Reused bike parts and a pressure cooker have been combined to create a wave energy harvester powerful enough to charge a mobile phone.
Nottingham Trent University undergraduate Owen Griffiths (above right) and professor Amin Al-Habaibeh came up with the invention, and a working prototype is displayed at the university’s degree show.
wave phone charger
Griffiths said: “A small-scale product like this, partly made from reused goods which are widely available, could help provide power to coastal areas which otherwise may not have a wide access to electrical energy.”
A pressure cooker, which by design is air-tight and floats on water, is used as a buoy to bob up and down with the waves.
A rack fixed to the pressure cooker lid creates linear energy as each wave passes beneath. Lengths of bicycle chain are used as teeth for the rack, while two sprockets convert the linear energy to rotational energy.
As the rack moves upwards with a wave, the first sprocket turns and powers the generator while the second is disengaged, as when a cyclist freewheels.
The rack moves down as the wave passes, so the second sprocket turns and the first is disengaged.
This allows the harvester to maximise its efficiency by generating power from both the rise and fall of each wave.