Portable electricity generator. The generator (right) uses a petrol engine (left). Petrol, a fossil fuel, is burnt in the engine, and the power from the engine operates a dynamo in the generator which produces electricity. Because a petrol engine is involved, exhaust gases will be produced, making this a potential carbon monoxide (CO) hazard. To avoid poisoning from CO fumes, petrol-driven generators should be operated in a well-ventilated area. This is a GX 120 4.0 engine from Honda. It is started by pulling an ignition cord (handle at centre left).