Our Team

Our team brings over 250 years of collective industry experience, with more than 1GW of renewable projects developed across the United States.

We have built a company with a wealth of experience and knowledge by bringing together successful energy developers from all over the world with veteran financial and legal experts. We believe that Onyx is the hardest working team in the industry with one clear goal - bringing safe, sustainable energy to our clients.

Matthew Rosenblum

Chief Executive Officer

Matthew Rosenblum, Founder and CEO, has more than 20 years of investment and trading experience. Previously, at Solops Matt was the largest producer and trader of Class 3 RECs in Connecticut and has personally conducted over 80 million dollars in REC transactions. Matt formed Onyx in partnership with Blackstone around his core operating team at Solops, LLC. Solops was formed by Matt to pursue C&I solar power development. Under Matt’s leadership, Solops built a portfolio of solar systems in partnership with local utilities, construction firms and off-takers, and became a significant producer and trader of renewable energy certificates. Prior to Solops, Matt was the Chief Executive Officer of Neuwing Energy, a leading proprietary trader in carbon related credits and provider of commercial energy strategies that focus on financial performance and environmental responsibility. Fortune 100 companies would engage Neuwing to monetize the environmental incentives including rebates, tax credits, carbon credits, and renewable energy certificates.Prior to his experience in the solar and energy industry, Matt also served in management positions at Hambrecht & Quist. He managed public investing of a $5 billion dollar fund and served as the relationship manager for KKR and Wall Street. During the acquisition of TXU (the largest utility takeover in US history) Matt was in charge of the analysis and compilation of programs for rebates and renewable energy certificates. He was the youngest Managing Director in history of Hambrecht & Quist and during the takeover of Hambrecht & Quist by JP Morgan was in charge of integrating the NASDAQ desk. Matt majored in Finance at the University of South Florida.

Ja Kao


Ja Kao, President, has over 15 years of finance and legal experience, as an investment banker and tax lawyer, structuring and placing complex financial instruments and structuring and executing M&A transactions across sectors, including financial services, media, telecom, energy (both traditional and renewable), consumer products and industrials. Prior to joining Onyx, Ja worked at The Blackstone Group, where she was a Managing Director on the Structured Solutions team of Blackstone Advisory Partners. While at Blackstone, she led the renewable energy investment banking practice, covering wind, solar and other technology companies. Ja structured multiple tax equity financing transactions for solar and wind projects. Prior to The Blackstone Group, Ja was a tax associate at the law firm of Shearman & Sterling, LLP in New York and worked on complex M&A, capital markets, cross-border finance and private client matters. Ja received a JD, cum laude, from Georgetown University Law Center and a BA with a major in Economics from Brandeis University. Ja serves as Chairman of the Board of Assessment Review for the town of Pound Ridge, NY and serves on the Board of Directors and Treasurer for the not-for-profit group, Internationals Network for Public Schools.

Ryan Marrone

Chief Legal Officer

Ryan A. Marrone, Co-Founder and Chief Legal Officer, has almost two decades of experience representing private and public companies including several Fortune 100. Ryan has led the development of over 320 MWs of commercial and industrial solar installations and closed on project financings totaling in excess of $1 Billion. Ryan was a co-founder of Solops, LLC and a member of the leadership team where he was Chief Operating Officer and General Counsel. Prior to Solops, Ryan practiced law with a concentration in general corporate, renewable energy, finance and real estate and served as General Counsel for Heller Industrial Parks. Ryan received a BA in English and Political Science from Seton Hall University and a JD from Widener University. Ryan serves on the Board of Directors of the YMCA - Hamilton and the Executive Compliance Board of RWJ University Hospital-Hamilton.

Matt West

Chief Construction Officer

Matt West, Chief Construction Officer, has 12 years’ experience in the real estate development and construction industry most notably in solar and wind. He has developed and constructed over 100 megawatts of renewable energy projects domestically and internationally. Matt specializes in all aspects of renewable energy project management, from feasibility to commissioning and is also an Accredited Professional in Leadership in Energy and Environmental Design (LEED) with emphasis on Building Design and Construction. Prior to joining Onyx, Matt served as the Executive Vice President of Construction for Solops and a Project Manager for Lanco Solar International and Alteris Renewables, one of the largest design-build renewable energy companies in the Northeast.