Hydroelectric generator targets developing countries

Students at Cambridge University have developed a portable hydroelectric generator that could be used to power homes in developing countries.

The FloDrive Turbine, displayed at last month’s Cambridge Manufacturing Engineering Design Show, can produce up to 1kW of power when deployed in free-flowing rivers.

The third-year students, Deniz Erkan, Li Jiang and Ned Stuart-Smith, aimed to design a generator that was easy to install without training and needed no special infrastructure or equipment.

The 500kg device is designed for small-scale use on flowing rivers rather than dam-controlled waterways, but multiple devices could be deployed along a single river.

‘Current water technology mainly exploits the flow energy either in the form of tidal energy or potential energy created manually by big dams or naturally in mountainous area,’ Jiang told The Engineer.

‘However, a large proportion of rivers are constantly flowing in slow flow rate. Therefore, the FloDrive Turbine was designed for river with a minimum flow rate of 1m/s and a uniform flow rate profile.’

One of the key issues for the students was designing the device to adapt to different river sizes, which was tackled by creating an on-land supporting system that allows easy installation and maintenance.

The team also developed a brushless generator to increase the device’s robustness and lifetime. These have previously been used in wind turbines but not hydroelectric systems; however, improving technology has reduced their cost to an economic level for small turbines.

The students received several offers from university consultants and people wanting to buy the FloDrive at the show, but the team estimates that the device would need another year’s work to turn it into a commercial product.

Development has halted as the students are working on other projects, but Erkan said the FloDrive could be used under a similar model to Imperial College London’s Equinox – a non-profit project providing solar generators to rural villages in Rwanda.

‘We wanted to design something targeted at developing countries that could be used as a reliable charger for things like charging mobile phones,’ said Erkan. ‘The advantage of water power is that it could provide electricity 24 hours a day, unlike solar or wind.’