Kilowatt-Hour per Unit of Fuel. The energy value of a unit of fuel depends on its mass, carbon and hydrogen content, and the ratio of carbon to hydrogen. In general, hydrogen generates approximately 62,000 BTU per pound and carbon generates around 14,500 BTUs per pound.
Quick Answer. The three largest rivers in Portugal are the Tagus River, the Douro River and the Guadiana River. All three rivers also flow through Spain. The largest river in Portugal is the Tagus River; it is 645 miles long. Continue Reading.
The numerous mountain ranges in Portugal include Serra da Estrela, Serra da Gardunha, Serra da Malcata, Serra de Monchique, Serra de Montesinho, Serra de Sintra, and Sierra de la Culebra. 1. Serra da Estrela is in the Central Region.