Taiwan's vertical-axis advantage
Moreover, since the key technologies for large wind power systems are controlled by American and European firms, Taiwan must import most of the components of such systems. But Taiwan can go it alone on small wind systems. We have a solid foundation in all the technologies related to its production, from the manufacture of composite blades to that of the electrical control systems and the bases. Taiwanese small wind is well positioned to grow and create its own niches. Given that these efforts are being supported by outstanding R&D teams, the future looks bright.
Take the small wind system developed by NTHU, which utilizes composite blades and a vertical-axis design.
Vertical-axis turbines differ from horizontal-axis systems in the direction of the axis of rotation of the turbine's blades.
Horizontal-axis systems are very loud. (The noise created by the blade tips is in direct relation to the fifth power of the speed at which the turbine rotates.) They also kill birds and won't spin unless they are facing into the wind. As a result, some 22 US states bar the installation of horizontal-axis small wind turbines in urban and residential areas.
Vertical-axis systems, on the other hand, are quiet, safe, easy to install, and turn no matter what the direction of the wind.
Crucial to a system's longevity is the material from which its blades are made.
Manufacturers in Taiwan and abroad used to use stainless steel or aluminum for the blades. But the blades, which had relatively small cross sections, corroded badly in three years of testing in the icy, sandy conditions of Inner Mongolia.
NTHU developed a turbine blade made from a polymer composite consisting of glass or carbon fibers and corrosion-resistant polyvinyl resin. The blades are safe and easy to install virtually anywhere, providing portable power whether sited atop a commercial highrise, in an amusement park, neighborhood or park, or on a farm or school campus.
Blades made from the composite material are only about one-fifth the weight of those made from older materials, and are more easily turned by the wind. Typical small wind systems need only light winds (3.4-5.4 meters per second) to generate power, but the NTHU vertical system works in as little as two meters per second.
Even more amazing is that the strength and design of the blades gives them a functional life of 15-17 years.
Small wind systems currently utilize recyclable lithium iron phosphate batteries to store power, but NTHU and Bei-jing's Tsing-hua University are now working together on the development of third- and fourth-generation environmentally friendly all-vanadium redox flow batteries.
Outlook for exports
Small wind has numerous strengths, but most of the systems presently manufactured in Taiwan are destined for export. According to the TSMWTA, Taiwan exported some 79% of the small wind systems it produced in 2010, with 64% going to mainland China.
Ma says that the mainland is making an aggressive move into wind and solar power and that wind turbines from around the world dot the broad Hoh-hot Plains of Inner Mongolia, hybrid wind-solar systems from Taiwan among them. Nowadays, the shepherds of Inner Mongolia don't ride horses, they ride electric motorcycles. They are also installing solar panels on the outside of their families' yurts. Nowadays, even convenience stores are selling solar systems.
Why don't we see small wind systems and solar panels on every rooftop in Hsin-chu? The main reason is that power in Taiwan is cheap and small wind systems aren't. There's simply no incentive for people to buy them.
NTHU vice president Yip Ming-chuen, the force behind the school's "low-carbon, green-energy campus" program, says it takes at least a decade to earn back a hybrid wind-solar streetlamp's nearly NT$200,000 cost through energy savings. Such high costs have prevented large-scale installation of the devices. As a result, the school has just six that it is using for research purposes.
NTHU and the Hsin-chu City Government have now created the "Small and Medium-sized Wind Power System Demonstration and Testing Platform" to promote the lamps. Under the program, a row of the hybrid street lamps will be set up along the shore of Qing-cao Lake and alongside the Taiwan Pavilion (relocated from the Shang-hai World Expo, and due to open in Hsin-chu at the end of the year).
But demonstration projects are only worth so much. If we hope to deploy the technology on campuses, in communities, and around ordinary homes, discounts are going to be crucial.
Right now, a 300 W small wind system costs NT$100-120,000. The kind of system necessary to provide the 3 kW a typical home uses or the 5 kW consumed by a farm runs NT$400-500,000. Consequently, there's just no incentive to buy small wind.
Going green
Will our built landscape someday incorporate small wind systems turning atop every home? Su argues that electricity is just too cheap right now. Most homes use less than 330 kWh per month at a cost of only NT$2.68 per kWh. Moreover, wind conditions vary greatly across the island, making it unlikely that small wind will be implemented islandwide. At the present time, its use is generally lim-ited to outdoor facilities and public spaces, such as streetlamps and fishponds, on farms and schools, and in parks.
Ma, on the other hand, is very positive on the market's outlook, arguing that prices will fall if production capacity grows. He forecasts that in three to five years the price of a 300 W system will fall below NT$100,000 and that of a 3 kW system will drop to NT$200-300,000. At those prices, buyers would earn back their costs in about 10 years. He believes that if we simplify the process for having Taipower purchase green energy from producers, rooftop power generation could have a very bright future in Taiwan.