To solve the problem of the difficulty of setting an estimated price of energy-saving equipment into a market price while assuring an energy-saving improvement efficiency an electric power demanding person desires.

This energy saving evaluation system is provided with a CTI 1e for inputting consumption energy amount data for a power demanding person 3B who introduces cogeneration equipment 3b, an equipment data storing means 1a for storing corresponding data between the saving-energy improvement efficiency and compensation of the cogeneration equipment 3b, and a calculating means 1d for calculating the compensation of the cogeneration equipment 3b, based on the consumption energy amount data and the corresponding data.