The LiquidPiston engine is based on a patent-pending thermodynamic cycle, called the "High-Efficiency Hybrid Cycle" (HEHC), which borrows elements from Otto, Diesel, Atkinson, and Rankine cycles. Several critical design features make the LiquidPiston engine architecture both versatile and capable of outperforming conventional engines on all parameters.
LPI’s engine is architected to have the following unique properties:
- High fuel efficiency of 57% at peak, and 50% at part-load
- High power density of 1 Hp / Lb
- Simple design with low part count
- Multi-fuel capable: diesel, JP8, gasoline, natural gas, bio-fuels
- Low noise: the engine has low pressure exhaust and no poppet valves
The conventional internal combustion engine typically only converts ~ 30% of the energy in the fuel to mechanical work. For applications where engine loads vary, the efficiency can drop to as low as 1% efficiency (during idling, for example), and automotive engines are only 15% efficient over typical driving conditions. In the best case, ~30% of the chemical energy of fuel is converted into useful work; ~40% is removed as heat by cooling, and another 30% is lost with exhaust gases.
There are several different types of engines in operation today, and each has its own advantages. The High Efficiency Hybrid Cycle engine is able to combine the benefits of these existing and proven technologies.
Proceed to information about how the cycle works, or jump ahead to see an animation of the engine.
