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With much of the industry at this week’s WINDPOWER Expo in Dallas—including National Wind, check us out at booth #407—we thought this might be a good time to run down a variety of recent wind energy stories.

  • First up, a new study has been released by the National Renewable Energy Laboratory that adds to their 2008 study, 20% Wind by 2030. On the surface, this new study isn’t quite as sexy—it’s title, after all, is the Western Wind and Solar Integration Study—but it’s conclusions are just as promising.

    A bit of background: The WWSIS study was conducted to investigate the potential impact of a significant addition of wind and solar energy to the power system of West Connect, a series of affiliated utilities throughout Arizona, Colorado, Nevada, New Mexico, and Wyoming. Specifically, the study focused on the feasibility of the group generating 30% of its load from wind energy and 5% from solar. The study concluded that achieving such a high penetration is feasible and would require only a few key change to current practices. Chief among these changes would be creating better systems for aggregating renewable energy over large geographic areas—thus reducing overall variability—and scheduling energy disbursements at more frequent intervals.

    The study mentions a number of the benefits to the Western states should they implement West Connect’s plan. Most strikingly,”operating costs drop by $20 billion/yr, resulting in a 40% savings due to offset fuel and
    emissions.” While this drop in operating costs does not include the cost of constructing a wind farm, it illustrates how much money a wind farm can save over fossil fuels while operating.

  • In other news, “Ontario’s chief medical officer of health says there’s no evidence that the noise from wind turbines leads to adverse health effects.” While Dr. Arlene King offers that some people living near turbines may experience headaches or sleep disturbances, she concludes that wind turbine noise is not sufficient to cause hearing loss or other health effects. While this shouldn’t come as a surprise to regular readers, it’s always nice to receive validation from someone with Dr. King’s credentials.

  • Former President George W. Bush was the keynote speaker at this week’s WINDPOWER conference. He was apparently well received—”The audience welcomed Mr. Bush enthusiastically, giving him standing ovations at the beginning and end of his speech,” the article states—and spent much of the talk discussing signing Texas’ renewable portfolio standard in 1999 when he was governor, and about the country’s need to transition to renewable forms of energy. He said he’s enjoying retired life, living back on his ranch and being out of the limelight.

Well that about wraps it up. Keep your eye on AWEA Into the Wind blog for more updates on the WINDPOWER expo.

The processes at work behind harnessing wind and converting it into electric power are more complex than a quick surface glance might reveal. It isn’t simply placing a wind turbine in a windy area and letting the wind do its job, although that is the gist of it. Other factors are taken into account that dictate how fast and when the rotors of a turbine will spin so that wind is used as efficiently as possible.

One of the biggest recurring issues behind maximizing wind’s potential is working around one of the wind’s inherent qualities: namely, its intermittency. Since wind speeds fluctuate over the course of the day, researchers are investigating methods to help turbines generate a consistent flow of electricity that doesn’t vary as wildly as the wind speeds. A recent study from a team at Iran’s University of Science and Technology, for instance, takes a more detailed look at the “exergy” of wind power at various wind speeds. For those without a doctorate in thermodynamics, exergy is simply the available energy to do work within a system. By taking a more nuanced look at the wind potential at various wind speeds through improved exergy analysis, the Iranian researchers hope to better define a wind turbine’s cut-in, rated, and furling wind speeds, so that usable energy is maximized at any given wind speed. Based on exergy analyses at two Iranian wind sites, one in Tehran that experiences slower wind speeds and one in the windier town of Manjil, the Iran University of Science and Technology researchers formulated optimized values for wind turbine rotation speed, which can be altered depending on wind speed. Utilizing these values to manage rotation speed would theoretically yield a 20% increase in efficiency and an 80% recover of otherwise “wasted” energy.

Researchers at the University of Wisconsin – Milwaukee’s Department of Electrical Engineering and Computer Science are also working to improve wind turbines’ handling of intermittency. The Milwaukee researchers have taken a similar “exergistic” approach in addressing how to maximize a turbine’s energy output, in this case, using the inertia of the spinning rotor as an energy storage component. Using a braking control algorithm that adjusts the rotor speed, the rotor is allowed to speed up when incoming wind power is greater than average so that it can store the excess energy as kinetic energy rather than generating a surplus of electricity. This energy is released when wind power output falls below average, helping combat inefficiency by keeping the power produced steady and usable on the electric grid.

Of course, an updated and modernized transmission network would go even further in combating inefficiency and creating a more robust energy market. However, advances in technology that help turbines harness the variable wind energy in a more consistent fashion further show that the problem of intermittency isn’t insurmountable. We just haven’t been thinking “exergistically” enough.

Jon Wellinghoff, the chairman of the Federal Energy Regulatory Commission (FERC), made a bold statement on Earth Day, April 22, 2009, at the US Energy Association Forum. When questioned about new coal and nuclear generation, Wellinghoff responded, “we may not need any, ever.”

In making his assertion Chairman Wellinghoff argued that due to technological advancements in renewable and transmission, renewable energy is becoming increasingly cost-effective and progressively more competitive with conventional forms of energy. For instance, solar energy is now able to be stored for up to 15 hours, and regulatory commissions are allowing increasingly larger quantities of wind energy onto the grid. Given the current trends and assuming the implementation of a smart grid system, Wellinghoff said “ultimately wind’s going to be the cheapest thing to do,” so you’ll look to wind first to meet energy demand.

With a smart grid capable of shaping energy supply to meet demand (and vice versa), Wellinghoff said, the concept of baseload power will become an anachronism. “People talk about, ‘Oh, we need baseload.’ It’s like people saying we need more computing power, we need mainframes. We don’t need mainframes, we have distributed computing.”

Wellinghoff cited what many others have duly noted: there is enormous potential for wind development in the Midwest, but it can only be fully realized if we implement wind friendly policies and keep wind in mind when rebuilding our nation’s infrastructure.

It is certainly a boon to the wind industry for the chair of the Federal Energy Regulatory Commission to make such assertive statements, as the commission regulates the interstate transmission of electricity. Chairman Wellinghoff has an impressive track record behind him; he is an energy law specialist with more than 30 years of experience in the field and was the force behind Nevada’s Renewable Energy Standard, which was one of only two states to receive an “A” by the Union of Concerned Scientists for its design. His statements on the future of wind energy demonstrate the forward-thinking needed to stimulate growth and we are excited to see his vision become reality.

Wind energy is now, in regards to energy production, very competitive with conventional electricity sources. There are several fiscal concerns regarding dependability when considering wind turbines, including back-up generation, operation consistency, efficiency, and cost. However, these too, are very competitive with conventional power plants.

Because of the electric grid’s innate design, every megawatt of wind energy does not need to be backed up with a megawatt of fossil fuel. The Utility Wind Interest Group reported that “…even at moderate wind penetrations, the need for additional generation to compensate for wind variations is substantially less than one-for-one and is often closer to zero.” (2003) Furthermore, research conducted in 2004 for the Minnesota Department of Commerce determined that adding 1,500 MW to the system of Xcel Energy in Minnesota would need only an additional 8 MW of conventional generation to deal with the new variability. This addition would generate enough electricity from wind energy to power more than 400,000 homes!

Several sources of electricity considered extremely reliable, coal, nuclear power, or natural gas, for example, undergo unpredicted outages. They are also not backed-up with a comparable amount of generation from a different plant. Wind farms are built in windy areas where seasonal and daily wind patterns can be estimated. Because of this, wind is indeed a variable source of energy but it is not unreliable. How can we measure the productivity of a wind turbine or any other power production facility? It is done by comparing the plant’s actual production over a specific period of time with the amount of power the plan would have produced if it had run at full capacity for the same amount of time. It looks like this:

Capacity Factor =

Actual amount of power produced over time

Power that would have been produced if turbine
operated at maximum output 100% of the time

Wind turbines generate electricity most of the time (65-80%) but the output amount is variable. However, a power plant that operates at 100% of its maximum generation potential 100% of the time, doesn’t exist. Wind farms are built in locations where the wind blows at a constant rate, yet variations occur due to seasonal changes, so a wind farm will generate power at full rated capacity about 10% of the time. On average, a wind plant will generate at 30-40% of its rated capacity throughout the year. As more utility-scale wind energy projects are developed across the US, the number of wind turbines operating in a given area will increase. This has been shown to inherently reduce wind’s aggregate production variability, making it more predictable and reliable.

To date, a backup capacity for wind energy does not exist. Surplus wind energy can grow substantially during times that do not match customer use patterns. Therefore, there is a strong need to find ways we can store this “surplus” energy. Two proposed off-peak electricity uses of this “surplus” energy, include the deployment of plug-in hybrid vehicles with off peak charging and production of hydrogen to power vehicles.

Winds of change are a’ blowing. Everywhere you look Americans are rallying for renewable energy and green jobs. In a historic moment on January 23rd 2009, the EPA made a bold statement in favor of developing a clean energy economy by overturning the decision to permit a coal burning power plant, Big Stone II. Similarly, President Obama’s stimulus program proposes to double the amount of renewable energy on the power grid in the next three years. Every sign points to the fact that the US renewable energy market is on the verge of unprecedented growth. However, before this can happen, the American power grid desperately needs a makeover.

The current power grid is unprepared to deal with large quantities of renewable energy like wind and solar for two reasons. First of all, the areas that are most appropriate for wind and solar are often in sparsely populated areas. As a consequence of this, wind and solar energy often need to be transmitted across long distances. However, the current power grid does not have enough high voltage transfer lines to allow this to happen. As a result, wind developers today are often faced with one of two situations. Wind farms can be developed in less windy areas in order to take advantage of existing high voltage transfer lines to the detriment of wind power productivity. Or, wind farms can be developed at America’s windiest sites at the risk of losing large amounts of energy as electrons are lost in transfer across long stretches of lower voltage lines. Secondly, as wind and solar energy only produce energy when the wind is blowing or the sun is shining, it will be difficult to integrate large amounts into the grid until to the grid can better handle fluctuations in power. Without building an electrical grid that can accommodate fluctuations, the number of blackouts that the nation experiences would increase, while the reliability of the electrical system would decrease.

Luckily, however, investing in the power grid is a solution that works for everyone. It increases the efficiency and reliability of the grid while saving consumers money on their energy bills. According to a study conducted by the Joint Coordinated System Plan, if the power grid is updated to handle 20% of the East Coast’s electricity needs from wind, consumers could save as much as 12 billion dollars annually. An investment on this scale would be able to pay itself back in as few as 7 years, and would greatly reduce the amount of energy lost in transmission. If the power grid is extended to cover 20% of the entire country’s wind electricity, the cost for installing the system would be 80 billion. While this would be a substantial upfront investment, it would pay itself off relatively quickly, given the speed at which monetary savings could be recovered through greater efficiency.

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