Renewable energy: Blowing in the wind (Fourth of a Series)

By Henrylito D. Tacio
There are non-renewable energy sources and there are renewable energy sources.
Non-renewable energy depends primarily on fossil fuels which include coal, oil, and natural gas. Renewable energy source, which are considered to be inexhaustible, includes solar power, hydroelectric, geothermal energy, and biomass energy. 
Climate change, population growth, and fossil fuel depletion mean that renewables will need to play a bigger role in the future than they do today. Of those renewable energy sources mentioned above, which is more advantageous to be tapped?  If you ask American singer Bob Dylan, he would reply: “The answer my friend is blowin’ in the wind…”
And yes, he is right!  “Across the developing world, countries are beginning to see the way the wind is blowing,” said Klaus Toepfer, former executive director of United Nations Environment Programme.  “Once it was believed that only one percent of their area was suitable for wind power.”
Not anymore.  “The serious development of wind power in modern times began in 1973 after the oil crisis shook the confidence of the developed world that oil was there for the asking.  Today, wind power is the fastest growing energy source in several regions of Europe, with the United States and India following behind in total installed capacity. And the potential is enormous,” notes Dr. Leon Freris, a visiting professor of renewable energy at the Centre for Renewable Energy Systems Technology in Loughborough University in England.
In Denmark, for instance, wind energy now contributes 13 per cent of national energy consumption, the highest proportion of any country in the world. When the wind blows strongly, wind energy supplies more than half the electricity in the western half of the country.
Lester Brown, of the Washington-based Earth Policy Institute, said more than 70 countries are now developing wind resources.  “Between 2000 and 2010, world wind electric generating capacity increased at a frenetic pace from 17,000 megawatts to nearly 200,000 megawatts,” he wrote in “Harnessing Wind, Solar, and Geothermal Energy,” a chapter which appeared in the book, “World on the Edge: How to Prevent Environmental and Economic Collapse.”
The Philippines, home to more than 7,000 islands, is following suit.  In fact, wind power now makes up a small percentage of the total energy output of the country. Two of the largest developments are the Bangui Wind Farm in Bangui in Ilocos Norte and the Wind Energy Power System (WEPS) in Puerto Galera in Mindoro Oriental.
The Bangui Wind Farm, the very first large-scale wind power plant in the country, cost 50 million dollars to build.  The windmills were built by Northwind Power Development Corporation, a private firm headed by a Danish engineer.  It became operational in June 2005.
According to Northwind, the wind farm supplies up to 40 per cent of the electricity requirement of Ilocos Norte. It also sells the supply to the Ilocos Norte Electric Cooperative at a discounted rate.
“Power supply is more reliable nowadays and that’s because of the windmills,” Elinao Ramiento, a barangay councillor in Taguiporo, one of the barangays being energized by the 25-megawatt wind power plant, told journalist Girlie Linao Mar.
Ramiento recalled that when a typhoon cut off power supply to the barangay one time, it didn’t take long for the service to return after the deluge.  “The windmills apparently made it easier to get power back to us,” he surmised.
As for WEPS (which will generate once completed an estimated 48 MW, thus making it the largest in the country generating power from the wind), President Benigno Aquino III signed in 2012 the proposed Luzon Mindoro-Interconnection project, which would allow for excess electricity to be transported to the nearby island of Luzon. “Before I end my term in 2016, I want to see Mindoro exporting its surplus power to Luzon,” the president said during the signing ceremony.
According to the World Wildlife Fund, there are more than 1,000 wind sites in the northern and central Philippines, with a potential capacity of at least 7,400 megawatts – enough to power 19 million homes.
Today, people are realizing that wind power “is one of the most promising new energy sources” that can serve as an alternative to fossil fuel-generated electricity.  Wind power is the conversion of wind energy into a useful form of energy, such as using wind turbines to make electrical power, windmills for mechanical power, wind pumps for water pumping or drainage, or sails to propel ships.
Actually, societies have taken advantage of wind power for thousands of years. The first known use was in 5000 BC when people used sails to navigate the Nile River. Persians had already been using windmills for 400 years by 900 AD in order to pump water and grind grain. Windmills may have even been developed in China before 1 AD, but the earliest written documentation comes from 1219. Cretans were using “literally hundreds of sail-rotor windmills (to) pump water for crops and livestock.”
The Dutch were responsible for many refinements of the windmill, primarily for pumping excess water off land that was flooded. The windmill was further refined in the late 19th century in the United States; some designs from that period are still in use today. The first large windmill to produce electricity was the “American multi-blade design,” built in 1888. Its 12-kilowatt capabilities were later superseded by modern 70-100 kilowatt wind turbines.
“Wind turbines for electricity generation are essentially simple devices, though their design requires deep understanding of the properties of wind, aerodynamics as well as mechanical and electrical engineering,” explains Dr. Freris.
The kinetic energy in the wind is intercepted by three or two rotating, slender blades. The action of these blades is to extract energy from the wind by slowing it down. This extracted energy first appears as mechanical energy on the turbine shaft and then as electrical energy from a generator coupled to the shaft through a gearbox.
“The power in the wind is proportional to the cube of the wind speed, hence doubling of the wind speed results in an eight-fold increase in electrical power generated,” informs. Dr. Freris.  “Wind turbines are designed to stop if the wind speed becomes excessive and do not rotate if the wind speed is too low for useful energy extraction.”
Wind turbines are usually congregated in wind farms, consisting of few or as many as 100 machines. By installing several machines on a site the costs of connection to the electricity grid and the operation and maintenance costs are reduced.
Aside from wind power being environment-friendly, it is also cheaper.  “If a household used wind power for 25 percent of its needs, it would spend only $4 or $5 dollars per month for it and the price is still dropping,” contends alterenergy.org. “Compare this to 4.8 to 5.5 cents per kilowatt per hour (kWh) for coal or 11.1 to 14.5 cents per kWh for nuclear power.”
Wind power has its shares of drawbacks.  Modern wind turbines rated at around 1 to 2 MW are large structures. Typically, a rotor of 60 meter diameter is attached to a nacelle at the top of a 60 meter tall tubular tower. Not surprisingly their environmental impact has not pleased everyone.
Controversy over their appearance is fuelled by the fact that wind farms are usually installed on tops of hills which make them prominent. In the past, wind turbines were also rather noisy. However, recent research has resulted in much quieter machines therefore noise is now not a major environmental issue.
Compared to the environmental impact of traditional energy sources, the environmental impact of wind power is relatively minor in terms of pollution. Wind power consumes no fuel, and emits no air pollution, unlike fossil fuel power sources. The energy consumed to manufacture and transport the materials used to build a wind power plant is equal to the new energy produced by the plant within a few months. While a wind farm may cover a large area of land, many land uses such as agriculture are compatible, with only small areas of turbine foundations and infrastructure made unavailable for use.
There are some concerns about bird fatalities on wind farms. A study in the Altamont Pass Wind Resource Area in California found 182 dead birds, 119 of which were raptors. In response to this, the wind industry is committed to modifying the equipment in order to make the area safer for birds.
Of course, wind power should not be the only source of electricity.  Generally, hydroelectricity complements wind power very well. When the wind is blowing strongly, nearby hydroelectric plants can temporarily hold back their water, and when the wind drops they can rapidly increase production again giving a very even power supply.
The answer is not only blowing in the wind but the future is based on it.  As singer Peter Frampton wrote: “The future’s in the air, I can feel it everywhere; blowing with the wind of change…” (Conclusion: Power from the sun)