TY - BOOK ED - United States. General Accounting Office TI - Electricity supply: the effects of competitive power purchases are not yet certain U1 - 333.793 PY - 1990/// CY - Washington PB - GAO KW - Empresas Eléctricas KW - Energía Eléctrica KW - Estados Unidos N1 - 02430; This report examines electric utilities use of competitive bidding to purchase electricity from nonutility generating sources and identifies how such purchases might affect the reliability and cost of electric power ER -