Benefits of Dynamic Skip Fire for Improved Natural Gas Engine Performance

Dynamic Skip-fire technology improves fuel econony of compressed natural gas engine.

The Regents of the University of California on behalf of the Berkeley campus


Berkeley, CA

Recipient Location


Senate District


Assembly District



Amount Spent



Project Status

Project Result

The project collected data on the potential fuel savings and emissions reduction of trucks and large displacement engines when combining compressed natural gas (CNG) engine with Dynamic Skip-Fire (DSF) technology, an innovative approach to cylinder management for large spark ignited engines.[?[o:p] The research effort was completed and it has been proven that DSF improves the engine’s fuel economy and does it by not only reducing pumping losses as was predicted, but also reducing heat losses.

The Issue

Existing spark-ignited natural gas engines can be greatly improved in their performance by removing losses incurred under part load and by increasing power density. Achieving part loads via a throttle valve causes significant loss in fuel economy and thus presents a technical barrier to overcome.

Project Innovation

The goal of this project was to improve fuel economy on natural gas engines using advanced skip-firing technologies in combination with cylinder deactivation under naturally aspirated and boosted intake. Skip fire technologies have evolved over years proving to be quite effective. The basic concept of skip fire operation is to use firings or non-firings of engine cylinders to satisfy engine torque demand rather than throttling or other torque reduction mechanisms which degrade overall thermal efficiency of the engine. Due to the small market of natural gas engines, the potential benefits of these new skip fire technologies have not been fully explored in the past. Through research and development, this project aimed to validate the benefits of a skip fire approach in natural gas spark-ignited engines.

Project Benefits

In California, natural gas usage for transportation in 2012 was 17 billion cubic feet per year. If dynamic skip-fire technology is successfully commercialized for the heavy-duty vehicle market, and with a reasonable penetration of 10 percent, the potential in natural gas savings is 340 million cubic feet per year.

Environmental & Public Health

Environmental Sustainability

Dynamic skip-fire technology has the potential to save 340 million cubic feet of natural gas per year. This will reduce greenhouse gas emissions significantly.

Energy Security

Energy Security

Commercializing advanced natural gas engines will reduce the petroleum demand in California. The dynamic skip-fire technology integrated in natural gas engines further improves fuel economy by 20 percent.

Key Project Members

Project Member

Robert Dibble

Contact the Team