Monday, November 11, 2013

Harnessing the Power of Wind – In Minnesota and Beyond


Several weeks ago on the way to Joshua Tree National Park from Los Angeles, I passed through the largest field of wind turbines I’d ever seen. And, as if on cue, strong gusty winds suddenly whipped through the San Gorgonio Pass, buffeting my lightweight rental car. I was inspired by the sight of wind turbines extending out to the horizon, and wondered what goes into decisions on where to build these icons of green energy.

Wind turbines in Southern California's San Gorgonio Pass. (Bill Stein)

Fortunately, I didn’t have to wait long. Just weeks later, Kate Mullin, resource modeling analyst from WindLogics, a St. Paul-based company that provides forecasting and optimization solutions for sustainable power, gave a most informative talk to the Twin Cities Meteorological Society. She talked about the process by which wind power developers estimate the future energy production of a wind farm. While the following is by no means a complete summary of Kate’s presentation, I thought I’d share some of the facts we learned that I found interesting.

There are highly detailed maps that depict wind across the United States, providing a basis for determining locations that may be best suited for the construction of wind turbines. These maps display average annual wind in meters per second. You can multiply meters per second by 2.2 to get an approximate miles-per-hour measurement.

Minnesota is just northeast of the nation's strongest average winds.

Although there are several small and isolated pockets of high winds in western parts of the country, the majority of larger-scale strong winds occur in the central part of the United States. Minnesota is among the windiest parts of the country with southwestern Minnesota – owing in part to the Buffalo Ridge formation – experiencing the strongest average winds.

Areas of southwestern Minnesota average winds of nearly 20 mph.

An analysis of potential sites for wind farms includes mesoscale weather forecast model data, such as the Weather Research & Forecasting Model (WRF), as well as terrain-based models that take a closer look at smaller geographic grids (1km and 50m resolution).

Meteorological towers (“met” towers) are used to capture hourly data such as wind speed, wind direction and temperature at heights of up to 100 meters. Wind flow models incorporate the data and produce forecasts of wind conditions for an extended period of time, such as 30 years. Ultimately, the data generated will determine if a project is financially viable during the pre-construction phase.

The actual design of a wind farm incorporates a variety of factors. First, it’s a function of where land can be obtained and if it’s subject to any land use restrictions. Additional considerations include the form of power transmission, whether the site is close to housing and development, and environmental restrictions.

(Kate noted that regulations for wind farms in Canada are particularly stringent given environmental and other concerns. In the United States, Iowa and Texas are among states considered the most “wind-friendly.”)

After the potential energy production from a wind farm is calculated, other factors that can cause production losses must be considered. One of these factors is wake, a concept we might think of when it comes to a cyclist drafting behind another cyclist in a velodrome or a car following closely behind a large truck on the highway. In wind circles, it refers to the effect that one turbine has on additional turbines that follow down the line. Kate shared a particularly interesting graphic depicting wake that most everyone in the wind industry has seen. It’s an image of the Horns Rev offshore wind farm in Europe’s North Sea.

Clouds form in the wake of the front row of wind turbines at the Horns Rev wind farm in the North Sea. (Aeolus)

Some of the other factors that can reduce the productivity of wind turbines include the availability of the proper turbine model (different models are built to maximize different wind environments) and curtailment, which occurs when wind conditions are favorable, but for one reason or another the wind energy is not sent to the power grid.

Weather can also cause wind turbines to become unproductive. For example, icing is a particular concern for wind turbines in our part of the country. And, interesting enough, there are some parts of the country where wind turbines must be turned off when bats are most active so they don’t get caught in them.

So the next time you see a wind turbine, whether in the California desert or on the snow-covered prairie in southwestern Minnesota, take pleasure in knowing that energy is being captured from resources that are continually replenished, but also know that a ton of work – including complex wind forecasts – go into the building of them.

Follow the Minnesota Forecaster on Twitter and Facebook.

18 comments:

  1. Interesting read Bill, I didn't know you were fascinated by the wind.
    As for todays weather if you blinked you missed it, the first snowflakes of fall/winter were mixed with the rain around 7am.....but to be honest I thought we would see more snow falling this morning after reading the last couple of NWS discussions, oh well enjoy the chill for the rest of the month because it looks to be below average temps the rest of the month.

    ReplyDelete
  2. Anyone catch Dave Dahl's blog tonight at KSTP.com, he is sounding the "heads-up" bell for early next week(Halloween week).....saying that right now it looks snowy and we might get our first significant snow of the season, he says to check back for changes which we all know will occur. My question to you all is is this a serious potential or just fantasy land on the models.

    ReplyDelete
    Replies
    1. @bigdaddy, Paul Douglas going with a "cold rain"early next week and warns of near freezing temps for Halloween(but no superstorms/blizzards).

      Delete
  3. Wow, reading this afternoons NWS discussion they paint the possibility of a pretty dynamic weather scenario setting up in the middle of the country next week and even reference the Halloween Blizzard characteristics that might occur with severe weather and winter weather. So does anyone have an opinion on what might occur in our neck of the woods with this possible storm.

    ReplyDelete
  4. Interesting catch @Big Daddy, though it does mention that things appear to be warmer than what occurred with the Halloween Blizzard.

    ReplyDelete
  5. There is a lot of disagreement among models right now pertaining to next week. GFS seems most favorable for snow-lovers right now, but ECMWF is somewhat favorable-

    The ECMWF- seems to develop the storm later, pushes the high to the north further south, brings in some snow (144hrs) but not much, and the High then collapses(180hrs). After, the low that has survives hovers near the gulf, and then rockets up to the north with the high now dissipated(216hrs). Very Halloween-blizzard-esque, but Wisconsin would receive the brunt of it.

    UKMET- similar to ECMWF, but keeps the high and strengthens it (144hrs). The model cuts off, but from prior experience, I am guessing it would batter the gulf and do nothing here.

    GFS- More of the “Get snow now” and not later. Gives us a very good shot of snow
    (132 hrs), and high pressure remains after and pushes low off to East before the low can come back up (174hrs).

    NAM- not in range yet

    JMA- High pressure stays north, so does snow, and for that matter, the rain.

    GEM- Spits the wave- first low overshoots us to the north, second one undershoots us and nails lacrosse

    ReplyDelete
  6. The weather centre has another good article for the upcoming winter...

    http://theweathercentre.blogspot.com/2013/10/final-2013-2014-winter-forecast.html

    ReplyDelete
  7. Of the many flights from ATL to MSP the view of the wind farms across Iowa and southern Minnesota is always impressive. To then get to drive through some of those around the Mason City area along I-35 was impressive. Wind turbine industry continues to push along requiring government investment/subsidies but really hoping it can grow in the free market and become very viable for energy and business. When storm chasing across the Plains there are several wind farms present including those along I-70 in central Kansas as they are perilously close to the interstate thus some great views of their size and magnitude.

    Great summary of Kate's talk as I know her and she is smart cookie!

    DD..

    ReplyDelete
    Replies
    1. DD, if you ever get the chance, take the drive along I-90 from Austin to Rochester, there is a large wind farm located about half way between the two.

      Delete
  8. This weather is boring, with a capital B. If we hung on everytime Dave Dahl mentioned snow since mid-October we should of seen at least six snow events already in the metro, he most definitely plays for ratings with his 'could' be's and 'potential' and 'probably' wording he uses when mentioning snow. Its obvious snow sells, just like sex sells, mention the word and it grabs peoples attention just like putting a pretty girl in front of a car in a car commercial or extra cleavage on the front of a magazine cover.

    ReplyDelete
    Replies
    1. Good thing Dave Dahl doesn't show cleavage. Then it'd be a double whammy, eh?

      Delete
  9. A major sever weather event ifs about to unfold to our southeast on Sunday 11/17. If you have friends or relatives in Eastern IA, Northern IL, including Chicago and extending north into Michigan and as far south as Kentucky and they here sirens please tell them to take the warnings very seriously as this could be a explosive event.

    ReplyDelete
  10. Everyone's non-favorite website....Accu-weather.....calling for a 80% chance of 3-6 inches of snow Thursday night.....true or false?

    ReplyDelete
    Replies
    1. @big daddy, there maybe some truth to Accuweather's forecast albeit on Friday(not Thursday night) but KSTP is saying "chance of snow with some accumulation possible".

      Delete
    2. @big daddy, there maybe some truth to Accuweather's forecast albeit on Friday(not Thursday night) but KSTP is saying "chance of snow with some accumulation possible".

      Delete
  11. Plymouth Weather LoverNovember 19, 2013 at 12:58 PM

    I would love there to be a new thread to talk about the snow coming for Thursday night! I know it may not be huge, but it is snow and it is cold enough so it may as well snow. Bring it!!!!

    ReplyDelete
  12. We use for our insurance business Portable Weather Measuring Instruments in our every Branch. We need to know about the weather and according to that select the installments and total amount that needs to be paid.

    ReplyDelete
  13. This comment has been removed by the author.

    ReplyDelete