The Opcon Powerbox is an Organic Rankine Cycle (ORC) implementation. Waste heat is used by a heat exchanger to vaporize a working fluid with a boiling point lower than water (thereby enabling the exploitation of low grade waste heat). The gas expands over an expander, which drives a generator to produce electricity. The fluid is then cooled, and a pump increases its pressure to 30 bar, and circulates it back through the first heat exchanger.

The Opcon Powerbox directly influences the performance of ships by reducing the amount of fossil fuels they consume during operation by 5-10%, cutting carbon, NO_x and sulphur emissions. There are currently around 16,000 registered marine vessels in the world with power outputs above 10 MW, while the global, commercial-shipping fleet is considered to account for between 4 - 5% of global carbon emissions.

The first reference installation, a marine installation that utilizes waste heat for electricity production, is currently underway. Here, the Opcon Powerbox is being integrated with a two-stroke MAN B&W 8S60ME-C8 engine aboard a newbuilding owned by Wallenius, the Swedish shipping group.

The Opcon Powerbox can be applied in both newbuildings and retrofits. It caters to low-temperature applications and can be integrated with smaller engines in contrast with existing WHR units that are targeted at higher-temperature applications and larger engines.