Chile's Wind Energy Advantage: The Roaring Forties and Furious Fifties

Last week I reviewed Chile’s energy demands and discussed the types of sustainable energy being produced in Chile. While hydroelectric plants are integral contributers to their overall power supply, there has been much interest in exploring other viable sources of energy. Over the past ten years, the Chilean government has diversified its risk of blackouts from droughts by investing in thermal energy plants. These plants generate electricity by burning fossil fuels – coal and natural gas, which are decidedly not renewable. With the world realizing that we cannot depend on a non-sustainable source of energy, governments have started to funnel investment into finding new, cleaner ways of meeting their electricity demands. Similar to the past Chilean energy diversification into thermal electric generation, a consortium of government and private entities have been exploring the benefits of wind and solar energy. While clean technology has certainly been a buzzword lately, Chile provides us with one of the most interesting case studies because of the specific geographic competitive advantages that the country has. In this article, we will focus on harnessing the power of wind through those advantages.

Wind is actually a form of solar energy. The sun’s radiation heats the air and causes it to rise. As the air cools and falls, it creates a circulation of the atmosphere that we call wind. A wind-electric turbine generator (or “wind turbine,” as it is usually called) is used to convert the energy from these streams of air into a usable, highly-productive form called electricity. I’m not going to spend too much time discussing the specific technologies or parts that make up a wind turbine, but the generator functions similarly to a hydroelectric plant. An invisible current or stream of wind passes through the rotors (blades of the fan) of the turbine, causing it to spin. This motion converts the wind into rotational shaft energy, which (through the rest of the turbine system) is then converted into electricity. Typically, for large-scale electricity generation, a “farm” will be built that is composed of dozens of turbines.

So now the biggest questions are: What are the most important factors for understanding the potential electricity that can be produced? Where should we build our wind farms?  First, the energy that is contained in the wind is a function of the cube of the wind speed. For example, a 12 mph wind holds 70% more energy than a 10 mph wind. Second, the wind must be consistent. Undoubtedly there will be a variation in the speed and frequency of the wind, but areas that have intermittent wind are not prime locations. Third, the Earth’s geography and the concentrations of solar radiation on any one area contribute to these overall circulation patterns of the atmosphere. Thus, there are specific places where wind energy is higher or lower, since the speed is higher or lower. Which place is Chile?

Because Chile is so long (it covers about 4300 km from top to bottom), the country is quite geographically and meteorologically diverse. In the north is the Atacama desert, one of the hottest places on Earth. The closer to the middle of the country is home to Santiago and a nice Mediterranean climate. And I haven’t seen it with my own eyes, but the lakes region in the south is supposed to be one of the most beautiful places on Earth. But what’s also in the south are two sections of land called the Roaring Forties and the Furious Fifties. These areas were given their names by sailors from the 1800 and 1900’s whose unfortunate task it was to travel around the tip of South America. The latitudes between 40 – 50 and 50 – 60 maintain some of the highest speed and most consistent winds on Earth. Since the energy contained in wind is the function of the cube of its speed, these latitudinal areas establish Chile as the categorically best location on Earth to build and operate sustainable wind energy farms.

Make sure to check back next week, when we’ll be discussing solar power in Chile.