In certain implementations, a ship propulsion system includes: at least one internal combustion engine with: a combustion chamber for burning a fuel; an intake tract for supplying fresh air to the combustion chamber; and a turbocharger with a compressor in the in-take tract; an electrolysis device for producing hydrogen gas for the internal combustion engine and for producing oxygen gas; an alcohol tank for supplying alcohols to the internal combustion engine; and a water tank, wherein the water tank and the alcohol tank are connected to the combustion chamber or a pressure side of the compressor for the supply of water and alcohol into the intake tract, and wherein the electrolysis device is connected to the pressure side of the compressor for supplying hydrogen gas into the intake tract or connected to the combustion chamber for supplying hydrogen gas into the combustion chamber.

A system includes a reciprocating expander including: a piston disposed in a chamber; a crankshaft; a connector rod coupled between the piston and the crankshaft and configured to transfer torque to the crankshaft in response to movement of the piston in the chamber; and a fluid inlet and a fluid outlet on one side of the piston. The system also includes a first flowpath coupled between a wellbore and the reciprocating expander and configured to communicate gas from the wellbore into the fluid inlet of the reciprocating expander at a first pressure. The system further includes a second flowpath coupled between the reciprocating expander and downstream equipment and configured to communicate the gas from the reciprocating expander toward the downstream equipment at a second pressure, the second pressure being lower than the first pressure.

A system includes a reciprocating expander including: a piston disposed in a chamber; a crankshaft; a connector rod coupled between the piston and the crankshaft and configured to transfer torque to the crankshaft in response to movement of the piston in the chamber; and a fluid inlet and a fluid outlet on one side of the piston. The system also includes a first flowpath coupled between a wellbore and the reciprocating expander and configured to communicate gas from the wellbore into the fluid inlet of the reciprocating expander at a first pressure. The system further includes a second flowpath coupled between the reciprocating expander and downstream equipment and configured to communicate the gas from the reciprocating expander toward the downstream equipment at a second pressure, the second pressure being lower than the first pressure.

A high efficiency steam engine or steam expander includes a cylinder, cylinder head and piston in which cylinder clearance volume is zero or nearly zero together with a negligible amount of compression such that any pressure in the cylinder clearance volume just before the power stroke is as low as ambient pressure or condenser pressure to provide superior thermal efficiency in a compact compound engine having a high pressure expansion chamber within the piston and low pressure chamber in the cylinder. The inlet valve is opened slightly by piston movement and a steam assist force then drives it to its fully open position. Steam passes from the high pressure chamber to the low pressure chamber through a transfer valve located in the head of the piston and steam is released through an automatic exhaust valve in the cylinder head.

A mechanically simplified electric and fluid (gas, vapor or liquid) control for a piston engine, including an engine valve actuator system that eliminates rotating cam shafts and heavy internal combustion engine valve closing springs by using an electromagnet and an armature which is attracted by the electromagnet to initiate movement of both a fluid control valve and the engine valve. When the control valve is moved only slightly off its seat by the armature, fluid pressure instantly drives the control valve a much greater distance closing the engine valve. Opening and closing time is regulated independently. Engine valves are opened by reversing the fluid pressure balance across the control valve at the time selected.

A modular internal combustion engine (10) comprising a cam crank (74) having a piston stroke guide pattern (76) to control the stroke motion profile of the piston (70), which can be expanded by replacing the crank shaft (22) with a longer crank shaft (22), and installing a supplemental engine block (18) with a supplemental cam crank assembly (75).

A modular internal combustion engine (10) comprising a cam crank assembly (75) having a cam crank (74), an intake cam (90) and an exhaust cam (92), the cam crank (74) having a piston stroke guide pattern (76) to control the stroke motion profile of the piston (70), which can be expanded by replacing the crank shaft (22) with a longer crank shaft (22), and installing a supplemental engine block (18) with a supplemental cam crank assembly (75).

A modular internal combustion engine (10) comprising a cam crank assembly (75) having a cam crank (74), an intake cam (90) and an exhaust cam (92), the cam crank (74) having a piston stroke guide pattern (76) to control the stroke motion profile of the piston (70), which can be expanded by replacing the crank shaft (22) with a longer crank shaft (22), and installing a supplemental engine block (18) with a supplemental cam crank assembly (75).

In certain implementations, a ship propulsion system includes: at least one internal combustion engine with: a combustion chamber for burning a fuel; an intake tract for supplying fresh air to the combustion chamber; and a turbocharger with a compressor in the in-take tract; an electrolysis device for producing hydrogen gas for the internal combustion engine and for producing oxygen gas; an alcohol tank for supplying alcohols to the internal combustion engine; and a water tank, wherein the water tank and the alcohol tank are connected to the combustion chamber or a pressure side of the compressor for the supply of water and alcohol into the intake tract, and wherein the electrolysis device is connected to the pressure side of the compressor for supplying hydrogen gas into the intake tract or connected to the combustion chamber for supplying hydrogen gas into the combustion chamber.

A compressed gas engine is provided. The compressed gas engine may include a first crankshaft, a first set of piston assemblies, a second set of piston assemblies, and a first valve assembly. The first set of piston assemblies may be coupled to the first crankshaft and comprise a first piston assembly having a first diameter and a second piston assembly having a second diameter. The second set of piston assemblies may be operatively coupled to the first crankshaft and comprise a third piston assembly having the first diameter and a fourth piston assembly having the second diameter. The second set of piston assemblies may be positioned on the crankshaft opposite the first set of piston assemblies such that the piston assemblies of the first set of piston assemblies and the piston assemblies of the second set of piston assemblies having the same diameter are aligned.