The combined company is expected to become the fourth largest residential solar system provider in the US. It will be led by Frank Kneller, CEO of Horizon Solar Power.
The merger will also result in making the combined firm as the second largest provider of residential solar systems in California. It was orchestrated by Solar Spectrum's shareholders led by Northern Pacific Group which is based in Wayzata, Minnesota.
Since 2008, Horizon Solar Power has served as a major designer and installer of residential and commercial solar systems in California.
The transaction was completed on 17 August 2017.
Following the completion of the transaction, Solar Spectrum's shareholder group includes Northern Pacific Group, International, Hercules Capital, DGB Investments, Bindley Capital and the management teams of Horizon Solar and Solar Spectrum.
Horizon Solar Power CEO Frank Kneller said: "This combination blazes a new path for residential solar as we combine Horizon's six consecutive years of profitable growth and Solar Spectrum's best-in-class technology driven customer experience.
"Not only does this merger position Solar Spectrum which will be operated going forward under its Sungevity brand, as the largest residential solar company in Southern California, but also as one of the fastest growing solar companies in the country.
“This strong market position, coupled with our financial strength and scalable business model, will enable us to seize market leadership through further share gains and industry consolidation."
Northern Pacific Group Managing Partner Scott Honour said: "With this agreement, we have combined two successful and well-established solar companies in the United States under one brand. We now have one of the fastest growing and best-capitalized solar companies in the country.
"The management team, led by Frank Kneller, will be capable of both growing the business organically as well as pursuing additional strategic combination opportunities. We are confident about Sungevity's ability to further differentiate itself as the leader in the residential solar industry."