An object of the invention is to predict energy consumptions of a vehicle, using geographic characteristic values which are independent from particular driving patterns and vehicle parameters and unique to respective links. A navigation server predicts energies which are consumed when a vehicle runs on links. The navigation server calculates geographic characteristic values of respective links, the geography of the each link affecting the consumption energy with the geographic characteristic values, the calculation being based on energy consumptions collected from probe vehicles, and calculates predicted energy consumption of each link selected as a processing target, based on the geographic characteristic values. A navigation terminal obtains these predicted energy consumptions and performs route search with the obtained predicted energy consumptions as costs.