The First Major Disruption to Engine Tech in 100 Years

Our patented technology improves the typical combustion engine across efficiency, weight, size, vibration, and noise. We’ve developed two game-changing engine technologies that deliver up to 10X the power-to-weight of legacy engines with just two primary moving parts.

TRADITIONAL ENGINES ARE INCREDIBLY INEFFICIENT. WE ASKED OURSELVES WHY?

LPI has developed two core technologies: a patented thermodynamic cycle and our patented X-Engine.

XTS-210 vs. comparable piston diesel engine

Liquidpiston Innovations

X-Engine vs. Wankel

Our patented X-Engine solves the problems of the rotary engine without sacrificing the benefits. It’s simple – it has only 2 moving parts, practically zero vibration, extremely compact and lightweight; and can run on heavy fuel, gasoline, and even gaseous fuels like propane and hydrogen.

Wankel

X-Engine

We turned the traditional Wankel inside out. Traditional Wankels have a triangular rotor in a "peanut" shaped (trochoidal) housing. We have a peanut-shaped (trochoidal) rotor within a tri-lobed-shaped housing. By turning the rotary "inside out", the X-Engine has stationary apex (tip) seals that can be directly lubricated. Furthermore, the long, skinny, rotating combustion chamber of the Wankel becomes a stationary combustion chamber within the housing that can be optimized for better fuel-air mixing and combustion. In this way, we address many of the challenges of the old Wankel rotary including sealing, cooling, lubrication, emissions, and efficiency.

Our Patented Thermodynamics

We patented our High-Efficiency Hybrid Cycle (HEHC) which makes our engine’s up to 10X better power-to-weight ratio possible. Here’s how it works:

High Compression Ratio (i.e. Diesel cycle): For maximum efficiency, air is compressed to a high compression ratio, fuel is injected and compression is ignited (CI-HEHC). Our initial prototype - the "X-Mini" - utilizes a spark-ignition (SI-HEHC) version of the cycle with a lower compression ratio standard for gasoline engines. The advantage of SI-HEHC is compatibility with a range of fuels including Diesel, gasoline, jet fuel, propane, and even hydrogen

Constant-Volume combustion (i.e. Otto cycle): A dwell near top-dead-center (TDC) allows more time or fuel-air mixing and forces combustion to occur at nearly constant-volume conditions.

Over-expansion (i.e. Atkinson cycle): Combustion products are over-expanded using a larger expansion volume than compression volume, as in the Atkinson Cycle.

Cycle-skipping power modulation may also be utilized, which allows high efficiencies at low power settings while simultaneously cooling the engine’s walls internally and providing partial heat recovery.

Lightweight & Compact

Up to 80% smaller and lighter than the traditional piston Diesel engines.

Simplicity

Only two primary moving parts, optimally balanced.

High-Efficiency and Lower Fuel Consumption

The optimized thermodynamic cycle has the potential to decrease fuel consumption by 30%, thereby lowering CO2 emissions and the cost of running an engine

Quiet and Near-Zero Vibration

With lower pressure exhaust and just two moving components that are optimally balanced, the engine is inherently quiet, and offers exceptionally low vibration.