Micro Wind Turbines
Micro (or personal) wind turbines are sprouting on the rooftops of many UK homes in an effort to defeat our addiction to fossil fuels and reduce greenhouse gas emissions. Laudable goals, but most of these 'off-the-shelf' roof-mounted wind turbines struggle to generate enough electricity to power a single light bulb.
Using wind energy as a power source is hardly new, given the extensive use of windmills prior to the Industrial Revolution. Then, as now, these machines needed to be exposed to wind. In high density housing, typical of UK cities, personal wind turbines tend to be either hidden by obstacles (e.g., chimneys) from their vital wind energy source or a victim of slow-moving, turbulent air. To achieve maximum efficiency, the turbine rotor needs to be aligned perpendicular to the wind direction – adding another layer of complexity to the device and its mountings.
Currently, the most cost-effective means of capturing wind energy uses clusters of huge horizontal-axis wind turbines on land or at sea in windy areas. But even these highly optimized machines are typically only capable of generating power intermittently. Neither micro wind turbines nor wind farms are a total solution for our power needs.
But fear not, we do have a secret weapon that might address the shortcomings of micro wind turbines – human ingenuity. Inspired by nature and spurred on by competition, hobbyists, lone inventors and small companies are a force comparable to evolution with a dash of revolution. The process can be messy and inefficient, but then, as if by chance, out pops the 'obvious solution'. It happened during the evolution of the computer into the personal computer (PC), and the same forces (huge interest and demand) are gathering again for micro wind turbines. To get started, take a good look at the variety of horizontal- and vertical-axis wind turbines. Maybe there's inspiration waiting in the past?