Is wind energy the future?

Timon Singh

Is wind energy blowing away the competition? It would appear so, as this alternative energy source is currently the fastest developing renewable power in the US.

The science behind wind power is simple; as there is wind, there will be an energy source. As such, countries have put their wind turbines in areas where stronger and more consistent winds are known to be, such as high altitude sites and near the oceans. While the turbine farms we currently have work efficiently, the only criticism of wind power is that in order to fully provide sources of energy to the world, there would have to be wind turbines everywhere and critics fear we do not have enough land for that.

In the US, however investment in the wind sector is continuing to grow. Last year wind power in the United States had reached about 35,000MW of installed capacity (enough to power 9.7 million homes), with the country surpassing Germany as the world's largest producer of wind generated power. The US now even has the world's largest wind farm in the shape of the Roscoe Wind Farm in Texas.

However a larger one is planned...

Future wind projects

In December, energy giant GE announced that it had been awarded the $1.4 billion contract to supply wind turbines and provide services for an 845MW wind farm project in Oregon, which will become the largest ever constructed, exceeding the power production of Roscoe.

The project will cover 30 square miles in north-central Oregon, near the town of Arlington, with the project marking the US debut and largest single global order of GE's 2.5xl wind turbines. A total of 338 turbines will be installed in 2011 and 2012.

The $2 billion project is expected to rake in $16 million annually for the state of Oregon, employing 400 workers during its construction and 35 during operation. The project's construction stretches far beyond wind turbines, with 85 miles of road and 90 miles of power connection to the grid also being built. Under three 20-year power purchase agreements, the wind farm will supply renewable energy to Southern California Edison, an Edison International company.

The project will help California meet both its capacity needs and renewable energy goals, with the capacity to generate two billion kilowatt-hours per year of renewable energy - enough to power 235,000 average Californian households - the wind farm will represent more than one-tenth of Southern California Edison's overall renewable energy portfolio.

However despite such seeming benefits, wind farms have been causing problems.

Running interference

In the state of New York, wind farms have attracted negative attention by causing Doppler radar interference. The farms upstate are interfering significantly with National Weather Service Doppler radars, making it increasingly difficult to accurately predict developing weather systems - approaching lake effect snow storms in particular.

The large turbines' spinning blades reflect some of the radar's signal, which can subsequently be falsely interpreted as strong winds or precipitation. But, as well as making the storms that come off lakes Erie and Ontario look stronger than they actually are, the turbines can also hide approaching storms from forecasters.

But, more worryingly, turbines have led to false tornado alerts in western regions. Even though the issue is seen as more of an inconvenience than a serious problem, it does highlight the fact that along with all their benefits, renewable energy sources do not come without their problems. Take wind farms for example, as well as wind being totally free and zero-carbon-emitting, strong wind is intermittent which means power generation is inconsistent.

However, scientists are hoping to change that with 'super wind turbines'.

The future of wind turbines

Traditionally, the three blade system on a wind turbine means that more wind power passes around its blades than through its motor. Their rigid structure therefore prevents turbines from capturing the super-strong winds that blow thousands of feet in the air. Some experts insist the total energy within these winds is 100 times the amount needed by everyone of the planet.

So how does one go about harnessing this power? Some research groups have developed advances on the humble kite to try and harness wind's immense power, but there is another way.

Selsam, the self proclaimed alternative energy innovator, have developed a "flying wind turbine" that is capable of stretching beyond the reach of the traditional turbines and turning these high winds into high voltage. These "Superturbines" are also far more efficient that the old-fashioned windmill as it eliminates all components that do not directly contribute to power generation, resulting in a low-cost wind turbine.

The Selsam Superturbine is equipped with multiple, synchronous, small rotors and with a universal joint that enables it to tilt - but not rotate - like a reed bending in the wind. Selsam's prototypes produce 6000 watts in 32.5 mph winds - six times more power than a similarly sized seven foot single-rotor turbine can produce. The turbines can be easily deployed by land and by sea, and their effectiveness can be amplified even further via an air-born blimp.

The Selsam SuperTurbine

The company website describes the turbines as so: "Like a flock of geese, each rotor favorably affects the next in line. Like a set of louvres, the tilted rotors pull in fresh wind from above, deflecting their wakes downward to insure fresh wind for succeeding rotors and, like a stack of kites, to add overall lift which helps support the drive-shaft against gravity and downwind thrust forces."

"The rotors act as gyroscopes or spinning tops, stabilizing the drive-shaft where they are attached."

Since the turbines rotate at higher rpms than traditional turbines, a small and light direct-drive generator can be used instead of a hulking gearbox.

The traditional wind turbine industry is reaching a tipping point as companies, such as energy giant GE, admitting they unable to make turbines fast enough to meet demand. No surprise when you consider the huge manufacturing process involved. However, the stripped down Superturbine is more efficient, and cheaper and easier to produce than than large lumbering windmills, and also extremely versatile.

While we have yet to see whether the Selsam Turbine has a future, it is clear the wind energy will be around for a long time to come.

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