Canadian Solar's CSI Energy Storage Selected to Provide 40 MWh of Battery Energy Storage System to Unibal in the UK

GUELPH,ON,June 8,2023 --Canadian Solar Inc. (the "Company" or "Canadian Solar") (NASDAQ: CSIQ)today announced that CSI Energy Storage,which is part of its majority-owned subsidiaryCSI Solar Co.,Ltd.("CSI Solar"),has entered into a supply agreement with Unibal,a joint venture between Union Group and Capbal Limited,to deliver battery storage systems for two projects totaling 40 MWh in the United Kingdom. The projects are expected to reach commercial operation in Q1 2024.

The battery storage market in the UK has experienced significant growth and holds immense potential for supporting the country's transition to a low-carbon future and the UK Government's net-zero targets by 2050. These projects will further contribute to the seamless integration of renewable energy sources,enabling grid operators to efficiently balance supply and demand,and ultimately enhance the stability and reliability of the grid.

Dr.Shawn Qu,Chairman and CEO ofCanadian Solar,declared:"Leading renewable energy companies across the world,including Unibal,trust CSI Energy Storage to provide best-in-class energy storage systems. The UK is a major market for energy storage,and CSI Energy Storage is proud to grow our work there through this partnership."

Unibal Energy Limited is a UK based company focused on acquisition,origination,construction and operation of renewable generation and energy storage assets across the UK. CSI Energy Storage will deliver its SolBank battery energy storage systems and provide the full integration and commissioning services. CSI Energy Storage has also secured the long-term service agreements for the projects.

David Fyffe,Chairman of Unibal,stated "we wish to congratulate the CSI team on bringing such an impressive BESS offering to market. Our agreement provides a robust platform upon which to construct and operate BESS assets at significant scale."

CSI Energy Storage now has executed agreements to deliver 779 MWh of energy storage solutions to projects throughout the United Kingdom.CSI Energy Storage has deployed around 2.7 GWh of battery energy storage solutions to date acrossthe United States,Canada,theUnited Kingdom,andChina. As ofMarch 31,2023,CSI Energy Storage's total pipeline has reached nearly 22.8 GWh.

AboutCanadian Solar Inc.

Canadian Solar was founded in 2001 in Canada and is one of the world's largest solar technology and renewable energy companies. It is a leading manufacturer of solar photovoltaic modules,provider of solar energy and battery storage solutions,and developer of utility-scale solar power and battery storage projects with a geographically diversified pipeline in various stages of development. Over the past 22 years,Canadian Solar has successfully delivered around 94 GW of premium-quality,solar photovoltaic modules to customers across the world. Likewise,since entering the project development business in 2010,Canadian Solar has developed,built and connected over 8.8 GWp in over 20 countries across the world. Currently,the Company has approximately 609 MWp of projects in operation,6.9 GWp of projects under construction or in backlog (late-stage),and an additional 17.7 GWp of projects in advanced and early-stage pipeline. Canadian Solar is one of the most bankable companies in the solar and renewable energy industry,having been publicly listed on the NASDAQ since 2006.For additional information about the Company,follow Canadian Solar onLinkedInor visitwww.canadiansolar.com.

Safe Harbor/Forward-Looking Statements

Certain statements in this press release are forward-looking statements that involve a number of risks and uncertainties that could cause actual results to differ materially. These statements are made under the "Safe Harbor" provisions of theU.S.Private Securities Litigation Reform Act of 1995. In some cases,you can identify forward-looking statements by such terms as "believes," "expects," "anticipates," "intends," "estimates," the negative of these terms,or other comparable terminology. Factors that could cause actual results to differ include general business,regulatory and economic conditions and the state of the solar and battery storage market and industry; geopolitical tensions and conflicts,including impasses,sanctions and export controls; volatility,uncertainty,delays and disruptions related to the COVID-19 pandemic; supply chain disruptions; governmental support for the deployment of solar power; future available supplies of high-purity silicon; demand for end-use products by consumers and inventory levels of such products in the supply chain; changes in demand from significant customers; changes in demand from major markets,such asJapan,theU.S.,China,BrazilandEurope; changes in effective tax rates; changes in customer order patterns; changes in product mix; changes in corporate responsibility,especially environmental,social and governance ("ESG") requirements; capacity utilization; level of competition; pricing pressure and declines in or failure to timely adjust average selling prices; delays in new product introduction; delays in utility-scale project approval process; delays in utility-scale project construction; delays in the completion of project sales; continued success in technological innovations and delivery of products with the features that customers demand; shortage in supply of materials or capacity requirements; availability of financing; exchange and inflation rate fluctuations; uncertainties related to theCSI Solarcarve-out listing; litigation and other risks as described in the Company's filings with theSecurities and Exchange Commission,including its annual report on Form 20-F filed onApril 18,2023. Although the Company believes that the expectations reflected in the forward-looking statements are reasonable,it cannot guarantee future results,level of activity,performance,or achievements. Investors should not place undue reliance on these forward-looking statements. All information provided in this press release is as of today's date,unless otherwise stated,andCanadian Solarundertakes no duty to update such information,except as required under applicable law.

CANADIAN SOLAR INC.INVESTOR RELATIONS CONTACTS

Isabel Zhang

Investor Relations

Canadian Solar Inc.

investor@canadiansolar.com

David Pasquale

Global IR Partners

914-337-8801

csiq@globalirpartners.com

CSI ENERGY STORAGE MEDIA INQUIRIES

Ally Copple

Innovant Public Relations

713-201-8800

Ally@InnovantPR.com