Dolphin N2

Dolphin N2

High efficiency, near-zero emissions heavy-duty power

Dolphin N2 Ltd. was launched last year as an independent company from Ricardo to further commercialise and technically develop the intellectual property coming from over a decade of research on near-zero emissions technology.


The research and investment have led to two game-changing technologies that completely redefine the combustion engine and offer unprecedentedly high efficiency paired with near-zero emissions in the case of the flagship technology, CryoPower.

The technologies developed at Dolphin N2 are aimed at providing significant benefits to the heavyduty engines used in transportation, decentralised power generation, off-highway and agricultural applications, as well as marine propulsion.

Customer Benefit

The highly efficient and clean use of fossil and reduced carbon fuels in a low carbon economy is attractive to several end users and strategic partners in commercial sectors:

  • Truck and gen-set manufacturers looking to provide solutions to customers that meet greenhouse emissions (CO2) targets and/or clean-air emissions (NOx) limits in cities, with substantial operating cost reduction and range and refuelling time maintained
  • Operators of distributed power generation plants providing fast response, additional capacity, grid resilience and grid services to an increasingly low-carbon power generation market
  • Distributed renewable solar & wind energy assets can store surplus energy through N2 generation services and co-locate with CryoPower users ready for deployment at peak times
  • Oil and gas majors will be able to extend the application of fossil fuel with net decarbonisation, by using it more effectively in conjunction with cryogenic N2 produced by renewable electricity
  • Higher cost bio and synthetic fuels become more economical and less-reliant on subsidies when used in a more efficient CryoPower engine
  • Marine engine OEMs and shipbuilders, enabling achievement of a global commitment to 50% greenhouse gas reductions by 2050


The early development work carried out on the single cylinder test rig installed at the University of Brighton has validated the potential of CryoPower to target a 60% brake thermal efficiency (equivalent to a fuel economy improvement of in the region of 30% in comparison with the best current heavy-duty engines, and matching the peak efficiency of combined cycle power plants) and has also demonstrated the highly impressive low-NOx emissions credentials of the CryoPower Cool Combustion process.

The CryoPower rig tests of the engine
Pictured above: The CyroPower rig tests the combustion system

In addition to demonstrating the potential of CryoPower, the research team has also developed a simplified engine concept known as ThermoPower. This concept uses the same basic engine architecture as CryoPower but without the use of liquid nitrogen. ThermoPower is particularly suited to spacesensitive vehicle applications and represents a lower cost and more readily adoptable solution achieving over 50% thermal efficiency (equivalent to a fuel economy improvement of 15% in comparison with the best current heavy-duty engines) while retaining the low emissions potential of CryoPower.