The discussion centers on finding the cheapest low-power diesel engine, specifically a 3 kW engine for a college project. It highlights the challenge of sourcing affordable small diesel engines due to the high cost of precise fuel injectors, which are essential for their operation. Portable multi-fuel generators used by the military are suggested as potential options, though they may be found only through surplus auctions. The smallest readily available units are larger generators, with prices starting around $10,000 for 15 kW models. For smaller engines, options like a 6 hp diesel engine can be found online for approximately $500 to $300.