Orion Energy : 2023 Proxy Statement

June 30, 2023

Dear Fellow Shareholders:

Thank you for your investment in Orion Energy Systems, Inc. and for the confidence you have placed in the Board of Directors and the Orion team. In fiscal 2023, we made substantial progress advancing our mission of helping customers achieve their business and environmental goals.

We continued our expansion into electrical maintenance solutions and entered the rapidly growing market for commercial electric vehicle charging station solutions. We are building out both of these businesses nation- ally, to complement our commercial and industrial LED lighting solution capabilities. Our expanded suite of complementary product and service offerings, our unique technical and turnkey project expertise, and our leading product and service quality truly differentiate Orion and support our mission and long-term opportunities.

Fiscal 2023 highlights include:

EV Charging Solutions. Following its acquisition in October 2022, the Voltrek business surpassed our expectations, delivering revenue of $6.3M in the second half of FY 2023. As we work this year to build out our reach across the U.S, we anticipate substantial growth in our EV charging division's revenue and profits over the coming years, as it provides charging infrastructure supporting the rapid adoption of electric vehicles.

Maintenance Services. Maintenance services revenue rose 150% to $14.6M in FY 2023 compared to FY 2022, benefitting from a full year's contribution from our new Stay-Lite Lighting team as well as organic growth. Like EV charging solutions, maintenance services enable us to offer an expanded suite of complementary solutions to our customers and partners. Importantly, maintenance also provides a growing base of recurring revenue that complements the project nature of LED lighting and EV charging deployments.

Financial Results and Position. As anticipated, due primarily to the expected lower level of revenue from our largest customer and a global online retailer, as well as on certain large LED project delays, our FY 2023 revenue declined to $77.4M from $124.4M in FY 2022. Excluding our largest customer and the global online retailer, Orion was successful in growing revenue by 11% over FY 2022, reflecting the increasing diversity of our customer base and the growing breadth of our operations. We believe the strategic changes we have made to the business positions us well for the coming year and going forward.

Importantly, Orion entered FY 2024 with $24.9M of working capital, including $16.0M of cash and cash equivalents and $18.2M of inventory. We believe this provides a solid financial base to fund our growth goals for the current year, and to support our efforts in advancing our long-term environmental, social and corporate governance objectives.

We encourage you to attend our 2023 Annual Meeting of Shareholders that will be held online at http:// www.virtualshareholdermeeting.com/OESX2023 on Thursday, August 10, 2023, at 1:00 p.m. Central Time. A replay of our Annual Meeting of Shareholders will also be available on our website during the month of August.

Sincerely,

Michael H. Jenkins Chief Executive Officer

Orion Energy Systems, Inc.

2210 Woodland Drive

Manitowoc, Wisconsin 54220

[phone]

NOTICE OF 2023 ANNUAL MEETING OF SHAREHOLDERS

To the Shareholders of Orion Energy Systems, Inc.:

Our 2023 Annual Meeting of Shareholders will be held on Thursday, August 10, 2023, at 1:00 p.m., Central Time, online at www.virtualshareholdermeeting.com/OESX2023. You will be able to listen to the annual meeting live, submit questions and vote online. A replay of the annual meeting will be available on our website during the month of August.

At the annual meeting, as we describe in the accompanying proxy statement, we will ask you to vote on the following matters:

1. the election of one nominee named in the attached proxy statement as a Class I director to serve for a term expiring at the 2026 annual meeting of shareholders and one nominee named in the attached proxy statement as a Class II director to serve for a term expiring at the 2024 annual meeting of shareholders, in each case until his or her successor has been duly elected and qualified;
2. an advisory vote to approve the compensation of our named executive officers as disclosed in the accompanying proxy statement;
3. an advisory vote on the frequency of future advisory shareholder votes on the compensation of our named executive offi- cers;
4. the approval of the 2016 Orion Energy Systems, Inc. Omnibus Incentive Plan, as amended and restated (the "Amended 2016 Plan");
5. the ratification of BDO USA, LLP to serve as our independent registered public accounting firm for our fiscal year 2024; and
6. such other business as may properly come before the annual meeting, or any adjournment or postponement thereof.

You are entitled to vote at the annual meeting only if you were a shareholder of record at the close of business on June 14, 2023. A proxy statement and proxy card are enclosed.

In order to provide our shareholders a more convenient, cost-effective method of attending, we have elected to hold our annual meeting via remote communication. You may attend the virtual annual meeting and vote your shares during the meeting by visiting our annual meeting website at www.virtualshareholdermeeting.com/OESX2023. You are entitled to participate in and submit questions in writing during the annual meeting if you were a shareholder as of the close of business on June 14, 2023. To be admitted to the annual meeting at www.virtualshareholdermeeting.com/OESX2023, you will need the 16-digit control number included on your notice, your proxy card or the instructions that accompanied your proxy materials. The annual meeting will begin promptly at 1:00 p.m., Central Time. Online check-in will begin at 12:45 p.m., Central Time. Please allow ample time for the online check-in proce- dures. If you have difficulty accessing the virtual annual meeting, please call the technical support number that will be posted on the virtual annual meeting log in page for assistance. We will have personnel available to assist you. If you hold shares through a bank, broker or other nominee, you will need to contact such bank, broker or other nominee for assistance with your 16-digit control num- ber.

Whether or not you expect to attend the annual meeting, it is important that you promptly complete, sign, date and submit your proxy card via internet, telephone or mail in accordance with its instructions so that you may vote your shares. If you hold your shares in a brokerage account, you should be aware that, if you do not instruct your broker how to vote, your broker will not be permitted to vote your shares for the election of directors, on the advisory vote to approve the compensation of our named executive officers, on the advisory vote on the frequency of future advisory shareholder votes on the compensation of our named executive officers or the approval of the Amended 2016 Plan. Therefore, you must affirmatively take action to vote your shares at our annual meeting. If you do not, your shares will not be voted on these items.

By order of the Board of Directors:

Michael H. Jenkins

Chief Executive Officer

Manitowoc, Wisconsin

June 30, 2023

Important Notice Regarding the Availability of Proxy Materials for the Shareholder Meeting To Be Held on August 10, 2023. Our proxy statement for our 2023 Annual Meeting of Shareholders and our 2023 Annual Report to Shareholders are available at www.proxyvote.com.

Our Annual Report on Form 10-K is enclosed with this notice and proxy statement for shareholders who have elected to receive paper copies of our proxy materials.

PROXY STATEMENT

FOR THE 2023 ANNUAL MEETING OF SHAREHOLDERS

To be Held August 10, 2023

We are providing these proxy materials to you because our board of directors is soliciting proxies for use at our 2023 Annual Meeting of Shareholders to be held online on Thursday, August 10, 2023, at 1:00 p.m., Central Time, and at any adjournment or postponement thereof (which we refer to collectively as our "annual meeting"), for the purposes set forth in the attached Notice of 2023 Annual Meeting of Shareholders and as described herein. We either (i) mailed you a notice of internet availability of our proxy materials on or before June 30, 2023 notifying each shareholder entitled to vote at the annual meeting how to vote and how to electronically access a copy of this proxy statement and form or proxy or (ii) mailed you a printed copy of such proxy materials and a proxy card in paper format.

In order to provide our shareholders a more convenient, cost-effective method of attending, we have elected to hold our annual meeting via remote communication. You may attend the virtual annual meeting and vote your shares during the meeting by visiting our annual meeting website at www.virtualshareholdermeeting.com/ OESX2023. A replay will be available on our website during the month of August. You are entitled to participate in the annual meeting if you were a shareholder as of the close of business on June 14, 2023. To be admitted to the annual meeting at www.virtualshareholdermeeting.com/OESX2023, you will need the 16-digit control number included on your notice, your proxy card or the instructions that accompanied your proxy materials. The annual meeting will begin promptly at 1:00 p.m., Central Time. Online check-in will begin at 12:45 p.m., Central Time. Please allow ample time for the online check-in procedures. If you have difficulty accessing the virtual annual meeting, please call the technical support number that will be posted on the virtual annual meeting log in page for assistance. We will have personnel available to assist you. If you hold shares through a bank, broker or other nominee, you will need to contact such bank, broker or other nominee for assistance with your 16-digit control number.

This year's shareholder question and answer session will include appropriate questions submitted in advance of, and appropriate questions submitted live during, the annual meeting. You may submit an appropriate question in advance of the meeting at www.proxyvote.com after logging in with your 16-digit control number. Appropriate questions may be submitted during the annual meeting through www.virtualshareholdermeeting.com/ OESX2023. We expect to respond to appropriate questions during the annual meeting, and may also respond to appropriate questions on an individual basis or by posting answers on our investor relations website after the meeting.

Consistent with prior years, we are using the "notice and access" system adopted by the SEC relating to the delivery of our proxy materials over the internet. The SEC's notice and access rules allow us to deliver our proxy materials to our shareholders by posting the materials on an internet website, notifying shareholders of the availability of our proxy materials on the internet and sending paper copies of our proxy materials upon shareholder request. We believe that the notice and access rules allow us to use internet technology that many shareholders prefer, continue to provide our shareholders with the information that they need and, at the same time, ensure more prompt delivery of our proxy materials. The notice and access rules also lower our cost of printing and delivering our proxy materials and minimize the environmental impact of printing paper copies.

As a result, we mailed to many of our shareholders a notice of internet availability of our proxy materials instead of a paper copy of our proxy materials. Shareholders who received the notice will have the ability to access our proxy materials over the internet and to request a paper copy of our proxy materials by mail, by e-mail or by telephone. Instructions on how to access our proxy materials over the internet or to request a paper copy may be found on the notice. In addition, the notice contains instructions on how shareholders may request our

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proxy materials in printed form by mail or electronically by e-mail on an ongoing basis. The notice of internet availability of our proxy materials also serves as a notice of meeting.

Execution of a proxy will not affect your right to attend and vote at the annual meeting virtually, nor will your presence revoke a previously submitted proxy. You may revoke a previously submitted proxy at any time before the annual meeting by giving written notice of your intention to revoke the proxy to our board secretary or by attending the annual meeting virtually and voting at the annual meeting online. Unless revoked, the shares represented by proxies received by our board of directors will be voted at the annual meeting in accordance with the instructions thereon. If no instructions are specified on a proxy, the votes represented thereby will be voted:

1. for the board's director nominees set forth below; (2) for the advisory vote to approve the compensation of our named executive officers as disclosed in the Compensation Discussion and Analysis section and the execu- tive compensation tables set forth below in this proxy statement; (3) for holding the advisory vote on the compensation of our named executive officers every year; (4) for the approval of the 2016 Orion Energy Sys- tems, Inc. Omnibus Incentive Plan, as amended and restated (the "Amended 2016 Plan"); (5) for the ratification of BDO USA, LLP to serve as our independent registered public accounting firm for our fiscal year 2024; and

1. on such other matters that may properly come before the annual meeting in accordance with the best judg- ment of the persons named as proxies. Our board of directors has designated Michael H. Jenkins and J. Per Bro- din, and each or either of them, as proxies to vote the shares of our common stock solicited on its behalf.

IMPORTANT: If you hold your shares in a brokerage account, you should be aware that, if you do not instruct your broker how to vote, your broker will not be permitted to vote your shares for the election of directors, on the advisory vote to approve the compensation of our named executive officers, on the advisory vote on the frequency of future advisory shareholder votes on the compensation of our named executive officers or the approval of the Amended 2016 Plan. Therefore, you must affirmatively take action to vote your shares at our annual meeting. If you do not, your shares will not be voted on these items.

The nominees receiving the highest vote totals of the eligible shares of our common stock, no par value per share ("Common Stock"), will be elected as a director. With regard to the election of directors, votes may be cast in favor or withheld; votes that are withheld will be excluded entirely from the vote and will have no effect. The advisory vote to approve the compensation of our named executive officers, the approval of the Amended 2016 Plan and the appointment of BDO USA, LLP to serve as our independent registered public accounting firm for our fiscal year 2024 will be approved if the votes cast in favor of approval exceed the votes cast against approval. The frequency of the advisory vote on the compensation of our named executive officers receiving the greatest number of votes cast in favor of such frequency, whether every year, every two years or every three years, will be the frequency of the advisory vote on executive compensation that shareholders are deemed to have approved. Abstentions and broker non-votes will be counted for purposes of determining the presence of a quorum but will be disregarded in the calculation of votes cast.

Only holders of record of shares of our Common Stock as of the close of business on June 14, 2023 (the "Record Date") are entitled to vote at the annual meeting. As of the Record Date, we had 32,501,846 shares of Common Stock outstanding and entitled to vote. The record holder of each share of Common Stock outstanding on the Record Date is entitled to one vote per share on each matter submitted for shareholder consideration at the annual meeting. In order for us to validly transact business at the annual meeting, we must have a quorum pres- ent. A majority of the votes of the shares of Common Stock entitled to be cast, or shares representing at least 16,250,924 votes, will represent a quorum for the purposes of the annual meeting.

WE INTEND TO BEGIN MAKING THIS PROXY STATEMENT AND THE NOTICE OF INTERNET AVAILABILITY OF PROXY MATERIALS AVAILABLE TO SHAREHOLDERS ON OR ABOUT JUNE 30, 2023.

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TRIBUTE TO MICHAEL W. ALTSCHAEFL

Michael W. Altschaefl has served on our board since October 2009 and served as our board chair from August 2016 to August 2022 and our chief executive officer from May 2017 to November 2022. Mr. Altschaefl is retiring from our board at the annual meeting. As a result, we want to formally extend our thanks and gratitude to Mr. Altschaefl for his years of dedicated service and contributions to our company, our board of directors and our shareholders. We extend to Mr. Altschaefl our sincere appreciation for his valued service, guidance, advice and dedication to our company and we all wish him the very best in his future endeavors.

TRIBUTE TO MARK C. WILLIAMSON

Mark C. Williamson served on our board from April 2009 until his retirement from our board in November 2022 and was our lead independent director from October 2009 through May 2013. We want to formally extend our thanks and gratitude to Mr. Williamson for his years of dedicated service and contributions to our company, our board of directors and our shareholders. We extend to Mr. Williamson our sincere appreciation for his valued service, guidance, advice and dedication to our company and we all wish him the very best in his future endeavors.

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