A clean energy called wind
Among the many concerns of sustainable development and possible solutions to the present day crisis, renewable energy is among the critical. Justifiably so, for if we burn out the limited stocks of coal, gas, timber and such sources, our civilization would perish for lack of energy resources. As such, much work has been focused towards sourcing energy from alternate sources such as geothermal, bioplants, ocean tidal, hydro electricity, solar, and wind. Not all of them can be produced in the context of a building, where presently solar water heating leads the list. Next to it, much has been discussed about generating power from the wind, with the generator located atop or by the side of the building.
While experts feel power from the wind has unlimited potential, they equally feel we cannot tap it all. The technology required to harness the power is simple, but often it can get so costly that the savings may get wiped out. As such, it needs careful evaluation before installation.
Wind is always in motion due to surface temperature variations, day and nights, oceanic conditions and many such factors, simultaneously producing kinetic energy. This energy can be converted into electricity by letting the wind rotate a fan of blades which rotates a shaft where the shaft is connected to the wheels of a generator. Power thus produced can be connected to a transmission system in case of large-scale generation; or in small-scale operations, stored in a battery for later usage. Considering the fact that wind speed varies, leading to intermittent supply, wind energy for buildings is always coupled with solar and main grid, called hybrid power system. Periodic replacement of batteries creates waste and demands expenses, but the supply to grid option is yet to be finalised for small-scale units.
The major components of the system are tower to support the rotor blades, rotor to turn the turbine, gear box to control speed, charge controller and regulators to divert excess load to dump load and save battery, fuses and resisters to regulate electricity flow, battery to hold power, inverter to convert DC to AC power, brakes to control blade rotation and, finally, outlet sockets. Though this sounds complex, most of these can be fabricated in any small town. In case of small-scale building level units, they are better done locally rather supplied by branded units from far off places, to keep the costs low and quick referrals for maintenance.
Wind power has evoked much interest in India, yet it lies largely untapped. Without energy by wind, the Egyptian ships would not have sailed and civilization evolved; the Romans, Cholas and Vikings would not have had victories overseas and the medieval explorations across the high seas would not have connected the world before phones and planes did. May be, wind power now holds the key to another chapter of the future world.