Industrial Power Systems Inc (IPS) has introduced a variable speed generator (VSG) controller, which it says is a cost-effective tool to curtail port equipment's harmful air emissions.

It can be applied to cargo handling equipment powered by engine generator sets, like ship-to-shore cranes, rubber-tyred-gantry cranes and the new diesel electric straddle carriers.

"The ultimate goal is to completely eliminate the discharge of harmful substances into the atmosphere, but that will take years," IPS president Bill Young said.

He said the VSG controller was designed to reduce harmful air emissions by up to 40 per cent, cut fuel use by 40 per cent and cut engine noise by as much as 50 per cent.

IPS said the concepts guiding development of the VSG controller had been around for 25 years.

"The US military has used [the product's concept] for quiet generators on submarines, ship and shore power feeders and the scientific community has used it for power source flexibility," said Mike Massingill, an IPS spokesperson.

"Many of these earlier devices were unreliable, required special alternators or permanent magnetics, and were not as flexible or software modifiable as ours," he said.

IPS developed the product design with Youtility Inc and began marketing it in mid-June after receiving a full patent. Located in Jacksonville, Florida, IPS develops and installs medium-to-low voltage electrical systems and marine industrial switch gear for electrical utilities, cement plants, petrochemical plants, and generator controls for cruise liners, tankers, US naval vessels, and container vessels.