ForeFront Power has achieved commercial operation of a new solar installation at the Northeast Surface Water Treatment Plant in Fresno, California, utilizing the Erthos Earth Mount Solar system. The Erthos technology places solar modules directly on the ground, eliminating the need for structural steel racking and its associated procurement and installation costs. Water and wastewater treatment facilities are typically among the largest energy consumers for municipal governments, making them strategic targets for on-site solar generation aimed at reducing operating costs.

ForeFront Power first engaged with Erthos in 2023, when inflation and supply chain disruptions had driven up labor and material costs to the point where the project's payback period had become unattractive for the city of Fresno.

"After conducting our due diligence and vetting Erthos technology, we discovered that the Northeast Surface Water Treatment Plant was an optimal site for an Erthos application," said Erinne Davis, senior project manager at ForeFront Power. "Erthos helped us avoid significant, expensive civil upgrades, as well as the cost of steel for racking and the labor to install that racking. Realizing these savings on the installation is what enabled the project at this site to move forward."

The Erthos installation is part of a broader solar and battery storage portfolio that ForeFront Power developed for Fresno's Department of Public Utilities (DPU) across three facilities: the Northeast Surface Water Treatment Facility, the Southeast Surface Water Treatment Facility, and the Fresno-Clovis Regional Wastewater Reclamation Facility. Together, the DPU projects total 27 MW-DC in capacity and are projected to save ratepayers more than $122 million by 2045.

Since entering commercial operation in late March 2026, the Erthos system has exceeded performance expectations, operating at an average of 101% of projected energy production and delivering 862 MWh of energy to the city. ForeFront Power and Erthos continue collaborating to optimize system performance.

Beyond avoiding structural steel costs, ForeFront Power achieved a higher generating capacity per acre due to the unique Erthos architecture. With no row spacing required, Erthos claims the highest energy density of any solar architecture in the industry. This stands in contrast to conventional fixed-tilt and single-axis tracker systems, which require row spacing to minimize inter-row shading and accommodate maintenance access. Additionally, although the modules are mounted flat on the ground, the system can follow terrain contours of up to a 15% slope, making it adaptable to the natural topography of the Fresno site.

Under an energy services agreement, Erthos will maintain the solar energy system, including regular array cleanings conducted by the proprietary ErthBot — a dry nylon brush autonomous cleaning robot designed specifically for PV array maintenance. Automated cleaning is particularly relevant for ground-mounted systems in California's Central Valley, where dust accumulation can reduce module output over time.