Nowadays the rapid growth of mobile traffic has attracted researchers' attention on the power efficiency problem in the Internet. Given the outstanding advantages of "edge cache" in content delivery services, researchers are attempting to apply this idea to reducing network power consumption. However, the power efficiency issue in the existing works is mainly researched under the background of the access networks and lack of in-depth analysis from the perspective of the cooperation between content providers (CPs) and Internet Service Providers (ISPs). Therefore, we design an edge cache-assisted power-efficient data transmission scheme in mobile wireless environments, where the power consumption problem of ISPs and CPs is formulated as a centralized model. Besides, we theoretically analyze this power efficiency model to optimize cache allocation and content distribution. Simulations are conducted in the different network scenarios and the simulation presents that the performance of the proposed minimal power model exceeds that of the current Internet solutions without deploying edge caches in the wireless networks.