PROBLEM TO BE SOLVED: To roast raw materials such as seeds by effectively using waste heat from a power engine.SOLUTION: The power generating system 1 uses the power engine including: a roasting device 11 for roasting raw materials； an oil extracting device 21 for extracting a fuel from the roasted raw materials； a diesel engine 62 for obtaining the power by combusting the extracted fuel； and a power generator 69 for generating the electricity with the power of the diesel engine 62. The roasting device 11 roasts the raw materials by heating the raw materials with the waste heat of the diesel engine 62, and includes an exhaust distribution part 111 for distributing the exhaust discharged from the diesel engine 62 therein and a raw material holding part 112 for holding the raw materials for the heat-exchange with the exhaust.
