CHENEY WARNS U.S. ON ENERGY AP-NY-03-21-01 1946EST Washington (AP) - Vice President Dick Cheney warmed Wednesday that the United States must generate more of its own energy or the country risks power shortages like those in California, but on a national scale. Cheney cited estimates that the United States will need 1,300 new power plants over the next 20 years - roughly 65 each year to have adequate generating capacity. Plus, he said those plants will need other infrastructure, such as a means of obtaining the coal or gas and transmission lines. "Our infrastructure in the energy area is very...