what is the smallest diesel engine commercially available? do you know?
The smallest one I’ve ever seen in a car is a 0.75L turbodiesel in a European smart car, and of course, we can’t buy it here.
There are small diesels on eBay from China, but I don’t think that these are built to stationary/industrial specifications - they are more for lawn equipment, etc.
Pretty darned small. Years ago, I read a story about model airplaners, and it said that the Soviet model airplane clubs used Diesel engines to power their planes, because the lighter hydrocarbon fractions normally used for model plane engines were not easily available, but that diesel was.