Value chain · CLM-1427
In plain terms
The UK government says its 2020 figures for the wider grid cost of each type of power station show how one small extra plant would change costs, compared with a nuclear plant. They are not the total cost of running a whole power system, and they change with the rest of the system.
The claim as recorded
BEIS states that its enhanced levelised costs do not show the full system cost of different pathways but indicate the relative marginal impact of a hypothetical small increment of each technology in each scenario. Its wider system impacts count a technology's discounted impact on the wholesale market, the capacity market, balancing and ancillary services and transmission networks to 2050, divided by its discounted generation; they exclude distribution networks, are presented relative to a nuclear plant, and BEIS calls them entirely system dependent.
Evidence behind this: T3: a UK government department's cost report with a published method (Section 7 and its 2017 framework).
Scope and limits
UK, the 2020 report, for plants commissioning in 2025, 2030 and 2035. A statement of what those figures measure, not a cost figure. It does not say system costs of wind and solar are small or large; only that these marginal, nuclear-relative estimates cannot be read as a whole-system cost. Not additive with, and not on the same basis as, any other claim in the QST-021 GB cost set.
What it assumes
No assumptions are recorded against this claim.
Where it comes from
p.42 (PDF p.44): "Importantly, enhanced levelised costs do not show the full system cost of different pathways but provide an indication of the relative marginal impacts of different technologies to the system in different scenarios." Wider system impacts represent a technology's "discounted impact on the wholesale market, capacity market, balancing and ancillary service markets, and networks to 2050", converted to GBP/MWh by dividing by generation over the same period, both in net present value terms (paraphrase). SRC-784 p.43 (PDF p.45): "The estimates show the wider system impact that a hypothetical small increment of a technology"; "distribution network impacts are not included"; "Wider system impacts are entirely system dependent"; "presented relative to the wider system impacts of a nuclear plant." SRC-784 p.44 (PDF p.46) (paraphrase): the levelised costs in the Section 7 tables assume maximum load factors with balancing charges stripped out to avoid double counting.
Basis: N/A (a statement of method and scope, not a cost figure); the report's GBP estimates are in 2018 real values (p.5).
Related records
- Answers question
- QST-021 not published in this release
Cite this
energyaperture.com/c/clm-1427
CLM-1427, Energy Aperture, as of 2020-08.
Connected records
Other published records linked to this one. A list, not a judgement.