Who We Are
Meet Our Team

Dr. Philipp Herzog, Chief Executive Officer at CollectiveSun®, LLC, is an experienced management consultant to leading international clients in areas such as strategy, finance, and development of emerging PV technologies. His prior clients include Bayer AG, Škoda Auto a.s., and Evonik Industries. Philipp holds a PhD and Master’s degree in Business Administration from the University of Münster, Germany, and has developed Sunforce’s unique multi-layer software tool that can analyze renewable energy projects from various perspectives to provide different investor types and stakeholders (e.g. tax equity investors or sponsor equity investor) with specific information (return, payback, risk etc.) relating to their investment.

Matthew Brennan is the VP of Sales at CollectiveSun®, LLC where he manages all aspects of installer and customer relationships, sales and project development. Matt has extensive experience in commercial solar sales, nonprofit solar financing and project management. Prior to CollectiveSun, he worked as an industrial engineer for a network equipment manufacturer, a sales engineer for electronic equipment manufacturers and an operations manager for an industry-leading mechanical engineering magazine. Matt enjoys working with nonprofit executives and solar professionals alike to help bring clean energy to the nation’s nonprofits and forward the decarbonization of the grid. Matt holds a Bachelor of Science degree in mechanical engineering from the University of New Hampshire.

Jens Herzog, Chief Operating Officer at CollectiveSun®, LLC, is a former leading sales executive at SunTechnics Energy Systems Inc. (Conergy AG) who has sold many MWs of PV systems in California. He built the Sales Department for Conergy in the U.S. and sold the first residential and commercial solar systems for them. Among his clients were national grocery chain, a non-profit food bank, and other commercial entities in the U.S. Jens was instrumental in establishing the German American Chamber of Commerce in San Francisco and consulted and advised leading German solar companies on the renewable energy markets in the U.S. He is a German lawyer.

Lee Barken, CPA, LEED-AP is the Chief Community Officer at CollectiveSun®, LLC. He has broad industry experience in renewable energy project finance, environmental commodities consulting and public policy analysis. He is dedicated to helping nonprofits and social ventures develop economically viable energy projects. Lee writes and speaks on the topics of renewable energy project finance, social entrepreneurship, and community financing. Lee plays an active role on the board of directors of Cleantech San Diego and the Impact Investment committee at San Diego Grantmakers. Lee received a Bachelor of Science degree in accounting from San Diego State University where he graduated with honors and academic distinction.

Nicole Withrow is Account Manager for CollectiveSun®, LLC, and she brings with her over 25 years in the tertiary sector from Los Angeles, California to the rural Midwest. She is an experienced sales manager, contract administrator, and fulfillment coordinator. Nicole is dedicated to developing strong relationships with contractors and nonprofits in her role as Account Manager at CollectiveSun by empowering them with resources and providing the support they require as they navigate their journey to solar. She believes passionately that: “We do not inherit the Earth from our ancestors – we borrow it from our children.” A proud mother of two, Nicole resides on an organic farm in the rural Midwest in the heart of Amish country.

Sara Carbone is the Content Marketing Manager at CollectiveSun®, LLC. She has worked in the alternative energy industry as a marketer, copywriter, blogger, and software developer for the past five years. Sara has written for companies such as Aurora Solar, A&R Solar, naak, inc. and her work has been published by Solar Power World. She researches and writes about issues and trends relevant to professionals in the renewable energy field and has worked with companies to develop marketing materials that increase web traffic, educate, and generate brand awareness. Sara helps spread awareness about solar and CollectiveSun’s unique benefits for nonprofit organizations. She has a Bachelor of Arts from Princeton University.

Craig Hunt, Board Chair at CollectiveSun®, LLC, brings over 40 years of experience in oil & gas, wind and solar projects. As a co-founder of Solar Power Partners Inc. and advisor on the founding of SunLink Corp., he has pioneered the development and utilization of PPAs as a primary financing instrument for the solar PV industry, having negotiated many dozen PPAs, including a master PPA with Safeway, a leading national grocery chain. Craig also utilized the sale and leaseback structure for one of the first solar PV project funds in the US. He worked as Senior CPA Manager at Arthur Anderson overseeing numerous leasing transactions, each requiring IRS letter rulings, and as Adjunct Professor of Tax at Golden Gate University. He was also a Navy Jag officer attached to the naval base at Treasure Island and retired there as a Commander.