Mainspring Energy, the developer of a new generator technology that use fuels like biogas and hydrogen, has unveiled its Mainspring Linear Generator, with a $150 million contract with NextEra Energy Resources.
The company’s technology represents a significant step in the transition to a zero-carbon power grid, given its ability to shift between traditional natural gas sources and alternative fuel sources like biogas and hydrogen.
So far, the company’s generators are under contract with a national supermarket chain that’s using the company’s tech at 30 of its grocery stores. The company began shipping pilot units in June and will begin commercial shipments in mid-2021 according to a statement.
The company’s tech was initially developed at a thermodynamics lab in Stanford University where co-founders Shannon Miller, Matt Svrcek and Adam Simpson were working. Its design enables the rollout of generators that can replace traditional diesel and be used to improve the resilience of industrial sites against natural disasters.
Their linear generator, which the company said differs from engines, microturbines, and fuel cells, is a device that converts motion along a straight line into electricity using heat or chemical energy. In Mainspring’s case, a low-temperature reaction of air and fuel drives magnets through copper coils to produce electricity.
It’s the combination of the design and control software developed by the company that allows its equipment to produce high-efficiency, dispatchable power, without the nitrogen oxide emissions associated with other generators, the company said.
The technology caught the eye of investors like Bill Gates and Vinod Khosla’s eponymous investment firm Khosla Ventures, along with some oil and gas companies like Equinor and utilities like American Electric Power. To date, Mainspring, which used to go by the name Etagen, has raised well over $80 million in financing.
In its approach to energy generation without the need for more complex mechanical systems or catalysts, Mainspring is akin to other startups like the Robert Downey Jr. and Bill Gates-backed Turntide Technologies that are trying to provide more elegant, software enabled solutions to motors and generator technologies.
Mainspring’s generators achieve their low-capital and maintenance costs through use of standard materials, only two moving parts and an innovative air bearing system that eliminates the need for oil, the company said. It operates without the use of complex mechanical systems or expensive catalysts.
The company also touted its ability to spin up and spin down in response to conditions on the energy grid, which means that it can pair well with solar power or battery storage.
“One of our customers’ key drivers, in addition to carbon savings, is to save cost from their current grid prices,” said Miller, in a statement. “Our products can provide substantial savings to commercial customers on their electricity costs with a typical Energy Services Agreement. In this energy-as-a-service scenario, customers pay nothing up front and realize annual savings starting in the first year.”
Mainspring’s first commercial product is designed for a rated output of 250 kW and packaged in a standard 8′ x 20′ container, according to a statement. Those packages integrate two of the company’s125 kW linear generator cores, working in tandem, and combines UL-listed grid-tie inverters and auxiliaries into a turn-key package, the company said. Future configurations will provide higher power output to serve industrial businesses, data centers, hospitals, smart cities and utility grid-level applications.
“Many commercial and industrial customers as well as utilities want clean, reliable power generation, with the capability to switch to 100% renewable fuels like biogas and hydrogen as they become available,” said NextEra Energy Resources President and CEO John Ketchum, in a statement. “Mainspring is able to integrate clean onsite generation with both renewables and the grid and we’re pleased to support bringing this innovative product to market.”