Amber-advised INPP part of consortium selected as preferred bidder on Sizewell C

London, 22 July 2025 - Amber Infrastructure Group (‘Amber’) - part of Boyd Watterson Global Asset Management Group LLC - the specialist international investment manager and investment adviser to International Public Partnerships Limited (‘INPP’), is pleased to announce that INPP has committed c.£250 million to Sizewell C’s regulated company in return for a c.3.0% shareholding. The Nuclear Liabilities Fund is also committing c.£400 million to the Project, with Amber acting as its investment manager. Amber will exercise governance for and on behalf of both the Nuclear Liabilities Fund and INPP. Financial close and revenue commencement is expected in Q4 2025.

INPP intends to invest c.£50 million per annum over the next five years alongside financing form the UK Government, the Nuclear Liabilities Fund, La Caisse (previously CDPQ), EDF, and Centrica to finance the landmark construction, development and 60-year operations of a new nuclear plant capable of producing c.3.2GW of baseload low-carbon electricity to meet 7% of the UK’s forecast electricity needs (together, ‘the Project’).

Sizewell C’s financing was procured by the UK Government using the Regulated Asset Base (‘RAB’) model. Amber played an instrumental role to achieve a bespoke structuring of INPP’s investment in the Project. This includes predictable inflation-linked cash flows regulated by Ofgem and underpinned by critical infrastructure; a cash yield from day one of Sizewell C’s financial close, an opportunity for significant capital growth; an attractive, fixed rate of return during construction and early operations, no exposure to power price volatility; and enhanced investor protections.

In considering the opportunity to invest in Sizewell C and strengthening the merits of the investment case for INPP, the INPP Board has benefitted from both Amber’s heritage in market innovation, its ability to access rare greenfield infrastructure opportunities, and its close collaboration with the UK Government since 2016 in informing the design of a procurement method for new nuclear power that would be attractive to INPP’s investors. The UK Government and Ofgem have selected the RAB model to finance Sizewell C, with the licensing regime and contractual structure being adapted from Tideway, the 25km ‘super sewer’ sponsored by Amber and INPP in 2015, and successfully operational since 2025. 

Amber will exercise governance for and on behalf of both the Nuclear Liabilities Fund and INPP (together representing a c.7.5% initial shareholding). Amber secured strong governance rights for INPP, including a Board directorship at the Holding Company level and an observer role at the Generating Company, which holds the licence from Ofgem.

As a result of Amber’s work since responding to the nuclear RAB consultation in 2019, INPP will invest in Sizewell C alongside financial investors and operators who share a strong alignment of interests and relevant experience in the sector. Thanks to the adapted RAB model, INPP’s investment in Sizewell C will benefit from a UK Government Support Package (‘GSP’) and licence arrangements granted by Ofgem which provide, inter alia:

• Robust protections for investors allowable returns in the event of cost overruns and delays to construction, even in severe downside scenarios;
• Ringfence for consortium investors in Sizewell C from remote nuclear-specific risks, including decommissioning risks and any liabilities in the event of low-probability, high-impact incidents;
• Liquidity facility provided under the GSP to mitigate refinancing risk;
• Like-minded and aligned co-shareholders;
• Strong governance rights through the holding company Board directorship to be held by Amber and appropriate conflict of interest protections concerning the UK Government’s equity shareholding and debt interests.

Sizewell C is a landmark infrastructure investment critical to strengthening the UK’s energy security and meeting net zero targets. Once operational, Sizewell C is forecast to power the equivalent of approximately six million UK homes and enable the UK to produce home-grown, stable, and emissions-free baseload electricity for future generations. The Project will bolster the UK’s nuclear energy ecosystem, attracting and training world-class talent with the expectation of creating 10,000 new jobs at peak construction, thousands more in the nationwide supply chain, and 1,500 new apprenticeships.

As part of the UK Government’s Net Zero 2050 objectives, the UK has committed to deploying new nuclear capacity by 2050. Sizewell C is the first nuclear project to be procured under the RAB model. However, its design, construction, operations and financing adopt mature and proven approaches from nuclear power in the UK and globally, including:

• Mature, Standardised Design: over 80% of Sizewell C’s design for infrastructure built above ground level is fully replicated from Hinkley Point C . Sizewell C will also benefit from “as built” design, meaning the construction pathway benefits from a high degree of certainty; 
• Proven Technology: Sizewell C will use the most common reactor type in the world which accounts for two thirds of the nuclear reactors currently operable;
• Established Pre-Qualified Supply Chain: in replicating designs and borrowing lessons learned from Hinkley Point C, Sizewell C benefits from supply chain knowhow, knowledge sharing, and a highly-skilled workforce in nuclear and civil engineering pre-qualified to begin construction; 
• Outstanding Management Team: Sizewell C is led by an experienced executive management team and non-executive board, including Chair of the Board, John-Holland Kaye - former CEO of Heathrow Airport and non-Executive Director on Tideway; Julia Pyke, who has led Sizewell C’s development and has deep expertise in structuring major construction projects, and Nigel Cann who brings over four decades of experience in the nuclear industry in large-scale project management.

Amber is part of Boyd Watterson Global Asset Management Group LLC (‘Boyd’), a global diversified infrastructure, real estate and fixed income business with over $36 billion in assets under management and over 300 employees with offices in eight US cities and twelve countries.

Amber itself is a specialist international investment manager focused on investment, asset management and fund management. Amber currently manages or advises nine funds (two listed and seven private) with c.£5 billion in funds under management. With a presence across 12 countries, Amber manages 175 infrastructure investments representing total assets under management (‘AUM’) of £14 billion (c.$18 billion). Amber’s core business focuses on managing infrastructure assets across the public, transport, energy, digital and demographic infrastructure sectors internationally. Amber is headquartered in London with offices in Europe, North America, Australia and New Zealand. Amber employs over 180 professionals globally.