1952 Philips 102C Stirling Engine Genset

1952 Philips 102C Stirling Engine Genset 

 (Also called the MP 1002CA and the Type 10)                             

Bore: 55mm, Stroke 27mm, Swept volume: 64cc

Working fluid: air at 10 bar

Electrical output 200watts at 1500rpm

  Decline of the Stirling Engine

    As the internal combustion engine and the electric motor gained popularity in the late 1800’s, development of bulky, heavy and inefficient Stirling engines almost completely stopped.

Rebirth

   During the 1930’s Philips, the Dutch electrical goods manufacturer, needed a compact and quiet portable generator to power their electricity-hungry valve radios.  They chose to resurrect the Stirling engine for this application- largely because it could be quieter.   Unlike most 19th century Stirling engines, which were unpressurised, their design for this generator uses an external continuous flame to heat pressurised air inside the sealed engine.  Pressurisation substantially increases specific output (power per swept volume) and enables higher efficiency.  Unlike Otto (petrol) and Diesel internal combustion engines that periodically draw air and fuel into the engine cylinder and noisily exhaust the combustion products, it’s whisper quiet.   

Secretive Development

    Philips worked on Stirling engine development in secret during World War II while the Netherlands was under German occupation.  Research continued after the war aimed at developing a genset that would be quiet, reliable, low-maintenance- and run primarily on kerosene, which was inexpensive and generally available during this time of petrol rationing.  In 1951, Philips put the 102C into production with an initial batch of 250 but soon realised they could not be made for a competitive price and only 150 (approx.)  were completed.  The 1947 invention of the transistor that cut power required for radios to a level that could supplied by batteries, didn’t help either.   One use was during the 1953 North Sea inundation (Zeeland Floods) in the Netherlands, when Philips supplied 102C gensets for emergency radio communication and lighting in isolated areas.  This unit is one of a few that were then distributed to museums and universities (it came to Christchurch’s Canterbury University). 

Defining features

Quiet and Smooth: Unlike petrol or diesel engines, the 102C produces minimal noise and vibration.

Compact and Efficient: The Stirling cycle enables effective fuel energy to electricity conversion.

Reliability: Designed for long-term operation with minimal maintenance.

Legacy

    Whilst the 102C was never manufactured in volume, Philips’ Stirling engine development did inspire further research, with considerable effort applied to developing Stirling engines for cars and trucks in the 1970’s- largely driven by concerns about emissions.  These did not become commercially viable either but resulting widespread interest in the Stirling cycle led to other applications.  Examples of these are the Fabrum cryocoolers and the WhisperGen micro-cogeneration systems in this collection- both developed and manufactured in Christchurch.

    The Philips 102C demonstrates an alternative path in engine development—one that prioritises efficiency, low maintenance and reliability, principles that remain relevant in today’s energy landscape.

Don Clucas for the Mahan Heritage Centre, June 2025