Category Logo

Knoxville business leader launches solar and renewable energy company Chroma Energy Group

April 17, 2023


As Chief Operating Officer at Stowers Machinery Corporation, East Tennessee’s Caterpillar equipment distributor for 60 years, Ed Rottmann may not seem a likely candidate to lead a renewable energy company. In his current role, he works with heavy equipment, construction machinery, engines and electric generators. But after 10 years growing the family business, Rottmann brings a unique perspective and entrepreneurial acumen to his launch of Chroma Energy Group.

“In some ways, I’m going into renewables because I love fossil fuels,” Rottmann said. “I’m bringing a pragmatic approach to this venture. I see the distinct need for both renewables and fossil fuels to complement each other, rather than compete, and that puts the Chroma Energy Group at an advantage. Sustainability is an important consideration, but our business decisions won’t be dictated by that singular mission. The United States needs a reliable base load of electricity, but the United States also needs carbon-free electricity. Accomplishing both of those at the same time requires a viable solution to augment and diversify our energy sources. We have opportunities to create and support resiliency, utilize all our natural resources, and increase our grid capacity today and tomorrow for our children.”

Ed Rottmann

The launch of Chroma Energy Group is precipitated by the acquisition of Knoxville-based Efficient Energy of Tennessee, a well-respected full-service solar engineering, procurement and construction contractor.

Over the past 14 years under the leadership of president and owner Robbie Thomas, EETN has established its team as trusted solar photovoltaic (PV) experts, known for high standards of workmanship, cost-effective construction and use of known, quality industry products.

“I have been very fortunate to have the opportunity to work with Robbie and have Efficient Energy of Tennessee become a launchpad for Chroma Energy Group,” Rottmann said. “I’m thrilled to welcome his 14 employees on board at our new company and build on the legacy of his company.”

EETN has provided general contracting services for utilities, government, industrial and commercial businesses across the Southeast and Midwest.

“I am proud of what we’ve built, our team and the impact we’ve had for our customers, this industry and the future of sustainability,” Thomas said. “The past 14 years have been one of the most challenging yet most rewarding experiences I could have imagined. I count myself fortunate to have been allowed the opportunity to work with some of the most special and talented people this industry has to offer. I certainly look forward to seeing Ed take the reins and lead our outstanding team as he is getting an excellent, quality-driven and hard-working group. Efficient Energy of Tennessee will serve as a strong foundation for Chroma Energy Group and the great work they will do.”

Chroma Energy Group will hit the ground running by completing EETN projects in process and honoring upcoming commitments. Rottmann plans to focus on solar installation but hasn’t ruled out future growth into other renewable energy sources and products, including but not limited to storage and other clean technology initiatives.

Rottmann will remain connected with the family business, working on projects alongside his wife, Lisa Stowers Rottmann, President of Stowers Machinery Corporation. He hopes Chroma Energy Group will build a similar legacy as Stowers, a third-generation family-owned company.

“I love an internal combustion engine,” Rottmann said. “I’m not renouncing fossil fuel, and I’m not leaving Stowers Cat. But I see the trajectory of the energy sector, and I’m excited. We’re going to be adding new power sources, building on proven technology and creating the infrastructure that will serve future generations. I’m confident in what we are building and eager to explore its nearly infinite potential.”

Prior to joining Stowers Machinery Corporation, Rottmann worked as a financial analyst for Missile Defense Agency and an account manager for NCR Corporation. He has a bachelor’s degree in business administration from University of Kentucky and a MBA from Vanderbilt University. Rottmann serves as president of the board for The Tennessee Theatre and as board member for the Tennessee Road Builders Association. He resides in Knoxville with Lisa and their daughter, Natalie, and sons Gabe and Owen.

For more information and to contact the company, visit