Johannes Rittershausen

Chief Executive Officer

Johannes is responsible for strategic planning, business development, investor relations, and organizational stewardship. He is devoted to developing and executing the innovative business models that enable cost-effective energy storage projects.

He has 10 years of experience in the utility industry, including a 5-year career at Southern California Edison performing functions including wholesale electricity market procurement and corporate strategic planning.

Johannes holds a BA from Pomona College and an MA from Georgetown University.

Frank Genova

Chief Financial Officer + Chief Operating Officer

Frank is responsible for technology evaluation, asset development, project and corporate finance, and corporate M&A. Frank helped found Convergent after 6 years working in project development and finance with Fisher Brothers and Plaza Construction, focusing on renewable development, renewable integration, complex mechanical and electrical system integration, and corporate strategy. Frank holds a BA from Villanova University in Mechanical Engineering and an MBA in Finance, Phi Kappa Phi from Fordham University’s Graduate School of Business.

Chris Streeter

Chief Information Officer + Chief Risk Officer

Chris is responsible for the quantitative analysis of energy markets and grid infrastructure, regulatory and compliance activities, and the design, production, deployment, and maintenance of software systems to optimize storage asset operations and financial returns.

Prior to joining Convergent, Chris spent 8 years as a strategy consultant, both as an independent contractor and as a member of the firm AltshulerGray, LLC, focusing on complex data analysis and developing / implementing evaluation frameworks to meet profit maximization and compliance targets.

Chris graduated with honors from Harvard University with an A.B. in Biology.

Business Development

Toby Tiktinsky

Senior Vice President, Business Development

Toby is responsible for originating, negotiating, closing, and developing behind-the-meter projects with commercial and industrial clients, while supporting the firm’s overall business development strategy.

Toby comes to Convergent with 15 years of experience in project development, environmental policy and markets, and B2B sales and consulting. As Pakistan Country Director for EcoSecurities, Toby established the country’s first private carbon finance company and helped to finance distributed generation and energy efficiency projects. More recently, Toby started a renewable energy origination and brokerage platform where he partnered with leading solar developers to develop projects for retailers. Previously, Toby served as Director of Business Development for BrightFarms, a venture-backed start-up that adapted the power purchase agreement contracting model to finance and build controlled environment agriculture facilities.

Toby graduated with honors from the University of San Francisco and holds an MSc from the London School of Economics.

Derek Oosterman

Senior Vice President, Strategic Projects

Derek is responsible for all property-related aspects of Convergent’s business lines, including the identification, acquisition, development, and ongoing management of energy storage asset locations throughout North America including greenfields, brownfields, and commercial and industrial properties.

He has fifteen years of experience in the real estate sector, including extensive work in the acquisition, management, and disposition of commercial real estate debt and assets, with a focus on distress. He has advised builders, developers, investment managers and government entities on strategic land use decisions, with particular emphasis on mixed-use, urban/suburban, residential-led regeneration.

Derek holds a BA in Economics and International Relations from Pomona College and an MBA with emphasis in Finance and Real Estate from the UCLA Anderson School of Management.

Adam Green

Senior Vice President, Business Development

Adam is responsible for the team configuring, contracting, siting, permitting, and closing storage and solar projects on the utility side of the meter throughout North America.

Adam has over eight years of experience with storage and solar, and has developed hundreds of megawatts of projects in three continents, most recently as Director of Development at SolarReserve. His areas of expertise include real estate and land use, contracting, solar performance modeling, and local community relations. He has also written technical papers on the capabilities of solar and storage, and he holds two patents.

Adam graduated Phi Beta Kappa and Magna Cum Laude from Brown University with an honors concentration of his own design entitled “Rationality and Decision Making,” and received his MBA from the UCLA Anderson School of Management.

Tremor Temchin

Vice President, Business Development

Tremor is active in all phases of the project development cycle including opportunity identification, pre-development / construction, and the continued operations and maintenance of company assets.

Prior to joining Convergent, Tremor served as the Founder and Executive Director of the Rotary Pacific Water for Life Foundation, a non-governmental organization based in Fiji that builds healthier communities by providing sustainable access to safer drinking water and sanitation in the Pacific Island Nations. He also worked as a writer for various television series and assisted in the production of several feature films.

Tremor graduated with honors from Pomona College and holds an M.A. from the University of the South Pacific’s Pacific Centre for Environment and Sustainable Development.

John Markley

Vice President, Business Development

John is responsible for managing the development of energy projects, which includes site assessment, negotiating and transacting real estate agreements, originating energy contracts, and securing land use permits.

John comes to Convergent with 25+ years of investment and project management experience. Prior to joining Convergent, he was a managing director for a New York based private equity firm making investments in commercial and residential real estate, media, and energy sector services. His experience also includes work as a software developer, managing a wide variety of projects and teams.

John holds a BS in Computer Science from the University of Arizona.

Dave Wagner

Vice President, Business Development

Dave is responsible for originating, negotiating, closing and developing solar + storage projects.
Dave brings with him over 10 years of domestic and international utility-scale wind and solar
development experience. Prior to joining Convergent, Dave was with Apex Clean Energy and
SolarReserve where he managed the development of solar and wind projects throughout the U.S.,
Mexico, Central and South America, and the Caribbean. In all, Dave has managed the business
development, project initiation, acquisition, permitting and pre-construction process for over 1.5 GW of
wind and solar projects in a dozen countries throughout the world.

Dave holds a bachelor’s degree from the University of Illinois and resides in Des Moines, Iowa.

Fay Muhammad

Manager, Business Development

As Business Development Associate, Fay is responsible for supporting the sales cycle by generating new leads and building Convergent's behind-the-meter pipeline. Fay brings experience in the energy industry, spanning operations, risk, process improvement, and customer service.

Prior to joining Convergent, Fay worked with the Solar Loan Program at PSE&G, where she oversaw solar power and SREC production for over 900 residential customers in New Jersey. Previously, Fay served as an analyst for Constellation's Wholesale Operations group and an intern for the U.S. Energy Information Administration and Carbon Capital Management.

Fay holds a B.Sc. in Economics from the George Washington University and is currently earning her M.Sc. from the Norwegian School of Economics.

Peter Triassi

Manager, Business Development

Peter is responsible for commercial engagement and project contracting for Convergent’s commercial and industrial market segment.

Prior to joining Convergent, Peter served as Project Developer at Soventix Canada where he undertook origination and development activities on a 160 MW solar project portfolio. He supported the company in establishing a market presence in the province of Alberta, from initial site selection through RFP submission.

Peter holds a BA from Concordia University and an MSc Renewable Energy with distinction from the University of Reading.

Jim Tarpey

Project Executive

Jim is responsible for providing technical guidance and expert regulatory support on behalf of Convergent’s projects.

Jim comes to Convergent with 45 years of engineering and operations experience in gas and electric systems. At the end of 2011, he retired from Orange and Rockland Utilities (a Consolidated Edison company) as Vice President, Operations. He has been involved in corporate strategies, long range planning, service reliability initiatives, Smart Grid, emergency management, underground and overhead systems, integrated planning, project management, RTO participation, risk management and mitigation, demand side management, distributed generation, power quality, regulatory affairs, capital and O&M budgeting, cost containment, labor relations, safety, environmental, emerging technologies, and research and development.

Jim holds a BSEE from Worcester Polytechnic Institute and an MSEE from the New Jersey Institute of Technology and is a registered Professional Engineer.

Lawrence Tsang

Executive Advisor, Strategy

Lawrence works with the executive management team on strategic planning efforts. He is responsible for leading the execution of new business development initiatives and M&A activities to bring in new capabilities. He developed Convergent’s solar and storage business and continues to engage with utilities on project development.

Lawrence has over 10 years of experience in global energy and policy development and project finance. He was previously the Director of Global Strategy and Project Finance at OCI Solar Power where he successfully developed 450 MWs of solar in Texas. In this capacity, he led all capital market raises for projects and managed a global team to develop market analysis and business cases for high-potential growth opportunities in strategic markets (including Africa, China, Mexico, and India). Prior, he was a management and strategy consultant at Booz Allen Hamilton.

Lawrence holds a BSc. in Biology from Concordia University (Canada) and a Masters in Environmental Management from Harvard University.

Stephanie Reyes


Stephanie works on rotating projects and functions across Convergent, providing support in business development, customer engagement and marketing, project execution, asset management, financial optimization, and regulatory and policy development.

Stephanie holds a B.A in Latin American Studies from Pomona College.

Laura Meilander

Vice President, Business Development

Laura is responsible for originating, negotiating and closing energy storage projects.

She has over 15 years of experience in the utility and energy industry. She has worked in the power origination groups at Constellation Energy, Deutsche Bank and JP Morgan where she developed, negotiated, and executed structured wholesale energy transactions in PJM, MISO, ERCOT and the Northeast. She has also worked at Wood Mackenzie on the business development and research teams focusing on North American gas and power markets.

Laura holds a bachelor’s degree in chemical engineering from Rice University.

Michael J. Pristas

Vice President, Business Development

Mike is responsible for the grassroots development of energy storage and solar assets for electric co-ops and municipal utilities in the mid-Atlantic and Southeastern United States.

Mike has over 40 years of experience as a business development professional in the energy and power markets. Key roles include senior marketing and sales management positions with Schneider Electric, Cinergy, Power Measurement, and ABB. In addition, Mike was a founding member of Schneider’s highly successful PowerLogic business and started and developed NRTC’s Utility Solutions business, which serves electric co-ops.

Mike holds a BS in Business Management from Pennsylvania State University and performed MBA graduate work at George Washington University.

Andy Israelson

Vice President, Business Development

Andy is responsible spearheading the company’s M&A activities and crafting the firm’s strategy for winning RFP-based opportunities.

Andy has eight years of experience in various sub-sectors of the cleantech industry in finance, strategy, M&A, and project management positions. Prior to Convergent, Andy served as an Investments Analyst and a Development Manager at E.ON Climate and Renewables focusing on solar and storage technologies.

Andy holds a BS in Economics from Lehigh University and an MBA from the McCombs School of Business at The University of Texas at Austin.

Ruth Lind

Associate, Business Development

Ruth supports the sales team with originating behind-the-meter projects in the U.S. and Canada.
Prior to joining Convergent, Ruth worked at Piper Maddox a renewable energy driven recruitment company where she focused on new client engagement and headhunting activities. In particular, Ruth led the build-out of an energy storage industry team and has spent the past two years working within the sector. Given her background, she has already worked directly with many of the industry’s leading manufacturers and developers.

Ruth holds a BA (Honors) from the University of St Andrews in Scotland, UK.

Matt Duffy

Vice President, Business Development

Matt is responsible for originating, negotiating, and closing solar and storage projects. He has over 18 years of experience in the energy industry and spent the past 12 years focused on sustainable energy solutions.

Prior to his work in the energy sector, Matt had a 10-year career in the United States Marine Corps, serving as an infantry officer. Following his service, he worked with EDPR and BP Wind developing wind farms. At EDPR and BP Wind, Matt originated over $1Bn in wind energy contracts and developed over 1GW of wind projects/wind and storage projects.

Matt holds a BA from the College of the Holy Cross and an MBA from the Thunderbird School of International Management. Matt resides in Houston, TX.

Rick Cunningham

Vice President, Business Development

Rick is responsible for commercial engagement and project contracting of Convergent’s behind-the-meter projects with commercial and industrial clients.

Rick brings to Convergent over 20 years of experience in senior customer engagement roles across a diverse set of industries. Most recently he was Managing Director, Marketing and Sales for Cube Hydro Partners, LLC, an owner/operator of hydropower assets in North America. At Cube Hydro Rick led power marketing and sales initiatives and negotiated Power Purchase Agreements (PPAs) with commercial and industrial off-takers, government organizations and load serving entities. Rick also handled the monetization strategy for Renewable Energy Credits generated by Cube Hydro’s assets. Prior to Cube Hydro, Rick held Senior Vice President and Vice President sales and marketing leadership positions for companies in transportation solutions and telecommunications.

Rick holds a BA in Marketing from Michigan State University, has received training in Miller Heiman Strategic Selling, and holds an Information Technology Certification from Massachusetts Institute of Technology (MIT).

Project Development

Robin Gray

Senior Vice President, Engineering and Project Development

Robin is responsible for the development, design, construction, and operation of Convergent’s fully-integrated energy storage assets. Responsibilities include all aspects of project execution, including scheduling, budgeting, supplier management, permitting and interconnection coordination, as well as all aspects of on-site construction oversight and on-going maintenance requirements.

Robin came to Convergent with over 15 years of project execution experience including 10 years of direct utility experience with Consolidated Edison of NY. During Robin’s time with Con Edison, he was responsible for the execution of large scale capital projects including the design and project management of Con Edison’s first energy storage asset. At Con Edison, Robin was also responsible for the interconnection of customer-owned medium voltage substations and distributed generation (DG) equipment. As a subject matter expert for utility DG interconnections, Robin spent several years working for the IEEE 1547 Distributed Generation Interconnection Standards Working Group to standardize the interconnection process of DG assets.

Robin holds a Bachelor of Engineering (Hons) degree in Electrical and Electronic Engineering from the University of Manchester, Manchester, England, UK.

Derek Longo

Senior Project Manager, Project Development

Derek is responsible for all phases of project execution including technical coordination, supplier oversight and expediting, project budgeting, installation, and commissioning of project equipment. He also provides technical support to Convergent’s sales team in identifying and validating new project opportunities.

Derek has 8+ years of industrial project development and execution experience. Prior to joining Convergent, he served as a Field Engineer and Project Manager for FLSmidth Inc.’s Cement and Minerals Projects divisions. As a Field Engineer, he was stationed on site in order to troubleshoot the electro-mechanical hurdles during the installation and commissioning of company equipment. As a Project Manager, he managed budget and schedule from design to commissioning.

Derek graduated from Lehigh University with a BSc. in Mechanical Engineering.

Michel Menezes

Project Manager, Project Development

Michel is responsible for planning, executing, monitoring, controlling and closing all phases of the project’s lifecycle, including technical coordination, supplier oversight and expediting,
project budgeting, installation, and commissioning of project equipment. He also provides
technical support to Convergent’s sales team in identifying and validating new project opportunities.

Michel has 5+ years of construction project management. Prior to joining Convergent, he served as Project Manager for BGIS in Toronto, Canada managing electrical, mechanical, and energy efficiency projects. Previously, he worked in the shipbuilding industry, designing and providing technical support during the construction of petroleum tanker ships.

Michel is a certified Project Management Professional (PMP®) and holds a bachelor’s degree in Electrical Engineering from Federal University of Pernambuco in Recife, Brazil. He also has a Project Management certificate from Centennial College in Toronto, Canada.

Sonny Sok

Senior Field Technician

Mario Titolo

Project Manager, Project Development

Mario is responsible for managing all aspects of a project’s lifecycle from initial feasibility to installation and commissioning. He manages the project schedules, budgets, and all necessary permitting and approval processes. He also delivers technical support to the sales team helping to identify and qualify new opportunities.

Mario has over three years of renewable energy project engineering and development experience. Prior to joining Convergent, he served as a Project Engineer for Safari Energy developing commercial and industrial Solar PV projects. As a Project Engineer, he worked on producing detailed electrical engineering drawings and managed projects from design to commissioning.

Mario holds a BS in Mechanical and Aerospace Engineering from Cornell University. He is also a NABCEP Certified PV Installation Professional.

Tom Yeager

Project Manager, Project Development

Tom manages all aspects of project execution including technical coordination, supplier oversight, budgeting, construction, and commissioning. He also provides technical support to Convergent’s sales team in identifying and qualifying new project opportunities.

Tom’s background in engineering encompasses a variety experiences , including performing hazard analysis of radioactive waste for the DOE, operating a nuclear power plant, and delivering custom HVAC equipment.

Tom holds a BS in Nuclear Engineering from Rensselaer Polytechnic University.

Asset Management

David Nie

Senior Vice President, Asset Management

David is responsible for economic and financial evaluation of potential project opportunities, general quantitative sales support, wholesale and retail tariff evaluation, dispatch and algorithm development, and managing real-time operations.

Prior to joining Convergent, David worked at EnerNOC on the demand response team managing their portfolio in the PJM region. He has experience in day-to-day operations and long term strategy execution in capacity and energy markets.

David holds a BA from Dartmouth in Mathematics and Economics.

Avital Szulc

Vice President, Data Science and Machine Learning

Avital is responsible for leading the development and optimization of Convergent's real-time asset dispatch algorithms and their software integration.

Prior to leading Convergent's data science and machine learning efforts, Avital led the development of Convergent's Asset Management Platform, including its design, engineering, testing, and deployment.

Before joining Convergent, Avital worked as a product manager at A.F.Mensah, a distributed energy technology and development company. While at A.F. Mensah, Avital was responsible for the development of its asset management platform and prototyping of optimal asset dispatch algorithms.

Avital holds an M.S.E in Operations Research from Cornell University (Cornell Tech) and a B.S.E in Chemical Engineering from the University of Pennsylvania.

Allan Blanchard

Senior Analyst, Asset Management

Allan is responsible for the optimization and automation of real-time asset operations, dispatch and algorithm development, project and tariff evaluation, and quantitative sales support.

Prior to joining Convergent, Allan worked at Integrated Storage Technologies leading the analytics department with a focus on financial modelling and storage system optimizations that spanned a wide range of technologies and use cases. He has also spent five years working as a product engineer at Ambri, working to optimize and refine its storage technology. His work led to both patented and patent-pending innovations in battery chemistry and design.

Allan holds a BS in Material Science and Engineering from Massachusetts Institute of Technology.

Christian Gould


Christian works on rotating projects and functions across the company, providing support in business development, customer engagement and marketing, project execution, asset management, financial optimization, and regulatory and policy development.

Prior to joining Convergent, Christian interned at Sandia National Laboratories where he focused on modeling solar and geothermal heating projects. He also conducted undergraduate research on lithium-ion batteries and co-authored a research paper in the Journal of The Electrochemical Society.

Christian holds a BS in Chemical Engineering from Columbia University.

Surina Diddi

Associate, Asset Management

Surina is responsible for the economic and financial evaluation of potential growth opportunities, market analysis, real-time asset operations, and aspects of the investment pipeline.

Previously, Surina spent several years in energy finance as an Equity Research Associate at UBS and then in investment banking at Lazard / Scotiabank. In these roles, she conducted strategic analysis, modeling, and investment due diligence for projects across the power, infrastructure, and renewables space. She also worked for Agriculture Capital, a $900 million middle-market private equity fund focused on real asset investments in the agriculture and sustainability space.

Surina holds a BA in Economics from Wellesley College and has taken classes at MIT’s Sloan School of Management. Surina was an Energy Fellow at the Madeleine Albright Institute for Global Affairs, is a CFA Level II candidate, and speaks five languages.


Kate Siskel

Vice President, Marketing

Kate is responsible for sharing Convergent's story across multiple platforms in a dynamic, inspiring way.

Kate comes to Convergent with over a decade of marketing and communications experience and a passion for swaying hearts and minds through powerful storytelling. Most recently, she drove marketing strategies and influencer engagement to increase brand awareness at the national nonprofit the Alliance for a Healthier Generation. Prior, Kate owned all marketing and communications efforts at BrightFarms, an urban agriculture start-up. There, she led a team to rebrand the company and secured strategic national and local media placements that generated millions of impressions and directly impacted business development goals.

Kate holds a BA from Yale University and an MA from New York University.


Sumeet Sikka

Senior Vice President, Controller

Sumeet is responsible for establishing and executing policies and internal controls over Convergent’s accounting and financial procedures to safeguard the company’s assets as well as protect the integrity of its financial data. Responsibilities include overseeing all accounting operations including financial close, preparation of financial statements, treasury, internal management reporting, compliance, budgeting and project management.

Sumeet joined Convergent with over 20 years of experience across a broad range of accounting/finance areas including financial/management reporting, ERP implementation, compliance, audit and taxation. Prior to joining Convergent, Sumeet served as an Assistant Controller at SUEZ where he was instrumental in overall internal control management, optimization of information systems and financial reporting. Prior to that, he held several senior management positions including Director at National Grid.

Sumeet holds a bachelor’s degree in accounting from NJCU. He is a Certified Public Accountant (CPA) in the state of NY and is also a member of the American Institute of Certified Public Accountants.

Mario Acuna

Staff Accountant

As a Staff Accountant, Mario is responsible for the accounts payable cycle and the preparation of the annual audit.

Mario joined Convergent with over five years of accounting experience as an Accounts Payable Coordinator and Staff Accountant in the hospitality, public relations, and information services sectors. Mario has assisted in the monthly, quarterly, and yearly accounting close periods for accounts payable, accounts receivable, and general accounting. He also has experience with numerous ERP implementations.

Mario holds a BA in Business Administration with a concentration in Accounting & Management.

Career Opportunities

Senior Accountant
New York City
Project Manager - Site Specialist
New York Metropolitan Area
Business Development Associate
New York Metropolitan Area