Traditional power plants that burn coal and natural gas are unsustainable. Fraught with issues such as pollution caused by mountaintop removal and strip mining to maintain coal reserves, and fracking to access natural gas, they are on their way out in many places. As the Fukushima Daiichi tragedy in Japan, the Chernobyl disaster, and several smaller-scale accidents have proven, nuclear power is clearly not as safe as originally believed; it, too is being scaled back in many places. Clean, sustainable energy alternatives have been in the works for some time now; one of the most intriguing is the use of offshore wind farms to harness the power of ocean breezes. Interested? Let’s take a closer look.
Why We Need Green Energy
Before we look at this amazing energy source, let’s take a moment for a quick reality check. The electricity many of us rely on is generated using dirty methods that cause pollution and harm our planet. Not only does pollution happen onsite and in areas where coal and other fossil fuels are removed from the earth, it runs downstream, ending up in our rivers, lakes, and oceans; ultimately, this pollution has caused fish die-offs and other ecological disasters that we, as a society, have become fairly numb to. Doesn’t it make sense to work toward using renewable energy everywhere?
Wind Turbines: Clean and Sustainable
Wind turbines are simple mechanisms based on technology that has been around for millennia; people have been using wind energy since about 3,000 BCE when Egyptians used it to power sailboats. Windmills, traditionally used for applications such as pumping water for drainage and irrigation, and for milling grain since about 2,000 BCE, have been used to generate electricity since Professor James Blyth of Scotland created one of the first prototypes more than 100 years ago, in 1887. By the 1930’s farmers were using windmills to generate electricity in areas of Australia, Canada, the United States, and other nations, but as energy corporations set infrastructure in place, interest in wind generated energy waned since coal was plentiful and cheap. Fortunately, this interest never died out; and in the 1970’s and 1980’s, the alternative energy movement once again gained momentum as fossil fuels became more costly.
The principle behind turbines is very simple – a series of blades capture the wind, capturing kinetic energy in the same way energy from flowing water is captured by turbines inside a hydroelectric dam, while the shaft connected to the blades rotates, generating energy which then exits via protected power lines, entering the grid for distribution to consumers. While early wind turbines dating back to about the mid-1980’s had an average power rating of about 150 kilowatts per hour, the newest turbines are rated for up to approximately 4 megawatts per hour, per turbine. To put this in perspective, the average US household uses a little less than 12 megawatts per year, meaning that a single high-tech turbine can generate enough energy to run an entire household in the space of about three operational hours.
A little more math: It takes about 500 tons of coal to produce 1,000 megawatts; that’s approximately half a ton of coal per megawatt. If your annual energy consumption is 12 megawatts, then you use around six tons of coal per year just to enjoy the convenience electricity combines.
It gets worse. Not all the energy produced by burning coal for electricity actually goes into the grid for distribution. Some of it ends up as byproducts. Each ton of coal burned produces around 2.685 tons of the greenhouse gas carbon dioxide, thanks to the principles of atomic weight and chemical reaction. Additional byproducts include Nitrogen Oxide, which is a component of acid rain and smog, as well as Sulfur Dioxide, which is a major acid rain component. Combine these byproducts with the most common methods for mining coal, which are environmentally unsound, and we have a recipe for environmental disaster.
Wind, on the other hand, is a natural phenomenon, plus, there is an endless supply. The amount of energy we can capture using turbines is limited only by the number of wind turbines we can erect and by their capacity to convert wind to usable electricity. On land, wind farms are relegated primarily to ridge tops and open plains where wind blows at a fairly steady rate, and people who wish to live off the grid now have the option to purchase and install their own miniature wind turbines for power production. With real estate at a premium though, the viability of wind energy has been seen as somewhat limited. In 1991, new possibilities became reality when Denmark installed the first offshore wind farm and was met with immediate success.
Other nations followed suit, quickly recognizing that this form of electrical generation ought to go from being an alternative to becoming a vital part of mainstream energy production. As of 2011, there were 49 working offshore wind farms in nine European countries, with more being constructed. While some turbines in deeper water are mounted on floating bases in the same manner buoys and floating solar panels are, those in shallower water are mounted on fixed bases.
In Canada, offshore wind farms are in the works, with a major project underway off the West Coast of British Columbia. In the United States, plans for development off the East Coast are underway, and both countries have plans to set up offshore wind farms in the Great Lakes. Interest is growing in other nations too; notably, in Japan, China, and India, where offshore wind energy is abundant.
A Bonus for Marine Life and Divers
Both wave energy devices, which harness the ocean’s energy and transform it to usable electricity, and offshore wind farms create habitat for marine life – that’s right – they form artificial reefs. Heaps of rocks piled around the bases to prevent erosion promote growth, and new designs that utilize different textures and shapes are being used to encourage artificial reef formation as well. Wind farms generally take up several square kilometers, and while they do generate a small amount of noise along with the electricity that they produce, neither it nor the motion of the turbines seems to scare the many crabs, lobsters, and bottom dwelling fish that have taken up residence in the existing artificial reef environments they have created.
Sharing what you know about renewable energy is an excellent way to make a difference. If each of us adds our voice, we might soon see some reversal in the harm caused by current pollution causing power production methods – and, we might be able to dive our power plants; a fantastic bonus to look forward to.