Uses of the ST-5
The ST-5 has been designed forlong periods of stationary use for residential and small-scaleagricultural and industrial purposes. Any application whichrequires a long life prime mover and continuous hours ofoperation is a good candidate for the ST-5. Recommended uses areelectricity generation, water-pumping and powering of small scaleimplements, compressors, etc.
The ST-5 is ideal forpowering a rotary electric generator producing up to 3.5 kW ofelectricity, either AC or DC. The engine has been designed sothat it can operate at full output for extended periods of time.This is why the ST-5, despite being only a 5-plus hp prime mover,is sufficient for a 3 kW generator which would use a 7 or 8 horsepower IC engine to power it. The engine's speed is governed tooperate at 650 RPM so that the electric frequency can bemaintained at 60 hertz, but slight variations are inevitable. Avoltage regulator would be required for appliances such astelevision sets and computers. Incorporating the ST-5 into agen-set configuration requires a radiator, an engine-drivenradiator fan and a suitable generator matched to the engine withpulleys, belts or gears to provide for required frequency output.Examples of the appliances which can be operated with 3kW of electricity,along with the constant and surge (starting) loads for each areshown below.
Note: These areaverages. Check your equipment for exact wattage. The startingloads on some equipment may be considerably higher. Check yourequipment for individual starting loads.
For water pumping, the ST-5requires only a suitable centrifugal water pump, as the coolingfor the engine is supplied by the water being pumped. The amountof water pumped will depend on the efficiency of the pump and onthe depth from which the water is pumped. The graph below assumesthat the water pump is 60% efficient; i.e. 60% of the 5 hp putout by the engine is converted into pumped water.
Compressors, small machinessuch as shredders, log splitters and grinders, like thegenerator, require the addition of a radiator and fan, andpulleys or gears to match the engine speed to the load. Amongapplications currently being examined are oil jacks for wellsless than 3,000 feet in depth where the ST-5 runs directly offthe impure natural gas or crude oil found at well sites, a smallscale rice milling system using part of the waste husk as fueland small scale milk condensing plants, utilizing the heatfrom the engine as well as the mechanical power.
click here to view a jpeg of a Stirling engine run rice mill in India
Useable Heat - A Stirling Phenomenon
The burner of the ST-5behaves like a high quality biomass-burning stove. As a result, atremendous amount of clean heat is available for use. In additionto the burner heat which is easily recovered, the cooling waterof the engine also provides useable heat.
By the use of simple heatexchangers, this heat can be used for space heating of your house,dairy or greenhouse as well as supplying your domestic hot waterneeds. At full output, the engine produces over 25kW ofrecoverable heat - far in excess of the needs of an average house.
The ST-5 makes cogeneration - recovering this heat for space anddomestic water heating while simultaneously generatingelectricity - practical.
