Voltares Picks Stem PowerTrack for 68-MW Solar Plant in Georgia

• Stem will supply PowerTrack software, redundant plant controls and on-site hardware for Voltares' 68-MW Marneuli-I solar plant in Georgia.
• Stem calls it the country's first utility-scale solar project; Georgia had 317 MW of solar PV at the end of 2025.
• Commissioning is scheduled for the first quarter of 2027, leading directly into commercial operation.

Stem Inc. will supply its PowerTrack software and power plant controls for Marneuli-I, a 68-MW solar plant in Georgia. Developer Voltares is building it about 40 kilometers south of Tbilisi. Stem described the project as the country's first utility-scale solar facility in a statement on Nov. 12.

The package combines software, controls and on-site hardware. PowerTrack handles site-wide monitoring, performance analytics and real-time plant control. The power plant controller has primary and secondary control levels, so operations continue if one control component fails. It will hold output to a 50-MW maximum export limit. It will also exchange real-time telemetry with Georgian State Electrosystem, the transmission system operator, over a 220-kV grid connection.

The European Bank for Reconstruction and Development calls Marneuli Georgia's largest utility-scale solar plant. The bank approved a senior loan of up to $25.5 million (€22.1 million) in December 2025. The borrower is ITEC LLC, fully owned by Voltares Power Projects. Georgia had 317 MW of solar PV at the end of 2025, up from 139 MW a year earlier, IRENA data show.

The plant in numbers

• 68 MW of solar capacity, with exports capped at 50 MW, according to Stem.
• 100 GWh, approximately, of expected annual generation.
• 16.8% implied capacity factor: 100,000 MWh ÷ (68 MW × 8,760 hours) (list.solar calculation).
• $34.9 million total project cost, according to the EBRD.
• $0.48 per watt, roughly, from $34.9 million over the 73-MWp DC rating in Voltares documents (list.solar calculation).
• 21%: the plant's 68 MW as a share of Georgia's 317 MW of solar PV at the end of 2025 (list.solar calculation).

Project documents give different figures. Voltares lists phase one at 73 MWp DC and about 91 GWh a year. Its October 2025 summary gave 50 MWac and 104.01 GWh, with completion expected by mid-2026. Panels stand at least 1 meter high so sheep can graze the 82.6-hectare site.

"Projects like Marneuli-I require a technology partner that understands both plant performance and the complexities of connecting renewable energy to the grid," Matt Tappin, Stem's president of software, said.

Stem's board began a review of strategic alternatives on Oct. 26. On Nov. 3, Energix US brought its 152-MWdc Border Basin plant in Ohio online on PowerTrack.

Commissioning of Marneuli-I is scheduled for the first quarter of 2027, leading directly into commercial operation. Construction of a 115-MWp second phase is set to start in the same quarter, according to Voltares.