The history of the Stirling Engine

The history of the Stirling Engine

The history of the Stirling Motor
A small Historic Peek


Historischer StirlingmotorThe first Stirling motor was patented by the Scottish intellectual, Robert Stirling. The first machine worked as a water pump for draining a flooded quarry in Scotland. At that time in history, boiler explosions in steam engines were relatively common-place. Stirling wanted to make work in the quarries and coal mines safer. The influx of warmth could be controlled well, and the relative low pressure in the machine could not lead to serious accidents. Other than the bettered safety conditions, the motor was found to have lower fuel consumption, compared to the steam engine, which played a roll in the development of this new technology.

At the beginning of the 20th century, about 250,000 Stirling motors were in use world-wide as table-top fans, water pumps and engines for small apparati like sewing machines. Thus, the private house hold and small manual labor operations were supplied with mechanical energy. When Otto, diesel, and electric motors became more and more popular, Stirling motors were forced off the market.

Stirlingmotor als Kältemaschine für TieftemperaturtechnikAn unending domain of Stirling motors is the production of very low temperatures. With minimal temperature Stirling cryomachines, temperatures down to 80 K (ca. -193°C) (Explanation Kelvin) can be reached. Air or methane condensation and cooling of infrared sensors are typical examples for low temperature utilization. The military has been producing these machines in large numbers for years, since it needs many cooling units for automatic weapons and infrared visors.
In recent times, Stirling motors have a novel use in solar thermal units, e.g. in the Spanish Almeria, where a dish/Stirling was put into use in tandem with the German Center for Air and Space Travel (DLR). Even in warm parts of Germany, the summer sun in the afternoon provided a performance of 1000W per m2.


Solarkraftwerk mit StirlingmotorenDish/Stirling systems are made of a parabolic concentrator, a receiver, and a Stirling motor with a coupled generator. In comparison to large units like solar towers and parabolic rim fields (50 to 200 MWe), dish/Stirling systems are designated for decentralized uses of quite a few kW up to a few MW of electrical performance. The modular size is between 5 kWe and 25 kWe in present systems. Through very high concentration factors and temperatures, dish/Stirling units reached a 29 % of the highest conversion level of the best solar thermal unit.
Dish/Stirling systems can be ideally used in regions without electricity for supplying electric energy, water, desalination etc. or as a supplement to existing electrical supply. When individual modules are linked to form the size of a park, they produce 5-10 MW.

Block-type thermal power stations have become increasingly interested in Stirling models, because they represent alternatives to heating and energy supply down to the private household.