Meet the Team at Solar Gain, Inc.


Ken Riley


Ken Riley is a registered Civil Engineer and has worked in the construction industry for over 30 years with the Kiewit Companies. He has held executive oversight for multiple business units, and estimated, negotiated, and executed numerous large projects ranging from $250 million to $1+ billion construction value. The include roads, bridges, dams, rail projects, and treatment and power plants. Notable projects include the Carlsbad Desalination Plant, the Pine Tree Wind Farm commissioned by the LA Department of Water and Power in the Tehachapi Mountains, the Los Angeles Freeway 405 infrastructure repair project, a high-stakes project also known as Carmegeddon, and the Benicia-Martinez Bridge in Solano County, California.  In 2016 he became involved in the solar industry and, through a mutual friend, met Roman Black. Solar Gain had entered the California market and Ken and Roman saw an opportunity to form a partnership and help Solar Gain take on the challenges that come with growth. Ken is a past chair and active board member of the Tahoe Prosperity Center and, when he’s not in Tucson, spends his time backpacking, skiing, and enjoying his home and family in Lake Tahoe.

Roman Black

Vice President - Sales & Marketing

Roman holds significant experience in commercial solar project development and sales, and is committed to serving our clients in the expanding California and Arizona markets with continued excellence in his role as VP of Sales & Marketing. Roman earned his degree in Finance from the University of Arizona, and spent several years in Costa Rica expanding his knowledge and skill set in sustainable industries. While in Costa Rica, he served as project manager for the construction of custom homes that integrated LED lighting, rainwater harvesting, black water recycling, and solar and wind power. After returning to the United States, Roman took on responsibility for leading Solar Gain and helmed the company for eight years as President during periods of tremendous growth.

At Solar Gain he builds the best possible financing options through strong funder relationships and aggressive pursuit of financial benefits and incentives for our clients. Roman is a founding board member of the Southern Arizona Green Chamber of Commerce.


Ron Leuzinger

Chief Financial Officer

Ron came to Solar Gain in early 2017 with nearly 30 years of leadership experience in various finance and operations management roles.  Upon graduating from the University of Wisconsin with degrees in Accounting & Finance, he began his career in public accounting with Ernst & Young where he earned his CPA certification.  Ron has led process improvement initiatives in multiple manufacturing, engineering design, and project management enterprises in the water treatment and aerospace sectors.  Most recently, Ron spent 16 years in the medical device industry as part of Smiths Medical and Teleflex, focused on supply chain strategy and product cost optimization.

While Ron now makes his home in Tucson and enjoys motorcycling, biking, and hiking in his spare time, he remains faithful to all things Wisconsin – including Packers, Badgers, and cheese.

Tim Graunke

Project Development

Tim was born and raised in Tucson, AZ and is the oldest of 5 siblings. He went to Salpointe High School, and graduated from the University of Arizona in 2007 with a Bachelor of Economics. In early 2008, Tim moved to Honolulu and started a career in solar. Early experience as a project and construction manager led to a strong understanding what it takes to complete projects on schedule and within budget. He soon became Lead Commercial Project Manager for one of Hawaii's top companies in 2011. Later, he returned to Tucson and started working with Solar Gain in late 2015 developing projects pre- & post-contract execution.

Jeremiah Mosij

Marketing & Sales Director

Jeremiah has been working in the sustainability sector for over seven years. His father is a general contractor, so construction has been a way of life at a very young age. Before finding his home at Solar Gain, Jeremiah was certified as a Rainwater harvesting practitioner under the instruction of Brad Lancaster and Lincoln Perino. When Jeremiah is not out saving the world, you can find him playing in a local Spaghetti Western band called Hey, Bucko! in downtown Tucson.


Brian Smith

Commercial Superintendent

Brian is a NABCEP-certified PV installation professional with more than six years of experience in both residential and commercial PV projects throughout southern Arizona. With a bachelor’s degree in Mechanical Engineering and additional photovoltaic training, he uses his advanced education to oversee the multiple facets of complex photovoltaic installation projects. Brian is also involved in Solar Guild, a local nonprofit that develops solar projects that benefit the community. Through Solar Guild he has led numerous projects, including for Biosphere 2 and Catalina State Park.

Brett Lange

Electrical Superintendent

Brett is an electrical superintendent/ lighting specialist. He is a native Tucson resident, proud family man, Scouter, and father of 2. He has 30 years of electrical experience in the alternative energy& electrical fields including years of experience in the lighting design field

Sol Hassler

Lead Commercial Designer

Sol has 8 years of solar installation and design experience. He holds an Associate’s degree and is NABCEP Solar Electrical Installation-certified. Sol has made Tucson his home for the last ten years and has a deep fascination with sustainable design. He always has several active projects outside of work, the subject matter of which varying greatly.

Will Lawton

Warehouse Manager

Born and raised in Tucson, Arizona, Will understands the importance of conserving natural resources. Will majored in Natural Resources Conservation and Management at the University of Arizona after it became clear that his work would focus on conservation. Upon graduating, he came across the opportunity to work for a solar company, which was a great way to get into conserving precious natural resources, while also being a part of an expanding effort to develop and produce renewable energy.



Santino “Sonny” Perez

Lead Technician

Sonny was born and raised in Tucson, Arizona, and has been installing P.V. Solar for 4 ½ years. Since he joined Solar Gain in 2014, he has taken on added responsibility and supervisory roles, rising to the Lead Technician role. And he loves his job! Says Sonny: “I love working for this company, and couldn’t ask for better co-workers, and the bosses are great. It’s huge to be with this company as we continue to grow. Thank You, Solar Gain!”