ForeFront Power completes first steel-free Erthos Earth Mount Solar system at Fresno water treatment plant, cutting electricity costs for the city

ForeFront Power brought its first Erthos Earth Mount Solar system online at the City of Fresno’s Northeast Surface Water Treatment Plant, hitting commercial operation in late March 2026. The project—built in partnership with Erthos for Fresno’s Department of Public Utilities—skips structural steel racking entirely and lays solar modules flat on the ground. That one design choice is what made lower electricity rates possible for the city.

ForeFront Power brings the first Erthos ground-mount system online in Fresno

The Northeast Surface Water Treatment Plant reached commercial operation in late March 2026, making it the first active project where ForeFront Power has deployed Erthos technology. The system now sends solar electricity directly to the city under a 20-year power purchase agreement. ForeFront Power owns the installation and charges Fresno a fixed rate below what the local utility would otherwise bill.

This site is one piece of a bigger picture. ForeFront Power developed a 27 MW-DC solar and battery storage portfolio across three City of Fresno Department of Public Utilities locations, and the Northeast Surface Water Treatment Plant is the first of those three to go live with Erthos Earth Mount Solar.

The Northeast Surface Water Treatment Plant is just the first of three sites ForeFront Power built for Fresno’s Department of Public Utilities.

Rising construction costs in 2023 drove the switch to Erthos technology

The decision to use Erthos didn’t come from a technology preference—it came from a cost problem. In 2023, inflation and supply chain disruptions pushed up the price of labor and materials significantly, and ForeFront Power’s team quickly saw that building a conventional ground-mounted system at the Fresno site would cost far more than originally planned.

PPA economics are tightly tied to construction costs. When a build gets more expensive, the electricity rate charged to the city climbs with it—and a higher rate could’ve made the project financially unviable or simply too costly for Fresno to justify.

ForeFront Power turned to Erthos as a way out. According to senior project manager Erinne Davis, the Fresno site turned out to be well-suited for the approach. The technology helped the company avoid costly civil upgrades and cut expenses tied to steel racking and the labor required to install it.

Eliminating structural steel lowers cost and increases energy density per acre

The core idea behind Erthos Earth Mount Solar is straightforward: lay the modules flat on the ground and skip the steel entirely. No procurement delays, no racking installation, no associated labor costs. That reduction in complexity is what drives the cost per watt down.

Savings on materials are only part of the story. Because modules sit directly on the earth with no row spacing between them, Erthos claims the highest energy density of any solar architecture in the industry—more generating capacity in the same footprint compared to a traditional ground-mount setup.

Flat-on-ground doesn’t mean the system demands perfectly level terrain. Erthos modules can follow site contours up to a 15% slope, which made them adaptable to the natural topography at the Fresno location. That flexibility helped the project move forward without expensive grading work.

The system outperforms projections and is maintained by autonomous cleaning robots

Early performance data from Fresno looks promising. Since entering commercial operation in late March 2026, the system has averaged 101% of expected energy production and has already delivered 862 MWh of electricity to the city—slightly ahead of what the models projected.

Sustaining that output requires regular maintenance, especially cleaning. Dust and debris accumulate faster on flat-mounted panels than on tilted systems, which can cut output more quickly. Erthos handles this with the ErthBot—an autonomous dry nylon brush robot that cleans the array nightly as needed, covers more than 3.5 MW DC of array per unit, and returns to its charging dock automatically after each run.

ForeFront Power and Erthos formalized this through an Energy Services Agreement, under which Erthos takes responsibility for operations and maintenance, including ErthBot deployment. Ongoing management stays straightforward for ForeFront Power while consistent cleaning and monitoring are handled on the Erthos side.

Fresno’s broader solar portfolio is expected to save $122 million in ratepayer costs by 2045

The Northeast Surface Water Treatment Plant is just the first of three sites ForeFront Power built for Fresno’s Department of Public Utilities. The full portfolio includes the Northeast and Southeast Surface Water Treatment Facilities and the Fresno-Clovis Regional Wastewater Reclamation Facility—27 MW-DC of solar capacity in total, each location paired with smart battery storage.

According to ForeFront Power, the combined portfolio is projected to save Fresno ratepayers more than $122 million through 2045. That figure reflects two decades of electricity purchased at fixed, below-utility rates rather than whatever the local grid charges over time.

Here’s the quick version: ForeFront Power completed its first Erthos Earth Mount Solar installation at Fresno’s Northeast Surface Water Treatment Plant in late March 2026. The steel-free design cut construction costs enough to keep the project viable under a 20-year PPA. The system is already running above its energy production targets, is cleaned nightly by autonomous robots, and it anchors a three-site, 27 MW-DC portfolio that Fresno expects will save ratepayers over $122 million by 2045.

Kelly Lippke

Kelly is an experienced writer with 15 years of experience exploring the big stories that shape our world, from tech breakthroughs and space exploration to climate, energy, and the fascinating quirks of science. She has a talent for turning complex ideas into sharp, memorable insights that stay with readers long after they’ve finished reading.