Hokkaido Electric Power Co, Inc. or HEPCO, is a Japanese electric utility that serves the northernmost island of Hokkaido. HEPCO is involved in the generation, transmission, and distribution of electric energy on the island. The company utilizes a portfolio of hydroelectric, steam, gas, internal combustion, nuclear, geothermal, and solar power plants to do this. While most of HEPCO's sites are hydroelectric, the company's fossil fuel facilities represent the vast majority of its total energy production and production capacity. Hokkaido Electric Power's electric utility business is responsible for nearly all of its revenue with sales split mainly between residential and commercial/industrial customer groups. Most electrical output, however, is transmitted to residential customers.