High Efficiency Solid Oxide Fuel Cell and Internal Combustion Engine Hybrid Power System

Improved Energy Generation

At a Glance

A new method for power generation combines a solid oxide fuel cell (SOFC) stack integrated with a high efficiency stationary engine The new power system combines systems for greater energy efficiencies and beneficial cost savings.


Solid oxide fuel cells (SOFCs) are a scalable and efficient form of energy production, which minimize greenhouse gas emissions. SOFCs use a solid oxide electrolyte to oxidize gases by electrochemically conducting oxygen ions from a cathode to an anode. Generally, hydrogen, carbon monoxide, or a hydrocarbon molecule are oxidized on the anode side.

SOFCs do not require expensive catalyst materials. However, one drawback of SOFCs is that they require high temperatures to operate efficiently, sometimes at temperatures of 750° C. to 1000° C. High capital cost and poor durability have been significant barriers for solid oxide fuel cell technology to achieve widespread adoption in commercial distributed power generation applications. In part, these challenges have historically been associated with their high operating temperatures (750-1000° C.). While progress in cost reduction and durability has been made, even at high production volumes, relatively high balance-of-plant costs (-760 $/kW), and low lifetime average system efficiency (45-55%) still limit their value proposition and market potential. Additionally, high temperature SOFC technology has long suffered from low robustness/durability, poor dynamic response, and high stack and balance-of-plant (BOP) costs.


This hybrid power generator combines a solid oxide fuel cell (SOFC) with an internal combustion (IC) engine to produce energy at a 71% efficiency, an increase of about 20% when compared to other natural gas power production. The SOFC and IC are linked in the process such that power may be generated using the byproducts of one system to power the other. The thermal management of the system is conducted through internal fuel feedstock reform, and the system is able to achieve a lower balance of plant cost compared to current market options.


  • Power is produced by natural gas at a higher efficiency, 71% efficiency compared to 45-55% efficiency is available in market competition
  • 100-kW scale of electricity produced
  • Reduced fuel consumption
  • Greater efficiency of overall power generation leads to decreased cost
  • 900 $/kW balance of plant cost, compared to -760 $/kW available in market competition
  • Lower supporting machinery cost
  • Lower operating temperature improves lifetime of the fuel cell


  • Grid electricity generation
  • Smaller units for localized energy generation
Last Updated: April 2022
Hybrid power generator system diagram

Available for Licensing
TRL: 3

IP Status

Robert Braun
Todd Bandhauer
Bret Windom
Dan Olsen

Reference Number
Licensing Manager

Steve Foster