The web search results mention the historical development of the East and West in China, with one source noting the government promoted collaboration between the industrialized east and lesser-developed western regions. However, no source explicitly states that for *decades*, the western regions *primarily functioned* as energy suppliers to the east, making it a single-source assertion based on the provided context.

Two web search results discuss the high energy consumption of data centers and the potential for electricity costs to rise due to them. However, none of the provided evidence explicitly quantifies that electricity accounts for *more than half* of the costs in data center operations. The claim is strongly implied by the focus on energy demand, but not directly quantified by the sources.