Wind is a form of solar energy. The uneven heating of the atmosphere by the sun, the irregularities of the earth’s surface, and rotation of the earth cause winds. Wind flow patterns are modified by the earth’s terrain, bodies of water, and vegetation. Humankind uses this wind flow, or motion energy, for many purposes, to name a few: flying a kite/zeppelin, sailing, grinding grain, pumping water, and even generating electricity.
The terms wind energy or wind power describe the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power. This mechanical power can be used for specific tasks (such as grinding grain or pumping water) or a generator can convert this mechanical power into electricity.
A wind turbine works the opposite of a fan. Instead of using electricity to make wind, like a fan, wind turbines use wind to make electricity. The wind turns the blades, which spin a shaft, which connects to a generator and makes electricity. Large and modern wind turbines operate together in wind farms to produce electricity for utilities, while homeowners and remote villages, to help meet their energy needs, use small turbines.
Indonesia has relatively available potential site for wind energy utilization, but its utilization is still low. Currently, research and efforts are continuously conducted to open the possibilities of increasing the wind energy utilization.
Advantages/Disadvantages of Wind Energy
Despite its disadvantages, wind energy offers many advantages, which explains why it’s the fastest-growing energy source in the world. Research efforts are aimed at addressing the challenges to larger use of wind energy.
Because wind energy is fueled by the wind, a clean fuel source, it makes wind energy a clean energy. Wind energy does not pollute the air like common power plants that rely on combustion of fossil fuels, such as coal or natural gas. Wind turbines do not produce harmful emissions that cause acid rain or greenhouse gasses, so it is environmentally friendly.
Wind energy is a domestic source of energy, produced in the Indonesia . The nation’s wind supply is relatively available (especially in the eastern part).
Wind energy relies on the renewable power of the wind, which cannot be used up. As already mentioned, wind is actually a form of solar energy.
Nowadays, wind energy is one of the lowest-priced renewable energy technologies available. Depending upon the wind resource and project financing of the particular project, wind energy cost less than 6 cents USD per kilowatt-hour (for potential site with wind speed > 5 m/s or offshore).
Wind turbines can be constructed on farms or ranches, thus benefiting the economy in rural areas, where most of the best wind sites are found. Farmers and ranchers can continue to work the land because the wind turbines use only a fraction of the land. Wind power plant owners make rent payments to the farmer or rancher for the use of the land.
Wind power must compete with conventional generation sources on a cost basis. Depending on how energetic a wind site is, the wind farm may or may not be cost competitive. Even though the cost of wind power has decreased dramatically in the past 10 years, the technology requires a higher initial investment than fossil-fueled generators (and even other renewable based generators).
The major challenge to using wind as a source of power is that the wind is intermittent and it does not always blow when electricity is needed. Wind energy cannot be stored (unless batteries are used); and not all winds can be harnessed to meet the timing of electricity demands.
Suitable wind sites are often located in remote locations, far from cities where the electricity is needed.
Wind resource development may compete with other uses for the land and those alternative uses may be more highly valued than electricity generation.
Although wind power plants have relatively small impact on the environment compared to other conventional power plants, there is some concern over the noise produced by the rotor blades, aesthetic (visual) impacts, and sometimes birds have been killed by flying into the rotors. Most of these problems have been resolved or greatly reduced through technological development or by properly siting wind plants.
General Condition in Indonesia
Wind energy development is part of national energy program in order to realize a sustainable supply and utilization of energy.
There are some potential locations in the country for wind energy utilization.
Installed capacity for wind power is relatively still small compared to its potential.
Wind Energy Potential in Indonesia
Wind energy potential in Indonesia quite varies and could be classified into three categories, namely:
small-scale utilization, with wind speed of 2.5 – 4 m/s and capacity up to 10 kW;
medium-scale utilization, with wind speed of 4 – 5 m/s and capacity of 10 – 100 kW;
large-scale utilization, with wind speed and capacity higher than 5 m/s and 100 kW, respectively.
Recorded and measured wind data are as follow:
Region of Nusa Tenggara Barat: wind speed ranging from 3.4 – 5.3 m/s (10 locations);
Region of Nusa Tenggara Timur: wind speed ranging from 3.2 – 6.5 m/s (10 locations);
Region of Sulawesi and other: wind speed ranging from 2.6 – 4.9 m/s (10 locations).
Detail data* of each region is tabulated below.
* Data is properties of National Institute for Aeronautics and Space ( LAPAN).
National Wind Energy Technology
Generally speaking, US / Europe wind turbines available in the market are usually designed for high wind speed application which is not quite appropriate for wind condition in Indonesia . Meanwhile, there are some wind turbines, which might be appropriate to be used in the country. Therefore, development of wind energy technologies in Indonesia is widely opened. Currently, wind energy technologies developed in the country are designs and prototypes for:
power plants with capacity of 50 – 10,000 W;
mechanical power pumping with capacity of 45 – 250 liters/min;
power plants with capacity of 3.5 kW coupled with electrical pump for water pumping.
National Fabrication Capability
In general, status of national fabrication for wind energy conversion system is:
small-scale utilization: national industry has already able to built wind energy conversion system components up to 5 kW capacity and they are ready for mass production if the market available;
medium and large scale utilization: still under development.
Testing, information dissemination, and direct utilization of wind energy for various applications, to wit: lighting, battery charging, radio communication, television, radio, home industry, telecommunication, water pumping.
List of Companies Working on Wind Energy
Below are list of companies involved in wind energy development in Indonesia . To name a few:
PT Indonesia Power
PT Bumi Energi Equatorial
PT Guna Elektro
PT Indokomas Buana Perkasa
PT Citrakaton Dwitama.
To support wind energy development, the country already has various facilities:
wind potential measurement equipments;
wind energy conversion system laboratory;
aerodynamic laboratory – subsonic speed.
Below are several barriers encountered for wind energy development in the country, viz.:
technical and financial difficulties in data access for input on establishment of wind potential map;
limited fund to access and identify potential location especially in islands and remote areas;
relatively high price for wind energy compared to fossil based energy;
available wind energy products (usually for high speed application) are not suitable for the country’s application (low speed).