Automotive producer Toyota has developed an idea mannequin that explores how hydrogen fuel generated whereas driving – “boil off fuel” (vaporised hydrogen) – can be utilized, doubtlessly growing the effectivity of liquid hydrogen as an engine gasoline. The corporate is in search of companions to tackle the problem of growing the know-how collectively.
The idea was showcased final weekend on the ultimate spherical of the 2024 ENEOS Tremendous Taikyu race collection in Japan, the place the sector included a GR Corolla working on liquid hydrogen. Toyota will proceed to make use of the difficult world of motorsports to refine its automobiles and the talents and abilities of individuals, along with its companions, to realize carbon neutrality.
The know-how rules
Liquid hydrogen has the next density than gaseous hydrogen, however whereas this implies a higher quantity may be saved in a tank of the identical capability, it presents the problem of “boil-off”. This can be a downside for all liquid hydrogen programs, the place the gasoline saved within the tank evaporates because of pure warmth getting into from the surface. Till now, the boil-off fuel generated within the tank whereas driving has been launched into the environment with out getting used.
The brand new idea mannequin exhibits how the boil-off fuel is likely to be used. Though nonetheless within the idea stage, this know-how might enhance the power effectivity of the complete liquid hydrogen system by recovering and utilizing the boil-off fuel as power.
Reusing boil-off fuel as gasoline
Toyota is engaged on the event of know-how to provide reusable gasoline by sending boil-off fuel launched from liquid hydrogen within the tank to a self-pressuriser – a tool that will increase strain with out counting on exterior power. The boil-off fuel may be transformed again to usable hydrogen gasoline for the engine by making use of strain, however growing the strain sufficiently often requires power, comparable to electrical energy. The self-pressuriser featured within the Toyota idea makes use of the strain of the boil-off fuel to extend strain by two to 4 occasions, adequate to provide reusable gasoline with out utilizing extra power.
Producing electrical energy with boil-off fuel
Throughout the pressurisation course of, a specific amount of surplus boil-off fuel remains to be launched. That is fed right into a small Toyota gasoline cell stack, the place it produces electrical energy by a chemical response. The electrical energy generated can be utilized to energy parts such because the liquid hydrogen pump. If realised, it will likely be doable to make use of boil-off fuel to provide supplementary electrical energy equal to the quantity generated by the alternator, resulting in an enchancment in power effectivity.
Secure launch of surplus boil-off fuel
Boil-off fuel that’s not used within the electrical energy technology course of is transformed into water vapour by a catalyst and safely launched exterior the car.
