Portrait of Joseph Duffy

Joseph Duffy : Senior Consultant

Joe is a member of Oxera’s Regulation and Analytics teams. He has worked across a range of regulated sectors and jurisdictions, including water, energy and transport. His work has spanned several areas including regulatory design, supporting companies in developing evidence to justify regulatory submissions and developing analytical models across a range of applications within regulation and competition economics.

Joe is a regular presenter at Oxera’s biannual Utility Regulation and Utility Finance courses, at which he has presented sessions on topics including outcomes, cost assessment, service quality mechanisms and incentives. He has presented and published papers in the transport and water sectors.

Joseph speaks English.

Tel: +44 (0) 1865 253224

Joseph's specialisms include:

professional experience

  • Ongoing work developing expert evidence as part of a litigation case for a European airport regarding a dispute relating to a CAPEX trigger in a concession contract (2020–)

  • Provided advice to an electricity transmission company in formulating its response to cost assessment in Ofgem’s draft determination—contributing towards achievement of a substantially better outcome at final determination stage (2020)

  • Provided support to Anglian Water on developing evidence and submissions on a range of regulatory issues as part of its appeal of Ofwat’s PR19 price review (2019–)

  • Regulatory advice to Highways England on regulatory strategy issues, including framework design, service quality and efficiency (2019–)

  • Developing a government sector policy for ports (airport and harbour) for an island economy, including specific policy recommendations and advice on a future framework for stakeholder engagement (2019–)

  • Provided regulatory advice to a European airport in developing its business plan for the next regulatory period (2019)


  • Duffy, J. and Horncastle, A. (forthcoming), ‘Benchmarking in the European water sector’, chapter in S.C. Ray, R. Chambers and S. Kumbhakar (eds), Handbook of Production Economics, vol. 2, Springer.

  • Duffy, J., Horncastle, A. and Kumbhakar, S. (2018), ‘Cost efficiency in the England and Wales water industry: looking ahead to PR19’, DEA40 conference

  • Duffy, J., Martin-Tonks, R. and Meaney A. (2015), ‘How Has the Change in the Industry Model Affected the GB Rail Sector?’, European Transport Conference 2015.


  • MPhil Economics, University of Cambridge

  • BSc Economics, University of Warwick

Latest Insights:  Joseph Duffy

9 minute read
On 13 December 2023, Ofgem published its Sector Specific Methodology Consultation (SSMC) for its forthcoming RIIO-3 price control for electricity transmission, gas transmission and gas distribution networks. Oxera summarises some…
16 minute read
On 7 July, Ofwat published its draft methodology for its next price review (PR24), setting out in detail how it plans to assess expenditure, financing costs, performance targets and incentives…
8 minute read
What were the root causes and costs of the recent supplier failures in the UK energy retail market? The Board at Ofgem (the energy regulator for Great Britain) asked Oxera…
10 minute read
In May 2021, Ofwat, the economic regulator of the water industry in England and Wales, set out its vision for the next price review (PR24). Key themes are long-term planning,…

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