Superior air power

A tethered wind turbine floating up to 300m (1,000ft) above the ground could provide cheaper electricity by picking up the stronger winds that are found at higher altitudes, according to its Canadian developers.

Each Magenn Air Rota System (MARS) device is filled with helium and functions like a spinning airship floating many times higher than a conventional wind turbine. According to

chief executive Mac Brown, the system could provide emergency power for areas hit by natural disasters.

Aerodynamic fins along each device catch the wind to power two generators that are fixed to each end of the device. Although Brown concedes that MARS will not be as intrinsically efficient as conventional fixed wind turbines he believes the system carries a number of benefits that make it a viable alternative.

'Traditional wind turbines can never run 100 per cent of the time because of the lack of wind, so they tend to operate at 26-42 per cent efficiency,' said Brown.