battery 440 a current soc of the battery 440 and an average cost spent for charging the battery 440 especially the current soc of the battery 440 may be expressed as a percentage the hccs 300 determines a recommendation control content list by using the collected information in operation s 923 at this point the collected information may include at least one of information on the battery 140 of the ev 100 information on the battery 440 of the hps 400 and information on a power policy the recommendation control content list includes at least one recommendation control content each recommendation control content may include part or all of a price a power source a power sink a control time and a power amount the price at this time may be a cost or a profit if the recommendation control content includes all of a price a power source a power sink and a control time this may mean that the power of the power source corresponding to a corresponding power amount transfers to the power sink at the control time with a corresponding price for example if the power source is the power supply facility 600 the power sink is the ev 100 the control time is 13 hr the price is 1 and the power amount is 1 wh this means charging the ev 100 with a power of 1 wh from the power supply facility 600 at a cost of 1 at 13 00 if the power source is the ev 100 the power sink is the power supply facility 600 the control time is 13 hr the price is 1 and the power amount is 1.