An electric houseboat comprises a hull and a house-like structure mounted on the hull which includes at least one bedroom, a bathroom, and a kitchen. A Diesel generator comprises the sole power source for the houseboat. The operating temperature of the Diesel generator is controlled by directing coolant through the Diesel generator and through a keel pipe which extends along the hull of the houseboat thereby discharging heat into the water over which the houseboat operates. Exhaust resulting from operation of the Diesel generator is directed upwardly and is discharged at a point substantially above the water and above the house-like structure of the houseboat.