WIND TECHNOLOGY
Wind turbines are used to produce energy by capturing the kinetic energy present in wind. A wind turbine has three main parts: the turbine (which consists of rotor blades and the rotor), the shaft and the generator. The rotor blade acts as a barrier to the wind and movement of wind causes this blade to move in a circular motion. The rotor blade is attached to a shaft, which then turns a generator that produces electricity.
Reference: Government of Ontario
The size of wind turbines varies widely. Small turbines can be used to power homes or businesses. These small turbines are usually rated at less than 100 kilowatts. Larger commercial turbines are often grouped together into wind farms that provide power to the electrical grid. These large installations are sized to produce hundreds of megawatts of renewable energy. Very small turbines that typically produce 20 to 500 watts of power charge batteries for recreational purposes such as boating.
There are two types of wind turbines: horizontal axis and vertical axis.
Reference: Government of Ontario
Horizontal axis is the most common type of wind turbine. The blades of the turbine are located perpendicular to the ground, with the axis (rotating point) located parallel to the ground. The efficiency of the turbine is highest when it is pointed directly into the wind. Tail vines are a common way to achieve this alignment.
Vertical axis wind turbines have blades that go from top to bottom and rotate around a vertical axis. The most common type is the Darrieus turbine. The major benefit to installing a vertical axis turbine is that it is always aligned with the wind. The main drawback is that it is less efficient than the traditional horizontal access type.
Oy Windside Production Ltd. of Finland manufactures a range of wind turbines specifically for use in extreme environments. They have been a supplier to Antarctic research groups for over 10 years and have 25 years manufacturing experience for turbines that are used in extreme conditions. These turbines are used to charge battery banks that in turn power equipment and systems. Their application is suitable in locations where solar may not be effective due to snow loading or high winds. These turbines are designed to withstand winds of 60 m/s or 216 km/h.
Wind turbines require annual maintenance to ensure that all parts are functioning properly. Maintenance activities include: oiling/greasing of moving parts, checking bolts and electrical connections, monitoring for corrosion and wear on blades, and ensuring that the tower is properly secure. Approximately every 10 years, the rotor blades and bearings will need to be replaced. With routine maintenance, wind turbines typically have a lifespan of 20 to 30 years.
The potential drawbacks to installing wind turbines include: affecting wildlife (commonly birds, bats), noise (from turbine rotation), annual maintenance requirements, and impact on the natural landscape (visual and spatial). Many technical issues (such as noise) have been addressed as the technology of wind turbines has improved. Also, bird and bat populations are now studied in detail at sites where wind turbines are installed for commercial or industrial use. Example topics of study include determination of species present, typical migration routes, daily activities and potential to impact habitat.
Trends
Popular areas of research today in the wind energy field include: optimization of rotor blades to increase the aerodynamics of the turbine, decreasing losses in mechanical components of the system, lowering noise produced, and making turbines more cost-effective.
Precedent
Wind turbines are being installed to power eight research stations in Antarctica. They will replace diesel generators. Wind speeds in the Antarctic reach up to 200 mph making wind turbines an ideal way to produce power in this isolated place. The Proven 6 Turbine has been successfully installed and operated in the Antarctic and is an effective and emission-free choice for this location.
Reference: Proven
Challenges associated with installing turbines in harsh climates include: build up of ice and rime on the turbine, damage to rotor blades, metal fatigue due to exposure to extended periods of low temperature, and structural problems due to high wind speeds.
Southwest Windpower has recently developed a new turbine called the Skystream. It is the first residential, grid-tie turbine that can be effectively situated in a backyard. The Skystream (rated capacity 1.9kW) generates 30 to 80% of the total electricity required by an average house depending on the wind availability and results in huge energy savings to the user. The newly designed rotor blades are curved to increase efficiency and decrease noise.
Reference: Southwest Windpower