National Grid Pilots World’s First Hydrogen Linear Generator

Maintaining a reliable, resilient grid requires a diverse mix of energy sources. National Grid Ventures (NGV) is expanding that diversity in New York by installing the world’s first commercially deployed, 100% hydrogen-fueled linear generator at its Northport Power Plant in New York.

Learn more about NGV’s linear generator. Video use courtesy of National Grid

The Northport unit will operate on green hydrogen during a 12-month testing period and is expected to be fully operational by September 2026. The Mainspring Linear Generator is fully dispatchable and scalable, with capacity ranging from 250 kW to more than 100 MW. It is uniquely fuel-flexible and can operate on a wide range of gaseous fuels, including hydrogen, biogas, natural gas, propane, and others.

The linear generator will be installed at the Northport power plant. Image used courtesy of National Grid

Aiming for Low Emissions

The Northport facility, the largest power generation site on Long Island, is a natural gas and oil-fired steam electric power plant with 1,564 MW of capacity. In 2005, it became the focus of environmental controversy when local coalitions identified it as the most polluting plant on Long Island and the second largest polluter in the Northeast. The plant has remained exempt from Clean Air Act emissions standards because construction began in the 1960s, before the Act was passed in 1970.

Given its history and central role in Long Island’s power supply, the Northport facility is a strong candidate for piloting the transition to green hydrogen. The project will deliver an emissions-free energy source to help meet New York’s clean energy mandates. The New York Independent System Operator estimates that at least 20 GW of Dispatchable Emission-Free Resources (DEFR) will be required by 2040 to achieve these mandates.

The Linear Generator

Mainspring will provide the linear generator, which will significantly reduce carbon emissions. The generator employs a flameless chemical reaction that keeps peak temperatures below 1500°C, the level at which NOx forms. Hydrogen produces no carbon dioxide emissions when burned. Green hydrogen is created with emissions-free renewable energy.

The generator directly converts linear motion into electricity, which eliminates mechanical losses.

The linear generator core. Image used courtesy of Mainspring

The generators are modular and scalable. Each 20-foot by 9-foot unit contains two generator cores, which operate together to produce up to 18 MW of energy. Inverters and grid tie-ins are included. Multiple units can be used together.

Mainspring began commercial shipments of linear generators in 2020 and now has hundreds of megawatts in field operation.

National Grid’s Pilot Project

The project will demonstrate the linear generator’s viability as a DEFR for Long Island’s electrical grid. The energy can be quickly deployed to supplement other generation sources during peak demand.

Once the operation begins in 2026, the system will be evaluated independently at the Advanced Energy Research and Technology Center at Stony Brook University. The evaluation will assess the generator’s performance, emissions, efficiency, and noise levels to ensure it meets the needs of today’s grid and future demands.

If successful, the hydrogen-fueled linear generator can be introduced to other regions seeking reliable, low-cost, next-generation energy portfolios to support a clean energy transition.

The project is supported by the New York State Energy Research and Development Authority (NYSERDA), the Long Island Power Authority (LIPA), Stony Brook University, and Mainspring Energy.