PG&E, NextEra Energy pilot natural gas, biogas generator
Working with a subsidiary of NextEra Energy Resources and Mainspring Energy, PG&E deployed the 240 kW Mainspring linear generator as part of its commitment to integrating cleaner generation solutions for replacement power during emergencies like winter storms or earthquakes, and Public Safety Power Shutoff (PSPS) events.
A linear generator – distinct from an engine, microturbine or fuel cell – is a device that directly converts motion along a straight line into electricity using chemical or thermal energy.
Currently, PG&E strategically deploys mobile diesel generators across its service area during emergencies and PSPS outages to rapidly re-power thousands of customers. These generators are connected to the grid at substations, distribution microgrid sites, community resource centres, and critical facilities as needed and available.
For the Angwin deployment, the linear generator is connected to both PG&E’s electric distribution system and its natural gas distribution system. NextEra Energy Resources is purchasing biogas fuel that is renewably produced at another location. The procured biogas is processed and injected into the existing gas distribution infrastructure, offsetting the linear generator’s usage of natural gas.
The goal of the pilot involving biogas is to demonstrate the performance of new, cleaner electricity generation technology at a PG&E distribution microgrid. The linear generator will be paired with the onsite diesel generator to ensure a reliable service for the community of Angwin, and the company will study whether the hybrid solution can cut diesel use and emissions during emergencies or PSPS events this year.
“We know how important clean, reliable energy is to our customers and communities,” said Jason Glickman, executive vice-president of engineering, planning, and strategy at PG&E.
“We are excited to explore new technologies like the linear generator to help keep customers powered during larger outages while also reducing the use of diesel backup generation. This is a low-emissions, resilient, and affordable alternative that holds a lot of promise for our future.”