An energy charging apparatus includes an energy charging unit charging green energy in an energy saving apparatus, a measured amount information acquisition unit acquiring measured amount information that indicates a charged amount of green energy measured by the energy saving apparatus from the corresponding energy saving apparatus, and a certificate issuance unit issuing a certificate for certifying an amount of green energy charged in the energy saving apparatus when a charged amount of green energy charged by the energy charging unit coincides with the charged amount of green energy shown in the measured amount information, wherein the certificate is managed in association with the energy saving apparatus and is discarded if the amount of green energy that is certified by the corresponding certificate is output from the energy saving apparatus.