Ameresco : Investor Day – RNG Plant Tour 11/2022

Investor Tour: Renewable Natural Gas (RNG) Plant

91st Avenue Wastewater Biogas-to-RNG Plant

Phoenix, AZ

November 15, 2022

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Forward Looking Statements

Any statements in this presentation about future expectations, plans and prospects for Ameresco, Inc., including statements about market conditions, pipeline and backlog, as well as estimated future revenues, net income, adjusted EBITDA, Non-GAAP EPS, gross margin, capital investments, other financial guidance, expected impacted of the Inflation Reduction

Act, other expectations for our RNG Assets business and other statements containing the words "projects," "believes," "antici pates," "plans," "expects," "will" and similar expressions, constitute forward-looking statements within the meaning of The Private Securities Litigation Reform Act of 1995. Actual results may differ materially from those indicated by such

forward looking statements as a result of various important factors, including the timing of, and ability to, enter into cont racts for awarded projects on the terms proposed or at all; the timing of work we do on projects where we recognize revenue on a percentage of completion basis, including the ability to perform under recently signed contracts without delay; demand for our energy efficiency and renewable energy solutions; our ability to complete and operate our projects on a profit able basis and as committed to our customers; our ability to arrange financing to fund our operations and projects and to comply with covenants in our existing debt agreements; changes in federal, state and local government policies and programs related to energy efficiency and renewable energy and the fiscal health of the government; the ability of customers to cancel or defer contracts included in our backlog; the effects of our acquisitions and joint ventures; seasonality in construction and in demand for our products and services; a customer's decision to delay our work on, or other risks involved with, a particular project; availability and cost of labor and equipment particularly given global supply chain chal lenges; our reliance on third parties for our construction and installation work; the addition of new customers or the loss of existing customers including our reliance on the agreement wi th SCE for a significant portion of our revenues in 2022; the impact from Covid-19 on our business; global supply chain challenges, component shortages and inflationary pressures; market pri ce of the Company's stock prevailing from time to time; the nature of other investment opportunities presented to the Company from time to time; the Company's cash flows from operations; cybersecurity incidents and breaches; and other factors discussed in our Annual Report on Form 10-K for the year ended December 31, 2021, filed with the U.S. Securities and Exchange Commission (SEC) on March 1, 2022, the Quarterly Report on Form 10-Q for the quarter ended March 31, 2022, filed with the SEC on May 3, 2022, and other SEC Filings . The forward-looking statements included in this presentation represent our views as of the date of this presentation. We anticipate that subsequent events and developments will cause our views to change. However, while we may elect to update these forward-looking statements at some point in the future, we specifically disclaim any obligation to do so. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this presentation.

Use of Non-GAAP Financial Measures

This presentation and the accompanying tables include references to adjusted EBITDA, which is a Non-GAAP financial measures. For a description of these Non-GAAP financial measures, including the reasons management uses this measure, please see the section in the back of this presentation titled "Non-GAAP Financial Measures". For a reconciliation of this Non-GAAP financial measure to the most directly comparable financial measure prepared in accordance with GAAP, please see t he tables at the end of our earnings materials.

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Welcome and Market Opportunity

Leila

Dillon

Senior Vice President,

Corporate Marketing &

Communications

Agenda

11:30am	Welcome and Market Opportunity - Leila Dillon
11:35am	Ameresco and Renewable Natural Gas (RNG) - Mike Bakas
	•	RNG 101
	•	Ameresco's Depth of Experience
	•	Intro to RFS and LCFS Programs
	•	Market Potential for Green Fuels
12:20pm	Impact of the IRA - Doran Hole
12:30pm	Market Validation - Josh Baribeau
12:40pm	Q&A

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The Climate Clock is Ticking, and It's Time for Action

Ameresco's advanced technology portfolio integrates a wide range of decarbonization solutions - from supply to demand, electric to thermal, intermittent to firm renewables

• Addressing the need for decarbonization is top priority
• Clean energy transition will require a holistic lens and variety of solutions for meaningful, long-lasting impact
• Market requirements & urgency are a catalyst for continued adoption of Ameresco's resilient, integrated solutions
• • Reduce demand / consumption through efficiency measures
  • Couple intermittent and firm renewable generation resources
  • Establish energy resilience to reduce climate change impacts
• This is a critical time of opportunity for Ameresco and our customers to establish decarbonization strategies and deliver results consistent with the Paris Agreement 1.5˚C target

Methane is ~25X more potent than

CO2, the reference gas for Global Warming; Methane reductions are key to preventing climate catastrophe.

Reductions can be achieved using solutions available in agriculture & waste sectors; A variety of feedstocks can produce RNG, a biogas upgraded for use in place of fossil natural gas.

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