You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Kenya

Context:
The largest share of Kenya's electricity supply comes from hydroelectric stations at dams along the upper Tana River, as well as the Turkwel Gorge Dam in the west. A petroleum-fired plant on the coast, geothermal facilities at Olkaria (near Nairobi), and electricity imported from Uganda make up the rest of the supply. Kenya's installed capacity stood at 1,142 megawatts between 2001 and 2003. The state-owned Kenya Electricity Generating Company (KenGen), established in 1997 under the name of Kenya Power Company, handles the generation of electricity, while Kenya Power handles the electricity transmission and distribution system in the country. Shortfalls of electricity occur periodically, when drought reduces water flow. To become energy sufficient, Kenya aims to build a nuclear power plant by 2017.

Question:
Where does the largest part of Kenya's power come from?

hydroelectric stations at dams