Gas turbines for a faster journey
Gas turbines are the beating heart of the ships in the Horizon series. Combining this technology with steam turbines allows improvements on today’s speed and service, while at the same time cutting emissions and ensuring competitive energy consumption. Gas turbines have long been used in the industry, but only now will they be powered by hydrogen. This provides a unique opportunity to accelerate shipping’s climate transition.
One major advantage, in addition to speed, is that the gas turbines will have a multi-fuel design, allowing them to be adapted to different types of fossil-free fuel. This means that as well as hydrogen, fuels such as methanol, e-methanol and biogas (LBG) can also be used. With a relatively simple adjustment to the turbines, it is possible to switch fuel from hydrogen to another gas or liquid fuel. There is also the option of blending hydrogen with biogas, for example.
A turbine converts energy from a liquid or gas into mechanical work. A typical gas turbine unit with generator is 14 metres long, weighs around 85 tonnes and has a power output of up to 15 MW. The technology is, in many ways, similar to an aircraft engine – air is sucked in one end and pressurised in the compressor. The compressed air is then channelled into the combustion chamber, where hydrogen enters and is ignited. The combustion of the gas drives the turbine. The turbine drives a mechanical shaft that is connected to a generator or directly to the propeller shaft via a gearbox.
The gas turbine is also combined with a steam turbine, which is placed by a smaller funnel at the top of the ship. The steam turbine recovers residual energy from the steam i.e. water vapour generated during combustion and produces electricity for the ship.
The ships have a multi-fuel design with an emphasis on hydrogen. They can thus be adapted to the fossil-free fuels that are available, depending on supply and technical developments. As such, the Horizon series is well equipped for an effective transition to zero emissions.