WIND

In recent years, wind energy has become one of the most economical renewable energy technologies. Today, electricity generating wind turbines employ proven and tested technology, and provide a secure and sustainable energy supply. At good, windy sites, wind energy can already successfully compete with conventional energy production. Many countries have considerable wind resources, which are still untapped.

A technology which offers remarkable advantages is not used to its full potential:

Ø Wind power plants can make a significant contribution to the regional electricity supply and to power supply diversification.

Ø A very short lead time for planning and construction is required as compared to conventional power projects.

Ø Wind energy projects are flexible with regard to an increasing energy demand - single turbines can easily be added to an existing park.

Ø Finally, wind energy projects can make use of local resources in terms of labour, capital and materials.

The technological development of recent years, bringing more efficient and more reliable wind turbines, is making wind power more cost-effective. In general, the specific energy costs per annual kWh decrease with the size of the turbine notwithstanding existing supply difficulties.

Many African countries expect to see electricity demand expand rapidly in coming decades. At the same time, finite natural resources are becoming depleted, and the environmental impacts of energy use and energy conversion have been generally accepted as a threat to our natural habitat. Indeed these have become major issues for international policy.

Many developing countries and emerging economies have substantial unexploited wind energy potential. In many locations, generating electricity from wind energy offers a cost-effective alternative to thermal power stations. It has a lower impact on the environment and climate, reduces dependence on fossil fuel imports and increases security of energy supply.^[

For many years now, developing countries and emerging economies have been faced with the challenge of meeting additional energy needs for their social and economic development with obsolete energy supply structures. Overcoming supply bottlenecks through the use of fossil fuels in the form of coal, oil and gas increases dependency on volatile markets and eats into valuable foreign currency reserves. At the same time there is growing pressure on emerging newly industrialized countries in particular to make a contribution to combating climate change and limit their pollutant emissions.

In the scenario of alternatives, more and more developing countries and emerging economies are placing their faith in greater use of renewable energy and are formulating specific expansion targets for a ‘green energy mix’. Wind power, after having been tested for years in industrialized countries and achieving market maturity, has a prominent role to play here. In many locations excellent wind conditions promise inexpensive power generation when compared with costly imported energy sources such as diesel. Despite political will and considerable potential, however, market development in these countries has been relatively slow to take off. There is a shortage of qualified personnel to establish the foundations for the exploitation of wind energy and to develop projects on their own initiative. The absence of reliable data on wind potential combined with unattractive energy policy framework conditions deters experienced international investors, who instead focus their attention on the expanding markets in Western countries.

It is only in recent years that appreciable development of the market potential in developing countries and emerging economies has taken place. The share of global wind generating capacity accounted for by Africa, Asia and Latin America reached about 20% at the end of 2008, with an installed capacity of 26 GW. This is attributable above all to breathtaking growth in India and China: these two countries alone are responsible for 22 GW. This proves that economic use of wind energy in developing countries and emerging economies is possible, and also indicates that there is immense potential that is still unexploited.

The Technology

Wind power is the conversion of wind energy into electricity or mechanical energy using wind turbines. The power in the wind is extracted by allowing it to blow past moving blades that exert torque on a rotor. The amount of power transferred is dependent on the rotor size and the wind speed.

Wind turbines range from small four hundred watt generators for residential use to several megawatt machines for wind farms and offshore. The small ones have direct drive generators, direct current output, aeroelastic blades, lifetime bearings and use a vane to point into the wind; while the larger ones generally have geared power trains, alternating current output, flaps and are actively pointed into the wind.

Direct drive generators and aeroelastic blades for large wind turbines are being researched and direct current generators are sometimes used.

Since wind speed is not constant, the annual energy production of a wind converter is dependent on the capacity factor. A well sited wind generator will have a capacity factor of about 35%. This compares to typical capacity factors of 90% for nuclear plants, 70% for coal plants, and 30% for thermal plants.

As a general rule, wind generators are practical where the average wind speed is 4.5 m/s or greater. Usually sites are pre-selected on the basis of a wind atlas, and validated with on site wind measurements.

Wind energy is plentiful, renewable, widely distributed, clean, and reduces greenhouse gas emissions if used to replace fossil-fuel-derived electricity. The intermittency of wind does not create problems when using wind power at low to moderate penetration levels

PCRET Work

Pakistan Council of Renewable Energy Technology (PCRET) has successfully completed installation of wind turbines under a PSDP Project "Electrification of Remote Coastal Villages is using Wind Energy" by installing 155 micro wind generators, electrifying more than 1600 houses. Under the Project 0.5, 1.0, 3.2, 5.0 6.0 and 10 K.W wind turbines were imported from China, USA, Spain, Germany and Australia. They have been installed in the coastal belt of Arabian sea in the provinces of Sindh and Balochistan. PCRET technical personal has acquired training in assembling and installation of these wind generators through the courtesy of Peoples Republic of China. These wind turbines are functioning successfully and supervisory service, in case of operation and maintenance is provided to the end-users by the PCRET technical staff.

Presently, PCRET intends to acquire expertise in design and fabrication of different components of wind turbines in the range of 5kw and 10kw power generation capacities. Technology transfer for this purpose is required to be made from leading countries in wind energy technology i.e. China, USA and others.

There are hundreds of villages in the coastal belt on the Arabian Sea that need to be electrified by wind energy as they are not included in the priority program of the Government for rural electrification due to difficult terrain, Whereas viability of the wind power generation has already been established by installing 155 small wind turbines in the area. It can be adjudged from the fact that a large number of applications are pending with PCRET for installation of wind turbines.

The energy derived from wind power over the globe till December 2008 exceed 100,000 MW, which represents 40% of the total energy derived from other sources of Renewable Energy (Hydro, Solar, Biomass Geo –Thermal etc.) all over the world.

The coastal belt in Pakistan has power generation potential of more than 50,000 MW that can be harnessed through appropriate wind machine for which local manufacturing of wind turbines is necessary in order to save precious foreign exchange.

Feasibility study on the availability of wind velocity at sustainable speed for running wind turbine in the coastal belt of Arabian Sea located in the Provinces of Balochistan and Sindh of Pakistan has been carried out. It has been found that the wind corridor is available from Gharo to Keti Bandar in Thatta district of the Sindh Province, having a power generation potential of 50,000 MW. Similar is the case of Lasbella District of Balochistan Province, where wind at a sustainable speed, good for power generation is available with little variation in the seasons (5 meters per second in winter and 8 meters per second in the summer).

Ø 155 wind-generating units of 0.5 kw to 10 kw power generation capacity have been installed for the neglected segment of the society.

Ø About 1600 houses of remote coastal villages in Sindh & Balochistan have been electrified.

Ø More than 400 applications for wind electrification from remote coastal village, are pending with the PCRET due to successful completion of first phase of the project.

Ø There is a need for further dissemination of technology, as most of the villages in the coastal areas, particularly, in Lasbela district of Balochistan, Badin and Thatta district in Sindh are still deprived of the basic amenities of life including electricity.

The following measures need to the adopted for better and smooth functioning of wind turbines.

Ø Selection of sites must be need based and on available potential (wind speed) interest, cooperative aptitude of beneficiary and will.

Ø Wind Turbine (stand alone system) are to be provided to those villages, which are physically inaccessible and economically feasible for supplying electricity from the national grid.

Ø Projects on “Wind Energy” for meeting the country’s energy needs should be encouraged particularly for electrification of remote coastal villages.

Ø Local manufacture of wind turbines should be encouraged for economic exploitation of the wind energy potential available in the country.

Ø Government should facilitate the local manufacturers of wind turbines by exempting taxes on import of raw material like permanent magnet, copper wire, polymers etc. required for local manufacturer of wind turbines.