Saturday, September 3, 2011
Taking the fleece to the mill and touring the research sites
Photo: Unity College anemometer tower site in Dexter, Maine.
I took a nice long field trip yesterday.
The primary spur for the field trip was the recent tropical storm, Irene, which necessitated site visits to all my wind anemometer towers to check guy lines and make sure the towers were still safe. The towers are measuring the wind to help determine where Maine's wind power systems should and shouldn't be located. I'm responsible to the state and the landowners for the safety of the towers.
If I was going to visit the sites, then I'd have to pull the data too. It's always good to pull data when you can, and make multiple copies of the data files, in case something goes wrong with the equipment later.
This is enormously valuable data -- there have been five billion dollars of internal investment already in Maine's wind power industry, as well as many millions of dollars and years of labor spent in compensation, litigation, and out-of-court settlements for noise nuisance created by wind farms, and our survey, a joint project with the University of Maine School of Engineering Technology, is the one of very few systematic programs in the state that show much promise to reduce some of these costs. It's the only program that is working with hard wind data. The state needs these data very badly. It's my job to secure it.
If I was going to drive around the three sites where we have stand-alone anemometer towers (there are three other sites where we have sensors placed on buildings or cell towers), then I might as well drop off the fleece from the Womerlippi Farm sheep at the woolen mill, which is on the way, and pick up my store credit slip in return. Our small and very unprofitable farm needs all the income it can get.
The first site, the W. R. Sherburne and Sons dairy farm in Dexter, Maine, is one of the state's largest and most successful organic dairy farms. This is a very successful and vigorous enterprise, and it just happens to be located on top of a hill, the northern side of which the Department of Energy's 50 meter wind map says is a Wind Power Density Class (WPC) 2 resource area. Class 2 is not adequate for any kind of commercial turbine, but there is good scientific reason to think that the map is inaccurate, particularly when it comes to northern exposures, and there is good scientific evidence to suggest that the winds at higher elevations, at the 60-100 meter range of modern turbines, are greater than Class 2.
We've already demonstrated that the wind power density class of a site not far from this one is WPC 4, when the map says that it's WPC 2.
I was able to pull the truck right up to the tower. I examined the guy lines, then pulled the data chip and copied the file to my computer.
Here's the computer logger, an NRG Symphonie. This is a state-of-the-art device that can log two years of data from over a dozen different kinds of weather sensors without requiring so much as a battery change. (Although in practice, I tend to check the batteries quarterly along with the towers -- you may as well do so.)
The next stop on my field trip was the Bartlett Yarns woolen mill in Harmony, Maine. Earlier, I had loaded about 150 pounds of fleece in black contractor bags in the back of my truck.
The Bartlett Yarns mill makes high quality woolen yarns and other woolen products, materials for hand spinners such as roving, as well as woolen clothing and bags and such. The yarn is cleaned, carded and spun on site using the original nineteenth century equipment.
A hundred or a hundred and fifty years ago, Maine was packed with small scale industrial enterprises like this one. Maine also had a lot more sheep then. In fact, in my home town of Jackson, Maine and the neighboring town of Dixmont, sheep husbandry was the primary agricultural system.
Here's the mill building and the Womerlippi Farm truck offloading the fleece.
Other than selling directly to the customer, which requires patience and marketing skills I don't have, small scale wool producers have two options for selling their fleece in Maine. You can sell to the annual Maine Sheep Breeder's Association Wool Pool for ¢50/pound. Or you can get store credit at Bartlett Yarns.
Store credit allows you to purchase Bartlett Yarns products -- carded and washed wool, roving, and yarn -- at a price less than wholesale. Our price works out to roughly $3.50 a skein. We can sell the yarn on in small quantities at $7/skein, and could probably do better yet online, so the wool business is at least potentially a source of farm income.
Up to this point the Womerlippi Farm management (just Aimee and I!) has not, however, made much money selling yarn. We're working on it slowly, in much the same way we're working on making money on eggs, livestock, and meat products. Every year we make one or two improvements to the system and close the gap between costs and income a little bit more.
Bartlett Yarns itself is a wondrous place, like stepping back in time, but it's also a profitable business selling a premium product at what seems to me to be a very affordable price. Look online and you can quickly find similar yarn for sale for twice, or three times the price. It's not unheard of for hand knitters to pay $20/skein for hand-dyed yarn. Bartlett Yarn's product is not hand-dyed, but it costs much less. Four or five or six skeins make a decent sized woolly sweater, and you might pay $30 for that much yarn at this venerable and very useful business.
Have I mentioned I like woolen sweaters? I keep trying to figure out how to make them on my own knitting machine with our own yarn. I haven't made one I like yet, but I'm having fun trying.
Here's some of the Victorian machinery at Bartlett Yarns, and some of their quite beautiful product.
I use slideshows of machinery like this whenever I talk about the Industrial Revolution in class.
Back in the day, a lot of child labor would have been used, but in this day and age, there's no exploitation at the woolen mill, just a team of ordinary Mainers trying to make a decent product, a decent living, and to make sense out of one of our otherwise under-utilized and even wasted agricultural resources.
From Harmony I drove west to Mercer, Maine, where another anemometer tower resides atop a hill that is home to one of Maine's most successful sheep farms. Blue Ribbon Farm in Mercer produces premium breed stock and high quality commercial hay.
A good long and somewhat overdue chat with the owner was the first order of business. The results from the first year of data collection at this site raised more questions than answers because of a very high, almost suspect wind shear factor number. The wind shear is the term in the Power Law equation that corrects for increased wind at higher elevation above ground level. You derive the wind shear factor empirically by having a lower and a higher anemometer on your anemometer tower, and reversing the Power Law equation to derive the wind shear as the unknown. You may then more accurately correct for wind speeds at different elevations. The higher the wind shear, the higher the wind speed above the topmost anemometer on your tower, and the lower the wind speed below the topmost anemometer.
The measured wind shear at this sites, and at a lot of our sites in Maine, is very high, much higher than expected. Until DoE and NREL came out with a paper earlier this year that suggests similar results for the midwest, I was unable to explain these results. I'm still at a loss, but am beginning to know what to do. The first thing I need to do is get more data from my high wind shear sites, which means I'd like to leave my tower on this particular hayfield for another year. The landowners have to give up some hay to make this possible, so this required me to explain myself properly as to why we needed to do this, and what potential benefits and pitfalls might ensue.
Here's the tower the day it was finished last year, with the wind crew members Amanda and Steve that helped me put it up.
And that, other than the drive back to college and an hour or so of less pleasant paperwork, was my big day out last week, the first week of term.
One idea that occurs to me, now I've finished this blog post, is that the folks at Bartlett Yarns, the Womerlippi Farmers, the dairy farmers at Dexter and the sheep farmers at Mercer hosting our anemometer towers all have something in common -- we're all trying to make economic sense out of good farming and good husbandry and rural, small-scale renewable energy in Maine.
That doesn't make us necessarily better people, but it does mean that we are at least trying to be more self-reliant, and at least trying to figure out a way to live within the planet's means.
One very under utilized resource is the educational uses to which field work like this can be put in helping students learn to live within the planet's means.
One of the things I like about my life is that I get the chance to combine my work as an educator and researcher with my hobby and second job as a small farmer. Students enjoy coming to the farm and learning about sustainable husbandry, and I enjoy teaching them. We have a series of such field trips scheduled, and I'm looking forward to them. I also enjoy having students work on the various research and demonstration projects I have ongoing at any given time, and using the lessons that arise, spontaneously or planned, to more effectively deliver lessons.
Unfortunately, because of the college schedule, it's hard to get the much longer periods of time that would be needed to take students through some of the more interesting processes and to more interesting sites. This is one of the factors behind my perennial complaint about the so called fifty-minute college class -- an oxymoron if ever there was one, that a routinely unsuccessful pedagogy prevents our use of a routinely successful one. Regular readers will be familiar with this particular meme so I won't repeat it. But yesterday was a case in point. A superb field trip in agriculture and renewable energy went to waste for lack of students.
Where were the students? In fifty minute classes, carefully distributed throughout their day in such a way as to prevent their participation in an all-day field trip.
I can, however, post the details of the expedition here, with photographs, and that will have to suffice for now until the college figures out a way for me to get students into these experiences more easily. I'm working on various ideas, such as summer programming and block scheduling.