Can BECCS make an impact?
Chair: Mohamed Pourkashanian, University of Sheffield
Hannah Evans, ETI
Bioenergy with CCS (BECCS) is a credible, scalable and efficient technology, and is critical to deploy in order for the UK to meet its 2050 GHG emission reduction targets cost effectively.
Evidence from ESME, the ETI’s peer-reviewed energy system modelling environment, suggests that by the 2050s, BECCS could deliver c.-55 million tonnes of net negative emissions per annum (approximately half our emissions target in 2050), whilst meeting c.10% of the UK’s future energy demand. Achieving this would reduce the cost of meeting the UK’s 2050 GHG emissions target by up to 1% of GDP.
The UK is well-placed to exploit the benefits of BECCS, given the vast storage opportunities offshore around the UK; our experience in bioenergy deployments; and our academic and industrial research and development strength across bioenergy and CCS. The ETI’s recent insights paper, The Evidence for Deploying BECCS in the UK, argues that major advances in the fundamental science and technology development have been made over the last ten years, significantly de-risking this value chain such that, with the right support, BECCS could be deployed by 2030.
Patricia Thornley, University of Manchester
This presentation will evaluate the environmental impact of BECCS systems, including assessment of the greenhouse gas balance and critique of key parameters critical to delivering negative emissions. Consideration will be given to the availability of biomass resources commensurate with BECCS ambitions and the wider sustainability issues that need to be managed to ensure sustainable development of BECCS. While the main focus of the presentation will be on carbon balances, the importance of other environmental impacts as well as social and economic trade-offs will be emphasized. The need for an appropriate framework to maximize benefits and avoid damaging impacts will be emphasized and the challenge of developing appropriate policy incentives.
Understanding micro to macro scale processes
Chair: Stuart Haszeldine, SCCS/University of Edinburgh
Stuart Gilfillan, University of Edinburgh
Residual CO2 trapping is a key mechanism of secure CO2 storage, and is hence an essential component of the Carbon Capture and Storage technology. Estimating the amount of CO2 that will be residually trapped in a saline aquifer formation remains a significant challenge. Here we present oxygen isotope ratio (δ18O) measurements from a single-well experiment, the CO2CRC Otway 2B Extension, and use them to estimate levels of residual trapping of CO2. Following the initiation of the drive to residual saturation in the reservoir, reservoir water δ18O decreased near the well, compared to baseline conditions, over a time span of only a few days. This can be explained by
isotope equilibrium exchange between residually trapped CO2 and water. This indicates that enough oxygen sourced from CO2 was available in the reservoir to change the oxygen isotope signature of the reservoir water after only a few hours. This provides a residual saturation estimate of 14 ± 9%. For the region further away from the well, the observed isotopic shift in the reservoir water can also be explained by isotopic exchange with mobile CO2 from ahead of the region driven to residual, or continuous isotopic exchange between water and residual CO2 during its back-production. The uncertainty surrounding the contribution of each process to alteration of δ18O in the reservoir waters complicates the interpretation of the change in terms of residual saturation in the later stages of the experiment.
Sam Krevor, Imperial College London
The characteristic flow properties – capillary pressure, absolute and relative permeability, and residual trapping – were measured in samples obtained from the Captain sandstone, the Ormskirk sandstone, and the Bunter sandstone, all important target reservoirs for CO2 storage in the UK. In all cases, relative permeability and trapping behaviour were characteristic of water wet rock systems. In particular, residual trapping will be a significant contributor to CO2 immobilisation in the reservoir and this dataset should provide amongst the first data from UK reservoir systems. Rock heterogeneities had significant impacts on both fluid flow and trapping. This was particularly the case when flow properties were measured in the capillary limit representative of far field fluid flow. Relative permeabilities at low capillary numbers were typically an order of magnitude lower or higher (depending on the orientation of layers) than relative permeability measured in the viscous limit characteristic of the near wellbore system. Capillary trapping was not systematically affected by flow regime, but large deviances of trapping data from the initial-residual curve were the result of the impact of heterogeneity. In most cases heterogeneities lead to increases in trapping.
Haroun Mahgerefteh, UCL
Highly-depleted gas fields represent prime potential targets for large-scale storage of captured CO2 emitted from industrial sources and fossil-fuel power plants. The most effective way of transporting the captured CO2 for subsequent sequestration using high-pressure pipelines is in dense phase. The CO2 arriving at the injection well will typically be at pressure greater than 70 bar and at temperatures between 4 and 8 ºC. Given the substantially lower pressure at the wellhead, the injection of CO2 will result in its rapid, quasi-adiabatic Joule-Thomson expansion leading to significant temperature drops. This could pose several risks, including hydrate and ice formation around the wellbore and thermal shocking of the wellbore casing steel, leading to its fracture and ultimately escape of CO2. The development and testing of a model for the simulation of the highly-transient multi-phase flow phenomena taking place in wellbores during the start-up injection of CO2 mixtures into depleted gas fields is presented. The model provides a basis for the development of optimal injection strategies and best-practice guidelines for the minimisation of the risks associated with the start-up injection of CO2 into highly-depleted gas fields.
Hayley Vosper, BGS
This presentation is based on the results of the Call 2 project ‘MSc-UK: Multiscale Characterisation of CO2 Storage in the United Kingdom’, and focuses on using reservoir simulation to estimate the effects of new relative permeability data and hysteresis on capacity estimation. Firstly, we look at the effects of hysteresis on the CO2 plume itself. This is done using a model of one of the structural closures in the Bunter Sandstone (Southern North Sea) and a range of relative permeability data generated in an earlier part of the project. Secondly, dynamic capacity estimates of a regional model of the Bunter Sandstone are presented, based on realistic well configurations, pressure limitations, new relative permeability data and incorporating a seabed outcrop. Finally, we consider the South Morecambe field. This is a large, currently producing gas field in the East Irish Sea, requiring compositional simulations to account for the distinct properties of methane and CO2. A purpose-built model of the field is used to provide dynamic and volumetric capacity estimations.
CCR and Commercialising CCS
Chair: David Reiner, University of Cambridge
Jia Li, GDCCUSC
Capture Ready for Chinese Power plant: Designing 1GW capture ready power plant in China; Experience learned from a Chinese natural gas capture ready plant; New policy suggestions to make Chinese power plant capture ready.
Phil Macdonald, Sandbag
What will it take to secure civil society and public support for CCS? CCS is essential to tackle climate change. The bible of the environmental movement, the IPCC’s AR5, is explicit in its climate model’s reliance on CCS to stay below 2 degrees. And yet, CCS is not widely supported by green groups, and is publicly invisible. A concept used for decades as a fig-leaf for continued unabated fossil fuel burn, CCS has been renewables’ poor and ugly cousin, hiding in the shadows whilst wind and solar became the darling of the decarbonisers. Is there any hope that CCS be rehabilitated? Here we discuss how with a new focus on industrial CCS, jobs in the North Sea, and the eventual necessity of BECCS to avoid two degrees of warming, Carbon Capture can become a technology and industry with wide public support. Can CCS grow incrementally rather than through major projects? Will shipped storage and linking with hydrogen generation help CCS gain a foothold in the UK decarbonisation mix?
Ian Temperton, Ian Temperton Consulting
Ian will draw largely on the work of the Parliamentary Advisory Group on CCS to discuss commercial and financing models which will work for the development of CCS.
Jim Skea, Committee on Climate Change
The ambition of the 2015 Paris climate agreement has underlined the need to develop, demonstrate and commercialise technologies and practices that result in the removal of carbon dioxide from the atmosphere. Yet, as UNEP has shown in its gap report, the distance between countries’ aspirations and their pledges, never mind their actions on the ground, is considerable. At the same time, there has been a push-back against the possible sustainability impacts of deployment, at scale, of carbon dioxide removal technologies such as BECCs. For the first time, IPCC will need to consider not only the impacts of climate change but also the impacts of the deployment of mitigation technologies. This presentation will set out the nature and scale of the current challenges, indicate how IPCC might address these issues during its sixth assessment cycle and identify some challenges for the CCS community.