Third Quarter Update

26 November 2025

US Solar Fund PLC

("USF", or the "Company")

THIRD QUARTER UPDATE

US Solar Fund plc (LON:USF (USD)/USFP (GBP)), the renewable energy fund investing in utility-scale solar power plants across North America, is pleased to release its third quarter update for the period ended 30 September 2025.

Highlights for the quarter to 30 September 2025:

NAV update:

· USF's NAV for the period remained stable with an unaudited NAV as of 30 September 2025 of $198.3 million ($0.64 per share). This represents a decrease of approximately 1.1% from the audited NAV as of 30 June 2025

Dividend update:

· Dividend of 0.875 cents per Ordinary Share for Q3 2025 is to be paid by 29 December 2025, in line with the Company's revised dividend target of 3.5 cents per Ordinary Share

Portfolio performance:

· Generation by the Company's portfolio during the nine-month period to 30 September 2025 was 11.5% below forecast, with 0.5% attributable to weather and 11% attributable to technical (non-weather) factors

· Performance during the third quarter was impacted by lead time on parts and downtime of projects identified for capital initiatives as well as external factors outside of the Company's control including utility grid outages and site damage due to theft

· Additional inverter losses were avoided during the period with the ongoing implementation of the spare parts strategy

· Addressing unplanned outages continue to be the focal point as the Investment Manager progresses with certain capital initiatives and theft remediation

Post period end:

· Of the sites previously identified for capital investment initiatives, two have been completed

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For further information, please contact:

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 Company's investment objective is to provide investors with attractive and sustainable dividends with an element of capital growth by owning and operating solar power assets in the US.

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, all located in the United States.

Further information on the Company can be found on its website at www.ussolarfund.co.uk.

About Amber Infrastructure Group

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

Amber Infrastructure Group (Amber) is an international infrastructure specialist, focused on investment origination, development, asset management and in Europe, fund management. Amber's core business focuses on infrastructure assets across the public, transport, energy, digital and demographic infrastructure sectors that support the lives of people, homes and businesses internationally.

Among other funds, Amber advises International Public Partnerships, a FTSE 250-listed Company with a market cap of £2.2billion and 15-year track record of long-term investment in infrastructure assets globally. Amber is headquartered in London with offices in Europe, North America and Australia and employs c.180 infrastructure professionals. Amber has had a strategic partnership with Hunt Companies, Inc. in the US since 2015 and completed their previously announced strategic combination with Boyd Watterson in August 2024.

Learn more at www.amberinfrastructure.com.