How does Alltec Corporation stay at the forefront of hard-line business competition? We do this by continuously developing innovative solutions to our customers' changing needs. For this reason, Alltec has shifted one of its focuses to the renewable energy market, specifically wind power technologies. We know that height, shape and isolation are all leading factors in determining the place where lightning will choose to strike. Therefore, wind turbines being one of the tallest points, sustain a high probability of being struck by lightning. Consequently, it is often not a matter of "if" but "when" a wind turbine will be struck by lightning or experiences other types of overvoltages and currents.
Overall, wind energy technologies have a multitude of advantages, and they are clearly changing the way that society views alternative power sources. Wind power is a domestic source of energy (from within the US), which means we will remain independent from other countries while relying on wind technology. It is also a low price renewable energy technology, costing between only 4 and 6 cents power kilowatt-hour. Furthermore, wind energy saves the planet from harmful carbon emissions. Other ancillary benefits include: the lowering of natural gas costs, the creation of domestic manufacturing jobs for these projects, the generation of local revenues, and the reduction of water consumption.
However, even with these clear advantages, widespread misconceptions and criticisms about these renewable energy technologies still exist. Many people still believe that wind power is both costly and unreliable; they fail to realize that wind energy is actually becoming significantly less expensive and a better overall power quality option. In July of 2009, under the American Recovery and Reinvestment Act (ARRA), an estimated $3 billion in government funding was granted towards the development of renewable energy projects in the United States. While the millions of dollars of government subsidization will help with the financial startup costs of these wind energy projects, measures can be taken to dramatically improve the reliability and maintain the cost-efficiency of such a system. Properly installed lightning protection and surge suppression systems can help minimize costly equipment replacement and eliminate critical downtime.
As of 2008, the US currently ranked as the world leader in both wind energy generation and new wind energy capacity installation: it is now more important than ever to mitigate the chance of lightning strikes to wind farms. A properly installed lightning protection system will dramatically improve both the cost-effectiveness and reliability of a wind turbine. Without the system, a lightning strike on an unprotected blade can lead to temperature increases up to 54,000 degrees Fahrenheit and result in an explosive development of air within the blade. According to the updated National Fire Protection Association NFPA 780 handbook, "While physical blade damage is the most expensive and disruptive damage caused by lightning, by far the most common is damage to the control system." Wind turbines have a concentrated amount of very expensive technology installed in a relatively small space and many different voltages are present in a wind turbine installation, which can easily lead to overvoltages and surges within the system. Possible paths of lightning current to the wind turbine generator are as follows:
Strike to Tower
Strike to Nacelle
Strike to Blade
Strike to Power Line
Strike to Transmission Line
A strike to a tower or nacelle can induce voltages and current in the power cables and generator windings. A strike on a blade could lead currents to the generator through the blade and downstream equipment. Surges from lightning and switching on the power lines may also damage the generator. A properly installed lightning protection system intercepts the lightning bolt between the cloud and ground and effectively and safely conducts it to the earth without risking the complete physical destruction of the wind turbine and decreasing the likelihood of it catching on fire. A low-resistance, low-impedance grounding system is important for wind farms in that it links all turbines together forming a common ground grid.
Even without the possibility of being struck by lightning, wind turbines contain easily damaged sensitive electronic equipment; they contain motor-driven technologies using internal gear boxes or direct drives, as well as sensors to monitor wind directions. The internal switching and inductive loads within these applications make wind turbines particularly susceptible to power disruptions. Properly installed Surge Protection Devices (SPDs) act as an envelope and control power transients; they eliminate electronic confusion which is the leading cause of system downtime. Protecting wind energy systems from lightning damage and power quality issues is essential in maintaining the dependability and overall cost-efficiency of these highly sensitive power-driven systems.
The Department of Energy's "20% Wind Energy by 2030" report examined the realistic achievability of using wind energy to generate 20% of the nation's demand for electricity by 2030. With wind turbine projects accounting for nearly 42% of all new energy generation in the United States, it is becoming more probable that the United States will make that goal a reality. For this reason, it is now imperative for designers, contractors, owners and operators of wind turbine facilities to carefully consider lightning protection, grounding, and surge suppression technologies companies. Alltec Corporation has the knowledge, experience, reputation, and superior quality products to provide the optimal solution for your wind farm’s power quality, grounding, and lightning protection needs.