Dr. James Glynn:

To stop rising temperatures, we need to stop emitting CO2. That is as clear as we can put it. Sequestration of CO2 through afforestation, CCS, direct air capture and enhanced weathering is critical. We definitely need afforestation as well as any other way to prevent the emission of CO2. The IPCC is highlighting direct air capture, enhanced weathering and CCS in its analysis. Bioenergy carbon capture and storage is the big question. What is the global resource? It is about 50 EJ now. In some scenarios, there is talk of trebling that or even an increase of up to 15 times that amount. That is the big question on CCS.

In the plants we visited in the United States, the most mature plants are capturing about 1 million tonnes to 1.5 million tonnes of CO2 per year. Those plants are in place because of tax regimes in Texas and Canada, where carbon taxes are about $50 per tonne. Some are in the form of rebates and some are investment charges on the cost of electricity. In the scenarios coming from the IPCC, in all of the integrated assessment models produced, bioenergy CCS, or CCS in general, is not for power generation. It produces small amounts of electricity to stabilise the grid but it is mainly to produce liquid and gaseous zero emission fuels for transport and industry. Those are sectors where it is otherwise really difficult to bring CO2 emissions to zero. In the long-term then, CCS will be concerned with zero emissions and liquid and gaseous fuels. Developing the technology is the main aspect of CCS in the short term but whether that technology is then used for fossil fuel or bioenergy in the long term is up for debate.