Air start steam engine

A method for operating an engine responsive to selective supply of two different pressurized gaseous working fluids to at least one chamber of said engine wherein the pressurized gaseous working fluids can expand, causing said engine to produce power, comprising the steps of:

• providing a supply of a first pressurized working fluid which is gaseous at ambient temperature;
• providing a supply of a second working fluid that is liquid at ambient temperature, and which can be heated to form a supply of a second pressurized gaseous working fluid;
• providing a controller which monitors the amount of power that an operator requests be produced by the engine, and performs the following steps in response to an operator's request that the engine produce power:
• if said engine has not been started, starting said engine by supplying said first pressurized gaseous working fluid to said at least one chamber of said engine, causing said engine to produce power;
• supplying said second working fluid to a boiler in liquid form;
• applying heat to said boiler to convert said liquid second working fluid to a second pressurized gaseous working fluid;
• and
• when said second pressurized gaseous working fluid is available, providing said second pressurized gaseous working fluid from said boiler to said at least one chamber of said engine wholly or partially in lieu of said first pressurized gaseous working fluid, causing said engine to produce power;
• and
• during operation of the engine, monitoring the operator's request for power and determining the appropriate amounts of the first and second working fluids to be supplied to said engine.

A vehicle power system comprising:

• a first fluid storage tank storing a first working fluid which is gaseous at ambient temperature in a gaseous state under a pressure substantially greater than ambient pressure;
• a second fluid storage tank storing a second working fluid which is in a liquid state at ambient temperature;
• a heater coupled to at least said second fluid storage tank, and configured to heat said second working fluid to a temperature above a vaporization temperature of said second working fluid, forming a second gaseous working fluid;
• an engine configured to controllably receive said first gaseous working fluid from said first fluid storage tank and to controllably receive said second gaseous working fluid from said heater, whereby said first and second gaseous working fluids expand in at least one chamber of said engine, causing said engine to produce power;
• and
• a controller responsive to an operator request for controlling heating of said at least second working fluid in said heater, and flow of said first and second working fluids from the respective vessels to the heater and to said at least one chamber of the engine,
• whereby said controller repeatedly monitors the operator's request for production of power by said engine, and determines the relative amounts of first and second working fluids to be supplied to the engine responsive thereto.