Santosh Devi is [a] 19-year-old, semi-literate woman from the backwaters of Rajasthan [who] has broken through India's rigid caste system to become the country's first Dalit solar engineer. While differences of caste have begun to blur in the cities, in rural India Dalits - also known as untouchables" - are still impoverished and widely discriminated against. Santosh trained to be a solar engineer at the Barefoot College in Tilonia, 100km from Jaipur. The college was set up in 1972 by Sanjit "Bunker" Roy to teach rural people skills with which they could transform their villages, regardless of gender, caste, ethnicity, age or schooling. The college claims to have trained 15,000 women in skills including solar engineering, healthcare and water testing. Roy, 65, says his approach - low cost, decentralised and community driven - works by "capitalising on the resources already present in the villages". The college, spread over eight acres, runs entirely on solar energy, maintained by the Barefoot solar engineers. Since the solar course was launched in 2005, more than 300 Barefoot engineers have brought power to more than 13,000 homes across India. A further 6,000 households, in more than 120 villages in 24 countries from Afghanistan to Uganda, have been powered on the same model. Only villages that are inaccessible, remote and non-electrified are considered for solar power. A drop in the ocean, perhaps - 44% of rural households in India have no electricity - but these women are making an important contribution to the nation's power needs.