A primeira forma de energia que o homem utilizou foi o esforço muscular (humano e de animais domesticados), a energia eólica (vento), e a energia hidráulica, obtida pela corrente dos rios. Posteriormente, com a Revolução Industrial, na segunda metade do séc. XVIII e no séc. XIX, surgem as modernas máquinas, sendo as fontes de energia mais utilizadas a madeira e o carvão.
No século XX, com a invenção do motor de explosão, o petróleo começou a ser o principal recurso energético.
Actualmente, os recursos energéticos que podem ser utilizados pelo homem são de dois tipos: não renováveis e renováveis.
Os combustíveis fósseis (petróleo, carvão e gás natural) são recursos não renováveis isto é, um dia se esgotarão completamente; eles também são muito poluidores, pois o seu uso implica muita poluição do ar. Por esses motivos eles estão actualmente em declínio, em especial o petróleo. Assim, o Homem teve a necessidade de encontrar energias alternativas para suprimir as suas necessidades e eliminar os problemas ambientais. Das alternativas possíveis são a energia eólica, solar, hidroeléctrica, geotérmica, marés, ondas, biomassa e biogás.
As fontes de energia estão ligadas ao tipo de economia: quanto mais industrializada ela for, maior será o uso de energia.
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