CCS + CCGT: a winning combination?28 July 2023
The idea of adding post-combustion carbon capture to combined cycle plants is gaining traction at several locations worldwide, with several projects aiming for “world first” status.
Above: The 700 MWe Cane Run combined cycle plant
Two natural gas fuelled combined cycle plants in the USA, Cane Run (Louisville, Kentucky) and Polk (Tampa, Florida), are currently the subject of post combustion capture FEED studies. These are primarily funded by USDoE, which is providing about $5.6 million to each project.
The Cane Run capture project involves collaboration between PPL Corporation subsidiaries Louisville Gas and Electric Company and Kentucky Utilities Company (LG&E and KU), EPRI, and the University of Kentucky. Bechtel and the University of Michigan are also participating.
LG&E and KU’s 700 MWe Cane Run combined cycle plant, known as CR7, has been in operation since 2015. The Cane Run FEED study aims to evaluate the feasibility and economics of piloting and deploying on CR7 a “low-cost CO2 capture process” developed by the University of Kentucky, employing aqueous amine absorption, with a CO2 capture rate of 95%.
The study will lay the groundwork for a 10-20 MW carbon capture sequestration pilot unit at Cane Run. If the unit is deployed as proposed by the FEED study, it “would be the first of its kind in the world”, say the project participants.
CR7 is representative of natural gas fuelled combined cycle power plants in the US midwest and midsouth and the results of the CR7 project are expected to yield valuable information relevant to retrofitting carbon-capture on other units, they note.
The FEED study will run until mid-2024 and involves pre-FEED research by the University of Kentucky focused on the project scope and design, among other matters. The FEED itself will be conducted by Bechtel, with commercial, environmental and economic assessments performed by EPRI and a life-cycle assessment performed by the University of Michigan.
At the 1190 MWe Polk natural gas fuelled combined cycle power plant, Tampa Electric Company is leading a project team conducting a FEED study on the retrofit of ION Clean Energy Inc’s post-combustion CO2 capture technology.
The Polk site is said to have many features that make it an ideal candidate for applying post- combustion carbon capture, not least favourable geology for on-site large-scale CO2 storage.
The plan is to use ION’s “transformational solvent”, ICE-31, which has been developed by ION and shown to “achieve a minimum of 95% CO2 capture with exceptional long-term stability in NGCC environments.”
In the UK, RWE is looking at the feasibility of retrofitting carbon capture to existing natural gas fuelled combined cycle power plants at Pembroke and Staythorpe, as well as at a new-build 800 MWe combined cycle plant at Stallingborough, close to the Humber Estuary.
As operator of the largest fleet of gas fired power stations in the UK, RWE says it considers CCS to be a viable solution for delivering decarbonised, reliable, and dispatchable power generation, whilst supporting the UK’s target of decarbonising its power system by 2035.
Tom Glover, RWE’s UK country chair, commented: “In order to decarbonise the power sector, support security of supply and enable large scale industrial decarbonisation, it is important that clean gas generation projects are developed. Carbon capture can support the expansion of the other renewable and low carbon technologies...by providing energy security through firm and flexible provision of electricity that is not reliant on weather.”
All three projects are close to proposed CO2 networks or will have access to shipping facilities, which would enable the CO2 to be safely transported and stored by third parties. RWE has developed partnerships with two industrial clusters, South Wales Industrial Cluster (SWIC) and Viking CCS in order to develop these transportation and storage options. Where possible, utilisation options for the captured CO2 will be targeted.
RWE says the projects are now preparing to apply to the UK Department for Energy Security and Net Zero’s “Track 2 Phase 2 cluster sequencing funding application process”, which is focused on supporting carbon capture projects close to carbon capture storage or transport facilities.
As well as in the UK, RWE is also forging ahead with the development of CCS technology in the Netherlands, notably the BECCUS project.
NZT Power delay
Another contender aspiring to be the world’s first gas-fired power plant with CCS is Net Zero Teesside Power (NZT Power) in the UK, which, as reported in last month’s Modern Power Systems (p 30), has been placed on the Track 1 Negotiations Project List by the UK Department for Energy Security and Net Zero (DESNZ) as part of Phase 2 of the Cluster Sequencing process for carbon capture usage and storage. Essentially, this means that the project is in the running for further UK government funding, with a final investment decision expected in 2024.
A Development Consent Order (ie, planning permission) application has been submitted for the NZT Power project, which is an H class combined cycle power plant of up to 860 MWe, with post combustion amine- based capture.
A decision on the NZT Development Consent Order was due to be announced on 10 May but has been delayed to 14 September because some offshore elements of the NZT proposal are in an area earmarked for the proposed Hornsea 4 offshore wind farm.