Our Team

A1 Sun Inc. is an innovative and creative solar design and installation firm. Since incorporation in 2007, we have successfully designed and installed superb solar photovoltaic and thermal systems. Each member of the A1 Sun Team strives for excellence. A1 Sun has an exemplary safety and quality record with 100% customer satisfaction.

The A1 Sun Team

Larry Giustino


In 1965 at the age of 11, Larry manufactured a photovoltaic cell through a Bell Telephone Lab school program in San Diego, CA. Starting with a raw silicon ingot and after weeks of preparation phases, the polished and doped pie shaped quarter silicon wafer produced about 0.5 DC volts in full sunlight. It worked perfectly converting sunlight into electricity and was a brilliant success. As a consequence, Larry was already convinced of the efficacy of solar electricity four plus decades ago as a elementary school student. After graduating from UC Berkeley, he attended Dr. Marshall Merriam’s UC Solar Engineering graduate seminars. He went to work at Solar Station, Inc., designing and installing solar thermal systems in the 70’s and 80’s. He supervised all phases of the design and installation of the UC Berkeley Student Co-op solar thermal systems, still working today. US Federal Solar Tax Credits were reinstated in 2005. On Kathleen’s insistence, Larry installed solar photovoltaic modules on their home and office. It felt so good, Larry re-entered the solar field selling, designing, and installing solar. With long time associate Paul Cooper, Kathleen and Larry founded A1 Sun, Inc. in 2007 to meet the growing solar demand of residential and commercial clients.

Kathleen Giustino


Kathleen earned a BA from UC Berkeley, an MA, and NBCT degrees. From A1 Sun’s inception, Kathleen’s essential work is integral part of this company. She is involved in the planning and execution of day-to-day activities, as well as contributing her own personal vision and renewable energy goals.

Paul Cooper


Paul is a licensed general building and plumbing contractor. He has a lifelong interest in physics and alternative, sustainable, renewable energy. Paul was the co-founder and president of the Alternative Energy Collective from 1978 to 1987. He also founded and worked with Solar Station, Inc. from 1979 until 1989. In 2007 Paul helped found A1 Sun, Inc. and advises, consults, and oversees A1 Sun’s operations and manages the intelligent and talented crews. He is also currently the Vice-President of the Alameda Electric Car Association.