SPL, dị ka China ekwupụta unit ụlọ ọrụ substation, nwere ike ịnye ndị ahịa ụwa anyị ọnụ ala na nke dị elu. E wezụga inye a pụrụ ịdabere na ya ekwupụta unit substations, anyị bụkwa ndị ọkachamara na ahia mba ụwa, na ikike nke idozi nsogbu ọ bụla na ọganihu nke mbupụ mbupu.