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This announcement contains inside information for the purposes of Article 7 of the UK Market Abuse Regulation. Upon publication, this inside information is in the public domain.

17 August 2026

US SOLAR FUND PLC

(the 'Company')

Potential Portfolio Sale - Extension of Award Of Exclusivity

US Solar Fund plc (LON: USF (USD)/USFP (GBP)), the renewable energy fund investing in utility-scale solar power plants across North America, announces that, further to its announcement on 18 May 2026, it has agreed to extend the period of exclusivity in relation to the proposed sale of USF Holding Corp, the Company's subsidiary which holds its entire portfolio of solar generation assets. The extension is granted in order to finalise the tax analysis related to the transaction, negotiate definitive documentation and complete any outstanding confirmatory due diligence.

As previously announced, following the receipt by the Company of a non-binding letter of intent for the disposal of its portfolio (the "Potential Transaction"), the Board granted an exclusivity period of 90 days to a prospective buyer (the "Buyer"), subject to customary carve outs. To date, diligence by the Buyer has progressed materially including accommodating an extensive schedule of site visits. The Board has agreed to extend the exclusivity period by 60 days which will now expire on 16 October 2026. The Company will provide an update on the timetable related to the Potential Transaction as soon as practicable.

The Potential Transaction remains subject to completion of due diligence, the receipt of any regulatory approvals required in connection with the Potential Transaction and the negotiation of definitive legal documentation. The identity of the Buyer and further details of the Potential Transaction are not being made public at this time. While discussions are ongoing, there can be no certainty that a transaction will be agreed upon or as to the final terms of any such agreement. Should the Potential Transaction proceed, it is expected that it will be subject to a shareholder vote. The Board is committed to maximising value for shareholders and will continue to provide further updates, including engaging with shareholders when appropriate. 

ENDS

About US Solar Fund plc

US Solar Fund plc, established in 2019, listed on the premium segment of the London Stock Exchange in April 2019.

The solar power assets that the Company acquires or constructs are expected to have an asset life of at least 30 years and generate stable and uncorrelated cashflows by selling electricity to creditworthy offtakers under long-term power purchase agreements (or PPAs). The Company's portfolio currently consists of 41 operational solar projects with a total capacity of 443MWDC and a weighted average of 9.9 years PPA term remaining as at 31 December 2025, all located in the United States.

Further information on the Company can be found on its website: http://www.ussolarfund.co.uk.

About Amber Infrastructure Group

Amber Infrastructure Investment Advisor LLC, a member of the Amber Infrastructure Group, was appointed as the Company's Investment Manager on 1 December 2023.

Amber is part of Boyd Watterson Global Asset Management Group LLC, a global diversified infrastructure, real estate and fixed income business with over $39 billion in assets under management and over 300 employees with offices in eight US cities and eleven countries.

Amber itself is a specialist international investment manager focused on investment, asset management and fund management. Amber currently manages or advises nine funds and managed accounts (two listed and seven private) with c.£5 billion in funds under management. With a presence across 11 countries, Amber manages over 200 infrastructure investments representing total assets under management ('AUM') of £14 billion as at 31 December 2025. 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.

Further information on Amber can be found on its website: http://www.amberinfrastructure.com

Important information

This announcement is made without prejudice to ongoing discussions in respect of the Potential Transaction described herein, and the terms thereof. There can be no certainty that any transaction will proceed, nor as to the final terms or timing of any transaction.

As it is intended that the Potential Transaction will comprise the sale of the Company's portfolio of solar generation assets, the UK City Code on Takeovers and Mergers (the "Code") is not expected to apply. The receipt of the non-binding letter of intent and the agreement by the Board to grant (and extend) an exclusivity period does not constitute an offer for the purposes of the Code.

Nothing in this announcement shall form the basis of or constitute any offer or invitation to sell or issue, or any solicitation of any offer to purchase or subscribe for any shares or any other securities nor shall it (or any part of it) or the fact of its distribution, form the basis of, or be relied on in connection with, any contract therefor. None of the Company's shareholders should base any financial decision on this announcement.  Any shareholder action required in connection with the potential transaction will only be set out in documents sent to or made available to shareholders, and any decision made by such shareholders should be made solely and only on the basis of information provided in those documents.

A further announcement will be made in due course.

The person responsible for making this announcement on behalf of the Company is Ruth Wright (JTC (UK) Limited).