great development potential. For example, Vattenfall believes that it would be possible to build Oxyfuel plants by 2030 with higher electricity efficiency than could be built today using the best commercially-available technology.

4. Can CCS deliver in time?

There are strong reasons to believe that CCS could deliver in time to become a powerful tool in the struggle to significantly reduce global CO₂ emissions and thereby combat global climate change. No other single measure has the same potential.

Vattenfall strongly believes that CCS could become commercial under the emission-trading scheme in Europe by 2020. Thereby, it has commercial potential to become a powerful tool to reduce CO₂ emissions. Other measures, such as increased energy efficiency and renewables like wind power could deliver faster, but on a smaller scale. It is, however, important to remember that all measures are needed to handle the climate change issue.

It is also important to recognise the world's dependence on fossil fuels and that the vast majority of newly constructed power plants, both in Europe and in developing countries, are fired with fossil fuels, usually coal.

The best Vattenfall and Europe can do is to show the rest of the world that CCS is possible and that the cost for it is affordable. If we can do this, the rest of the world will follow and a significant global reduction of CO₂ emissions could be achieved.

5. Does CCS reduce efforts to develop renewable and sustainable technologies?

Efforts to develop CCS do not reduce efforts to develop renewable and sustainable technologies. CCS is a powerful complement.

CCS is no silver bullet; it is an intermediate solution along the road to a global low-carbon of CO₂-neutral society. But, CCS does not have the potential to reduce all CO₂ emissions. It could be applied to large point sources but would be too costly for small, outspread sources. CCS is not seen as an option for the transport sector.

Therefore, all the players in the energy sector are given high priority to the continued development of renewable and sustainable solutions. Based on the information available today there is no hope that these technologies could become mature enough to replace the fossil fuels within a reasonable time.

6. Is CO2 dangerous?

CO₂ is in itself a harmless, non-toxic and non-flammable gas.

CO₂ occurs naturally and is a prerequisite for life on earth. Large volumes of concentrated CO₂ need to be handled with caution since it is a heavy gas and could in theory gather in pits by pushing away the oxygen-containing air that we need in order to breathe. Technologies for and knowledge about handling large volumes of gases, even dangerous ones like methane (natural gas), exist and are well proven. The large-scale handling of CO₂ is well-known, safe and secure.

The combustion of fossil fuels adds CO₂ to the atmosphere where its increasing concentration causes changes in the climate. CCS is a means of drastically reducing CO₂ emissions from fossil fuel-fired power plants and other point sources.

7. Is it risky to store CO2 underground?

The risks associated with CCS are well known and we have both the skills and the technology to handle them. These risks are, however, small in comparison to the risks we face without CCS: either to ignore the climate change issue or to try other paths to reduce the global CO₂ emissions within a reasonable time.

We know that the three parts of the CCS chain, capture, transport and storage, work and that they can be performed safely – at the power plant, along transport routes, during injection and after sealing the storage facility. Smaller pipeline leakage can be easily detected due to sharp temperature falls near the fault. Larger ruptures can be quickly terminated by automatic shut-offs and safety devices. CO₂ that is expelled under strong cloud and dry ice formation will mix with the turbulent surrounding air and not gather invisibly on the ground.

Storage will take place in the same kinds of formation in which oil and natural gas are found. CO₂ accumulation occurs in nature all around the world. Since these formations can hold natural gas and naturally occurring CO₂, they can also safely store injected CO₂.

8. Could it be faster and cheaper to reduce CO2 emissions through energy saving and installing more renewable energy sources?

We have to use all the available options to reduce global emissions of CO₂ to limit the consequences of the ongoing climate change. The increased use of existing low-carbon energy sources and the development of new energy sources are most important in combination with energy savings.

However, this is not enough. We cannot replace the fossil fuels that represent 80% of the total energy supply within a reasonable time. CCS is needed as a bridging technology.

There are two remaining big challenges regarding fossil fuels that we have to handle; a) the CO₂ emissions and b) the fact that fossil fuels are a limited resource that sooner or later have to be replaced. The more we increase our use, the faster we need to find replacements.

CCS offers an opportunity for relatively rapid, significant and affordable reductions of CO₂ emissions. Commercially introduced, it will give us some breathing space. In parallel, tomorrow’s truly sustainable solutions regarding our energy supply are being further developed to become mature enough to replace fossil fuels on a large scale. This is why Vattenfall calls CCS a bridging technology.

9. Is CCS expensive?

It costs more to build and run a power plant with CCS than a power plant without CCS. However, no measures other than CCS have the potential to become powerful tools both in terms of rapid CO₂ reduction potential and affordability.

At present, several pilot and demonstration plants have been announced – plants that would cost much more than traditional, commercial plants. However, these plants are prototypes and prototypes are always costly. The costs of demonstration plants should not be mistaken for the costs of the fully-developed commercial CCS plants.

To develop CCS concepts causes additional costs per tonne captured, transported and stored CO₂. However, CCS would become commercial as soon as the cost imposed by the EU Emission Trading Scheme is met. 

10. Would CCS applied to biomass create CO2 sinks?

The technology for capturing CO₂ would work on concentrated point sources from all fuels, including biomass. However, CCS would always be most beneficial, both in financial and CO₂-reduction terms, when applied to large, base load, coal-fired power plants.

Applying CCS to biomass would create CO₂ sinks – CO₂ would be taken up from the atmosphere by the biomass during the time it is growing, be removed from the flue gases after combustion and finally be stored deep underground.

As long as the world is dependent on fossil fuels for its energy supply, it would be most beneficial, both in financial and CO₂-reduction terms, to apply CCS technology to coal-fired power plants, but also to other base load point sources such as metallurgic plants and cement factories with a high concentration of CO₂ in their flue gases.

Biomass combustion also creates flue gases with high CO₂ concentrations. Therefore CCS applied on biomass could be a more cost-efficient way to reduce CO₂ emissions than if applied on, for instance, smaller gas-fired plants. CCS on biomass could also be used as sinks in larger complex systems where it would compensate for many small diffuse CO₂ emission sources such as fleets of fossil-driven vehicles.