I have about 35 ceiling- mounted heat pumps throughout the building, and it would be cost-prohibitive to install a separate meter on each one. Each of the top 2 floors has an electrical panel dedicated to servicing 10 heat pumps on each those floors. These 20 units easily reach the 40% btu load of the building. Can i satisfy the system submetering goal by installing one meter on each of these electrical panels, thereby capturing energy use of only those 20 heat pumps? In other words, do I need to install a separate meter for every heat pump in the building? or how about every heat pump on the top 2 floors?