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Castillo Engineering & RPG Energy Reduce Manufacturer’s Costs by $140,000 with 1.3 MW Solar Project

Companies partner to meet rigorous deadlines to complete the last net metered project in the state

RPG Energy Group and Castillo Engineering were able to meet strict deadlines to have this 1.3 MW solar project grandfathered in to retail net metering, which resulted in 53 percent net energy offset for this manufacturing plant.

Maitland, FL, June 27, 2023 Castillo Engineering and RPG Energy Group, a leading energy efficiency and renewable energy integrator, announced today that they have completed a 1.3 MW behind-the-meter solar project in Indiana, the last net metered project in the state. Located in Greenwood, the project utilizes bifacial solar panels and ballasted racking, and will provide operational savings of $140,000 for an automation machinery manufacturing company in the first year alone.

“After successfully partnering with Castillo Engineering on a solar project for the world’s largest tool company, we knew we could trust their extensive expertise to help us meet the tight timeline for delivery of both the electrical engineering for interconnection and structural feasibility analysis required for this project,” said Colton Cooper, Vice President of Design and Engineering at RPG Energy Group. “Together we were able to ensure that this project was completed on time - all while providing significant savings to our customer.”

Finding ways to provide solar energy customers with savings through site optimization are more important than ever in Indiana, which recently phased out net metering. Since 2004, the Indiana Utility Regulatory Commission had required the state’s five investor-owned utility companies to offer net metering to all electric customers. The policy allowed those customers to sell their excess energy back to utilities at the same rate utilities charged customers for electricity. However, a bill approved by legislators in 2017 started to phase out net metering, with the official end date recently having taken place. As a result, what customers could have earned for selling solar power back to the grid dropped by around 70%.

RPG Energy Group and Castillo Engineering were able to work efficiently together to successfully meet the necessary deadlines - both regulatory and operational, to enable this 1.3 MW solar project to be grandfathered in for retail net metering. In order to meet the net metering deadlines, the companies had to submit the interconnection application and receive approvals within 6 months of project completion.

“We are grateful to have had this additional opportunity to work alongside RPG to deliver substantial long-term savings to this business,” said Christopher Castillo, CEO at Castillo Engineering. “RPG’s expertise in industrial scale, behind-the-meter solar projects was crucial in the success of this project, which had two separate electrical services and meters that had to be assessed to maximize energy offset and utility bill savings.”

In addition to meeting the strict deadlines to enable this manufacturing company to have its solar system grandfathered in to receive retail net metering, the project also resulted in 53 percent net energy offset of the plant. The manufacturer customer, which produces flow meters for liquid, gas and steam systems, can now offset the production of 19,000 flow meters per year as a result of this solar energy system.

About Castillo Engineering

Founded in 1998, Castillo Engineering is a leading design and engineering firm that delivers expertise in full service solar and energy storage design, engineering, and consulting services to developers, EPC contractors and utility companies. Castillo Engineering’s services cover electrical, structural, medium and high voltage for residential and utility-scale projects ranging from 5 kW to 500 MW. The firm’s experience completing 1.5 GW of solar and energy storage projects and unmatched expertise has made it the go-to solar engineering firm for utility-scale ground mount system construction documents for the industry’s top EPCs and developers. The firm was ranked by Inc 5000 two years in a row as one of the fastest growing companies in the U.S., as well as the 9th fastest growing engineering firm in the nation. Castillo Engineering is based in Maitland, Florida, and is licensed in all 50 U.S. states and Puerto Rico. Learn more at

Castillo Engineering Media Contact:

Lisa DeMarco



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