Re- design of electricity transmission charges
Submitting Institution
University of BirminghamUnit of Assessment
Economics and EconometricsSummary Impact Type
EconomicResearch Subject Area(s)
Mathematical Sciences: Applied Mathematics
Economics: Applied Economics, Econometrics
Summary of the impact
The energy regulator, Ofgem, drew on research from the University of
Birmingham when it instructed the electricity industry to re-design
transmission charges that recover £1.6 billion per year. This
instruction, issued in May 2012, was the culmination of Project TransmiT
which Ofgem launched in September 2010. As part of TransmiT, Ofgem
commissioned three teams of academics to consider whether changes to
transmission prices were desirable and, if so, to recommend changes. One
of these teams was from the Universities of Birmingham and Strathclyde.
The changes introduced by Ofgem — which aimed to send more accurate
signals of the cost of dealing with low-carbon electricity — were those
recommended by the Birmingham and Strathclyde team. As a consequence, the
research has fundamentally shaped a significant change to the future of
electricity pricing in Great Britain, affecting the costs incurred by
the industry and the payments made by every consumer in the country.
Underpinning research
Professor Richard Green was Professor of Energy Economics at the
University of Birmingham from 1 July 2005 to 31 August 2011. One strand of
his research concerned the best way to organise the electricity wholesale
market in which generators sell power to the retailers ("suppliers" in the
UK) who then sell it on to customers. One of the key challenges is that
the location of the generator determines whether or not its output can
safely be accepted onto the network (over-loading the lines can lead to a
nation-wide blackout in the event of a failure) and also affects the
proportion of the generated power that can be delivered to customers. A
market mechanism known as nodal pricing has been adopted in
several parts of the US to take account of these factors, allowing prices
to vary across the power network to reflect the true marginal cost of
meeting extra demand at each point. In Great Britain, most electricity
trades ignore the generator's location on the network, but National Grid,
the system operator, then has to adjust the output from particular
generators to ensure that the physical constraints are met. These trades
are limited to meeting those constraints and do not result in a fully
optimal solution.
The research published in output 1 (R1; 2007) asked how important the
failure to reach an optimal solution was. It used a techno-economic model
of generation and transmission in England and Wales to calculate the
dispatch of power stations, and the resulting prices, under different
pricing rules. These included the current system, the "optimal" solution
of nodal pricing, and hybrids under which either consumers or generators
faced regionally differentiated prices. The research found that the
welfare benefits from moving to the optimal nodal prices were equal to
about 1 per cent of the wholesale market's turnover, that these came
mostly from exposing consumers to the true marginal cost of their
consumption, and that there were significant inter-regional welfare gains
and losses. The benefits of giving generators alone a price signal were
small.
Interdisciplinary research with electrical engineers from Strathclyde
(R2; 2007) asked how sensitive the transmission charges used in Great
Britain would be to different scenarios for the future evolution of
electricity generation to 2020. The differences between scenarios were
relatively small.
Another strand of research looked at the challenges of integrating
renewables and the demands that this would place on the spot market
mechanisms. Output 3 (R3; 2008) compared the generic wholesale market
designs used in the US and in Europe, and concluded that the balance of
advantage was swinging towards the US design, based on nodal pricing.
Output 4 (R4; 2010) continued this work, quantifying the swings in demand
and possible constraints on the England-Scotland border that the market
would have to cope with in Great Britain.
The majority of the research was funded by the Engineering and Physical
Sciences Research Council, under two Supergen Grants (details below). The
Principal Investigator on both grants was Professor J McDonald (University
of Strathclyde); Professor Green was a co-investigator, and was a
workstream leader on the second project
References to the research
Research outputs:
R2) Ault, G.W., I.M. Elders and R.J. Green (2007) `Transmission use of
system charges under future GB power system scenarios', IEEE
Transactions on Power Systems, vol. 22, no. 4, pp.
1523-1531 [http://dx.doi.org/10.1109/TPWRS.2007.907128]
Grants:
(a) Green, R (PI) GR/s28082/01 SUPERGEN — Future Network Technologies,
Sponsor: Engineering and Physical Sciences Research Council. October 2003
— September 2007, £3,419m (UoB allocation £80k).
(b) Green, R (PI) EPSRC Project EP/E04011X/1 SUPERGEN 1 Renewal Coare
— Flexnet: Renewal of the SUPERGEN Consortium on Future Network
Technologies, Sponsor: Engineering and Physical Sciences Research
Council. October 2007 — March 2012, £6,876,795 (UoB allocation £336,845).
Details of the impact
The electricity industry in Great Britain is regulated by the Office of
Gas and Electricity Markets, Ofgem. Ofgem has to set limits on the overall
level of the prices charged for electricity transmission and distribution
to consumers, and to approve the methodology by which the particular
prices paid by each system user are set. Ofgem (or strictly speaking, its
governing Gas and Electricity Markets Authority) is also responsible for
approving or denying changes to the rules of the British Electricity
Transmission and Trading Arrangements, which interact with the prices set
by the transmission companies to determine the overall cost of buying
power.
Ofgem drew on research findings of the University of Birmingham when it
instructed the electricity industry to re-design transmission charges that
recover £1.6 billion per year. This is a very significant impact because
of the geographical structure of supply of and demand for electricity.
Electricity typically flows from the north to the south of Great Britain,
and the flows have been greatest at the times of maximum demand. To
reflect the costs that these flows impose, transmission tariffs have been
based on the capacity of generators and are higher for generators in the
north than in the south. This imposes relatively high costs (per unit of
output) on renewable generators in Scotland and northern England, which
generate less per unit of capacity than most other power stations,
potentially raising the subsidy they require to break even.
Ofgem started Project TransmiT in 2010 to review whether these charging
arrangements would remain fit for purpose as the proportion of low-carbon
generation increased through 2020 and beyond. There was extensive industry
consultation, and three teams of academics were engaged to consider
whether changes to transmission prices were desirable and, if so, to
recommend changes. A fourth team produced a report on whether transmission
prices should be used to promote low-carbon generation; another team
academic peer-reviewed the reports (source 3 below).
Professor Green was recruited as the sole economist in one of the teams
on account of his extensive reputation among policy-makers in this area
(source 4); for instance, he had been a Specialist Advisor to the House of
Commons Trade and Industry Committee for two reports in 2003 and 2004. On
this team, he worked alongside four engineers from the University of
Strathclyde. Professor Green played a crucial role in the team's work
through evaluating the economic impact of several alternative
methodologies considered in their report (source 1). The team recommended
improvements to the current charging methodology; in particular that
charges per unit of electricity generated should be introduced alongside
the existing (but reduced) charges for generating capacity. The intention
was to send an approximate signal of the costs imposed by distant
generators at off-peak times but to avoid proposing radical changes that
might not be politically implementable (such concerns were discussed in R3
above). The other two academic reports proposed the radical change of
introducing a system of nodal pricing as used in the US electricity
markets (source 2, which includes references to R1 above). All the draft
reports were presented to Ofgem at a meeting in March 2011 and published
after responding to feedback from the regulator.
The regulator rejected nodal pricing as it would have involved changes to
energy trading as well as to transmission pricing (source 5). Instead, it
favoured the approach of improving the current system that was recommended
by the Birmingham-Strathclyde team (source 6). Following further analysis,
National Grid has now been directed to develop charging proposals along
these lines (source 7). This includes explicit consideration of charges
per unit of output (as recommended in source 1); much of the industry
analysis had been of charges per MW of capacity that would be linked to
the generator's load factor, and hence mathematically equivalent to
charges per unit of output.
The research has thus fundamentally shaped a significant change to the
future of electricity pricing in Great Britain, affecting the costs
incurred by the industry and the payments made by every consumer in the
country. These "Transmission Network Use of System" charges amounted to
£1.58 billion in 2009/10 (source 1, pp 23-24). Ofgem are still working to
quantify the benefits from the changes, but their broad conclusion is that
"cost reflectivity drives more efficient decisions by market participants
and policy makers which creates value for consumers" (source 6, page 5);
this is the key theme which was expanded and quantified in the research
presented in section 2 of this case study.
Sources to corroborate the impact
- Bell, K, R.J. Green, I. Kockar, G. Ault and J. McDonald (2011) Academic
Review of Transmission Charging Arrangements — Universities of
Strathclyde and Birmingham Academic Report Commissioned by
Ofgemhttp://www.ofgem.gov.uk/Networks/Trans/PT/WF/Documents1/Project_TransmiT_final%20report_Strath_Birm.pdf
- Newbery, D. (2011) High level principles for guiding GB
transmission charging and some of the practical problems of transition
to an enduring regime Academic Report Commissioned by Ofgem http://www.ofgem.gov.uk/Networks/Trans/PT/WF/Documents1/2011_April_22_David%20Newbery%20Report.pdf
- Ekins, P. (2011) Project TransmiT — A Peer Review of Commissioned
Academic Analysis Peer Review Commissioned by
Ofgemhttp://www.ofgem.gov.uk/Networks/Trans/PT/WF/Documents1/Paul%20Ekins%20final%20report.pdf
- Corroborating statement from Senior Partner, Smarter Grids and
Transmission: Ofgem, 12 March 2013 held by the University
- Ofgem (2011a) Project TransmiT: approach to electricity
transmission charging work, Reference Number 73/11
http://www.ofgem.gov.uk/Networks/Trans/PT/Documents1/110527_TransmiT_charging_letter.pdf
- Ofgem (2011b) Electricity transmission charging: assessment of
options for change reference 188/11
http://www.ofgem.gov.uk/Networks/Trans/PT/Documents1/Project%20TransmiT%20Dec11.pdf
- Ofgem (2012) Electricity transmission charging arrangements:
Significant Code Review conclusions reference 65/12
http://www.ofgem.gov.uk/Networks/Trans/PT/Documents1/TransmiT%20SCR%20conclusion%20document.pdf