Making Stirling efforts

Materials World magazine
3 Aug 2015
An unidentified technician with Fred Starr, Ray Pinchin, Tony Choy and Dr Gordon Smith and the Stirling engine micro cogeneration prototype in the mid 1990s.

Fred Starr recollects...

Scanning through the articles on alternative energy in the June issue of Materials World, I was surprised to read no mention of distributed power, an essential feature of the hydrogen economy. In such a scenario, every household would generate its own electricity from a fuel cell, with the waste heat being used in the central heating system. Sadly, the fuel cell and the hydrogen economy always seem to be just around the corner. Even sadder, if some people had shown less self-interest, Britain could have been a world leader in distributed power. 

Back in 1987, I took the lead in introducing it to British Gas. The concept was to incorporate a Stirling engine within a gas boiler, whereby the engine not only generated power, but the heat from the engine cooling water supplied the central heating. It promised to revolutionise UK power generation. But it took my team five years for it to be accepted as an R&D Flagship.  

From whither did this inspiration come, for what came to be called micro cogeneration? It began when Grev Gibson, as an Assistant Director at our Research Station down in London, decreed that all work on coal gasification processes must stop. It left me with the prospect of a very early retirement! Gibson would, however, support novel uses of natural gas for power generation. There was, then, a way through. Materials we had been testing in our gasifier work had the temperature capability to allow Stirling engines to work more efficiently. Stirling engine micro-cogeneration would increase our sales of gas, cut overall energy bills, and reduce global warming. Grev gave me all the support he could, although he was working against British Gas policy that we should not get into electricity generation.

The first ever Flagship was built by Moses. When construction of the Ark began, it was greeted with derision. Once the rain began to fall, it was a different story. So it was in British Gas R&D. Having completed the North Sea Gas revolution, what was left for my colleagues? Virtually every house had central heating. We knew all we needed to know about gas transmission and distribution and we had so much natural gas that work on coal gasification could be shelved indefinitely. Stirling engine CHP was not just a flagship. It was a lifeline to those whose future suddenly seemed bleak. Everyone, it seemed, wanted to be on board.

But the vessel was not even half built. Our efforts in London had been run on a shoestring. Testing Stirling engine prototypes was exceedingly costly. I also needed to sponsor work to ‘harmonise’ a small generator with the electricity network. The photo shows a group of us, including Gordon Smith and his technician from Leicester University, beaming with pleasure at the first successful run of a Stirling engine-harmoniser combination. Owing to privatisation and the enforced breakup of the company by the Gas Regulator, R&D was in a spin and short of money. Time was wasted in trying to bring in partners to help fund the development as well as commercialise the venture. 

By 1996, the programme was nothing like I had imagined, and could see this hand-to-mouth existence dragging on. My last effort was to write a specification for a 1.1kW concept before I departed to greener fields. In 2012, 25 years after I started the project, Baxi began to sell the Eco-Gen boiler, based on a free piston Stirling, essentially a descendent of the yellow cylinder shown in the photo. Sales are sluggish, I understand. We now live in a world where it’s harder to justify the type of device.

Could things have been different? Undoubtedly! For a fraction of the investment that has gone into nuclear power, a production line could have been built. The Government could have done as it did with the condensing boiler, in legislating that all new boilers be of the micro cogen type. Then again, energy policy in the UK has never been of sterling quality, not even when faced with a Stirling idea!