UKCCSC Theme A – Fossil energy systems, CO₂ capture, transport and utilisation

Page Contents:

• Theme A1 – Fossil Fuel Supply: UK lifecycle costs and emissions with(out) CCS
• Theme A2 – CCS synergies with other low-emission energy sources
• Theme A3 – Fossil fuel and CCS as a bridge to the hydrogen economy
• Theme A4 – Fossil fuel utilisation with CO₂ capture
• Theme A5 – UK Real Time Energy Supply and CCS Plant
• Theme A6 – CO₂ Transport: UK Infrastructure and Regulation
• Theme A7 – Long term utilisation

Theme A1 – Fossil Fuel Supply: UK lifecycle costs and emissions with(out) CCS.

Leader: Timothy Cockerill, University of Reading
 

The fossil fuel supply topic sets out to provide a background for decision making on the role that can be played by CCS in meeting UK energy supply objectives (encompassing economics, climate change and security). The work programme concentrates on lifecycle assessment of the overall costs and CO₂ emissions associated with a variety of non-CCS and CCS fossil fuel supply options, evaluated in the context of possible future energy/supply demand scenarios. Effort will be lead by Reading University (Dr Tim Cockerill), with substantial contributions from Imperial College London and Aberdeen University. Specific objectives include:

Overall assessment of lifecycle costs and emissions of fossil fuel supply options.

Drawing predominantly on the work of others, cost, emission and performance data for supply options available to the UK will be gathered and processed to allow consistent comparisons to be made (Reading University & Imperial College London).

Assessment of the impact of future energy supply/demand scenarios on the overall costs and emissions of non-CCS and CCS fossil generation

Data produced by others on future fossil fuel availability and costs will be summarized, drawing in part on UKERC work on gas supplies (Aberdeen University). The impacts of possible future trends in supply on the lifecycle costs and emissions of non-CCS and CCS fossil generation schemes will be investigated (Universities of Reading &Aberdeen). Analysis will extend to demand reduction strategies, in addition to supply side technologies and biomass combustion, in collaboration with Theme A2. Working with Theme E, the influence of the configuration of a UK CCS system, particularly with regard to the extent to which CCS is employed and the geographical location of plant, will also be investigated (University of Reading). Treatment of CCS schemes will take advantage of an enhanced version of a whole system CCS assessment model.

Summary of published data on fossil fuel utilisation, performance and costs of non-CCS power plant.

A by-product of the work will be the generation of a dataset characterising non-CCS plant under consistent assumptions. The data will be made available to the community, to provide a baseline for the assessment of CCS schemes and in support of other TSEC and UKERC activities (University of Reading).

Theme A2 – CCS synergies with other low-emission energy sources

Leader: Jon Gibbins, Imperial College of Science and Technology, London

Fuels that produce CO₂ when burnt, but are classified as renewable (or CO₂ neutral), such as biomass and certain types of waste, may also be used advantageously to generate power with CO₂ capture. These fuels can be used either alone or co-fired with fossil fuels (e.g. coal). When such renewable fuels are fired alone the power systems are of modest scale, due to fuel availability issues and have relatively low thermal efficiency. However, when low levels (e.g. 5-10%) of such renewable fuels are co-fired with fossil fuels, potentially high efficiency systems are possible which would be more suited to CO₂ capture; indeed co-firing allows for the level of CO₂ capture to exceed 100% of that derived from the fossil fuel alone. Some gasification systems developed for fossil fuel firing also have the capability to be fired with renewable fuels. The fuel gases from such systems can be used to fire gas turbines, to produce chemical feedstocks or to produce hydrogen.

A further issue arises from the interaction between fossil fuel (and biomass) fired power systems with CO₂ capture and other intermittent or less flexible low emission power systems (e.g. wind, nuclear and heat constrained Combined Heat and Power (CHP)). Activities in this theme will investigate the impact of using renewable energy fuels in combination with a range of CO₂ capture technologies in existing and future power systems, including:

• Realistic carbon capture scenarios; including interaction of potential fuel supplies/costs, CO₂ capture technologies, power system demands (e.g. cyclic operation) and regulation effects.
• Evaluation of alternative carbon capture technologies in terms of their suitability for use on these particular types of power systems.
• Candidate renewable fuels: availability, supply and potential interactions with capture technologies.
• Quantification of the benefits of using co-firing of renewable fuels.
• Modelling the linkage of using intermittent / inflexible wind / nuclear / heat constrained CHP power, in combination with fossil fuel / co-fired power systems, in terms of the overall CO₂ reduction that could be achieved in different energy demand scenarios.

Theme A3 – Fossil fuel and CCS as a bridge to the hydrogen economy

Leader: John Oakey, Cranfield Unversity

Fossil fuel gasification with CCS is generally recognised as the cheapest short to medium term solution for hydrogen production with limited CO₂ emissions. Further, steam reforming of methane is the established route for hydrogen production at oil refineries and, like coal gasification, this can readily be adapted for CO₂ capture. In terms of the future balance between natural gas and coal gasification, the key issue facing the UK is the long–term security of supply and price for imported natural gas. Globally coal will clearly remain important (e.g. continued dominance in USA, expansion of electricity supply in China) and, if natural gas prices do increase in relation to coal, then there will be a likely need for coal gasification with CCS to provide hydrogen for both generation and transport beyond 2020.

The results from current techno-economic assessments will be evaluated to characterise the technical options and costs for hydrogen production from fossil fuels, including combined electricity and hydrogen production from new gasifier systems currently being developed in the UK. To assess the scope for hydrogen production from fossil fuels, combined with CCS to help start a hydrogen economy, the likely uptake of gasification technology, both for coal and natural gas and the balance between these, will be assessed, in addition to the uptake of integrated gasification combined cycle gasification (IGCC) of coal for power generation. The catalytic cracking of methane at relatively low temperatures (ca. 650^oC) will be investigated to develop alternative technology options for hydrogen production where a valuable form of carbon (nanofibres), as opposed to CO₂, is produced as the by-product. This opens up the possibility for kick-starting local hydrogen production from sources such as coal-bed methane.

Theme A4 – Fossil fuel utilisation with CO₂ capture

Leader: John Oakey, Cranfield University

Fossil fuel power systems using coal, oil and natural gas are established technologies that have proven highly reliable and flexible in meeting the power requirements of many developed and developing countries over many tens of decades. In recent years in the UK, they have evolved to combine high efficiency (and hence low emissions) with the operational flexibility to meet the demands of a deregulated electricity market with pressure on operating costs. To provide sustainable electricity supplies to UK customers, the future mix of electricity supply technologies must retain this high degree of flexibility. The current UK supply market comprises a viable balance of fossil, nuclear and renewable systems but this is planned to change with a decrease in the extent of highly inflexible nuclear generation being replaced by similarly inflexible renewable technologies, primarily wind and wave driven. Thus, the continuation of flexible fossil (and biomass) derived electricity is a key element of the required future mix if we are to maintain security of supplies to domestic and industrial customers without incurring additional costs of reversing the deregulation trend.

This theme addresses the key issue of maintaining plant flexibility while introducing existing and advanced CO₂capture technologies in order to meet the UK’s environmental targets. To achieve this, a number of tasks are planned:

• A review of the performance standards required to retrofit CO₂ capture systems on existing and new fossil plants in order to complement increasing levels of intermittent renewable power systems. This will involve liaison with power utilities and the current suppliers of CO₂ capture equipment, in order to determine the impact of combining these technologies. For example, it may not be possible for some capture technologies to follow the load cycle demands of current and future power plants. It may therefore prove necessary to be able to switch the capture plant in and out of circuit, in order for the plant to continue to produce power at all load factors, which would have a corresponding impact on operating costs. Above all, reducing the operability of fossil plants to that of nuclear plant must be avoided if the planned growth in renewables is to be realised.
• Evaluation of new alternative CO₂ capture technologies (for gasification and combustion power plants) that offer increased efficiency, flexibility and/or tolerance to fossil fuel derived contaminants.
• Studies of future CO₂ capture systems will identify those with the most potential for integration with likely developments of fossil power technologies, e.g. ultra-supercritical pulverised coal, coal gasification and gas turbines fired on fuel gases of reduced quality, such as imported natural gas, coal/biomass/waste gasification gas, and synthetic natural gas, including the introduction of hydrogen. In addition, the cost of achieving high levels of CO₂ capture will be studied, to identify the optimum capture performance in the context of a flexible power plant producing low cost electricity. This task will have to consider the traditional, conservative, risk-averse nature of the power generation industry, which will be reluctant to add CO₂ capture systems that too closely resemble chemical plants onto traditional combustion based power systems. However, a different attitude may be acceptable if the step towards gasification based power systems is made.
• A number of realistic CO₂ capture scenarios will be defined and investigated for UK based power plants, including quantitatively assessing the benefits / penalties that carrying out CO₂ capture will cause in terms of: power generation economics; plant RAMO (reliability, availability, maintainability and operability); flexibility of plant operation (e.g. times to achieve transitions between start-up / shut-down / idling); potential actual plant efficiencies when used for short or long periods; alternative uses for the CO₂ and their impact on power plant operation and economics; energy penalty of using CO₂ capture systems (due to reduced plant output, etc).

Theme A5 – UK Real Time Energy Supply and CCS Plant

Leader: Goran Strbac, University of Manchester; Jon Gibbins, Imperial College of Science and Technology

Details to be posted here.

Theme A6 – CO₂ Transport: UK Infrastructure and Regulation

Leaders: Martin Downie, University of Newcastle

The individual components of carbon capture and storage offshore have all been shown to be potentially viable, and have been demonstrated at (relatively) small scale. The application of the process on a nationwide scale leaves a number of areas to be more fully investigated. To do so involves a number of activities including:

1. Identifying, locating and classifying the sources in a comprehensive manner,
2. Identifying and locating suitable offshore sites for EOR and/or storage, and
3. Developing/ designing/ modelling transport systems to bridge the two.

The associated issues include technical and economic viability, safety and monitoring, environmental impact, societal acceptance, policy and regulation. This topic is primarily concerned with these issues in relation to the third activity but involves interaction with the other two, which will also have strong synergies with the ‘Carbon Storage’ activities of the UKERC. The objectives are:

• To assess technical requirements and likely costs for onshore and offshore CO₂ transport systems in the UK;
• To devise possible CO₂ transport systems for the UK, including rational development and closure strategies;
• To examine the viability of existing infrastructure for CO₂ transport; To report what additional regulations may be needed for CO₂ transport and how might they affect system design and equipment choice;
• To assess likely specifications and costs for offshore and onshore CO₂ injection and, for EOR, reprocessing equipment.

In order to achieve the objectives, it will be necessary for the investigators to interact with those contributing to themes A1: Fossil fuel supply; B2 Hydrocarbon fields and added value from CO₂; C, CCS and the environment, and E1 GIS. The technical assessment and analysis of the multi-source/multi-storage transport systems will be carried out principally by University of Newcastle with input from the BGS with respect to GIS, University of Reading on the techno-economic modelling and University of Nottingham on terrestrial environmental impact. The interaction will be two way, with data and results generated in B2 feeding back into the contributing topic areas. The technical input relating both to on- and offshore transport, existing infrastructure, and technology gaps, will be informed by the University of Newcastle’s strong relationship with the pipeline engineering and the oil and gas industries.

Theme A7: Long term utilisation

Leader: Mike George, University of Nottingham.