Kampala - Uganda's 250-megawatt Bujagali hydropower project started supplying electricity to the national grid and may reach 50 megawatts later today, Energy Minister Irene Muloni said.  Supply to the national grid will gradually rise with commissioning of the entire capacity expected in July, Muloni said today by phone from the capital, Kampala.  "They started testing the plant last week and supply reached 37.5 megawatts this morning and may reach 50 megawatts by the end of the day," she said.