The invention relates to a method for improving the efficiency of a combustion engine. The method comprises measuring a quantity of a primary fuel supplied to the combustion engine. Determining an operating state of the combustion engine. Selecting a fuel mapping profile based on an operating state of the combustion engine and determining from the fuel mapping profile an amount of a secondary fuel to be injected as a fraction of the measured quantity of the primary fuel.

A bi-fuel refrigeration system and method of retrofitting a refrigeration system for the same. The system includes an engine in energy supplying relation to a refrigeration unit, said engine running off a constant predetermined amount of gaseous fuel and a variable amount of distillate fuel. An electronic control unit generates control signals to dictate the ratio of gaseous to distillate fuel is used by the engine. An actuator is structured to provide isochronous control of the system, and is accordingly disposed in flow adjusting relation to the distillate fuel intake to variably adjust the amount of distillate fuel injected into the engine. The method of retrofitting includes at least inserting a gaseous fuel supply and mixer into the air supply line, inserting an electronic control unit for isochronous control of the system, and inserting an actuator for isochronous control of the amount of distillate fuel used in the system.

A device, and associated methods, for converting a fuel-injection engine, originally intended for use with a first fuel, allow the engine to operate with a different, second fuel (e.g., bioethanol, alone or mixed with unleaded fuel(s)). The device delivers an adapted injection signal to an injector based on an original injection signal (SI) received from an engine control unit. An analyzing, circuit includes a measuring circuit, to measure the SI; a detecting circuit, to detect an end time of the SI when the measured signal drops below an end threshold; and an updating circuit, to update a value of the end threshold, depending on the measured signal. A signal generator produces a complementary injection signal (SC) starting from the end time. A switching circuit transmits the SI to the injector, then delivers the SC to the injector. The SI and the SC together form the adapted injection signal.

Techniques, systems, and devices are disclosed for converting an alcohol and water mixture to hydrogen-rich gas inside a gasoline engine to power the gasoline engine vehicle. In one aspect of the disclosed technology, an electronic control module installed on a gasoline engine vehicle for controlling the gasoline engine vehicle to run on an alcohol and water mixture as fuel is disclosure. This electronic control module includes a processor, a memory, and an interface coupled to the ECU of the gasoline engine vehicle to receive various sensor signals from the ECU. The electronic control module also includes interconnects coupled to various modules of the gasoline engine vehicle to control a process of running the vehicle on the alcohol and water mixture stored in the gasoline tank of the vehicle. The said process includes converting catalyzed alcohol and water mixture to a hydrogen-rich gas inside a cylinder of the gasoline engine.

A hydrogen-diesel direct injection dual-fuel system for an internal combustion engine enables retrofitting to existing diesel engines. The system comprises: a cylinder head of the engine having a first and a second injector hole; a diesel pilot injector positioned in the first injector hole; and a hydrogen injector positioned in the second injector hole; wherein the hydrogen injector comprises: a gasoline direct injector having an external shank and a distal output end; and a nozzle cap covering the distal output end, wherein the nozzle cap is welded to the external shank.

A bi-fuel control system can include an electronic control module and a control unit that are in communication with each other. The system can include a first set of fuel injectors that are configured to deliver a primary fuel to an engine and can include a second set of fuel injectors that are configured to deliver a secondary fuel to the engine. The bi-fuel control system can operate in either a primary operational state in which the first set of injectors is used or a secondary operational state in which the second set of injectors is used. In either operational state, the electronic control module can control the respective set of injectors independently from the control unit.

A method for operating an internal combustion engine includes a step of providing an oxygen-containing gas having greater than 22 volume percent oxygen and combining the oxygen-containing gas with a fuel to form a combustible mixture. The combustible mixture is provided to an internal combustion engine wherein combustion of the combustible mixture drive the internal combustion engine. An internal combustion system executing the method is also provided.

A hydrogen-diesel direct injection dual-fuel system for an internal combustion engine enables retrofitting to existing diesel engines. The system comprises: a cylinder head of the engine having a first and a second injector hole; a diesel pilot injector positioned in the first injector hole; and a hydrogen injector positioned in the second injector hole; wherein the hydrogen injector comprises: a gasoline direct injector having an external shank and a distal output end; and a nozzle cap covering the distal output end, wherein the nozzle cap is welded to the external shank.