A good site assessment report from a certified assessor enables the installer to make an installation cost estimate without having to go to the site themselves, saving them a possibly long trip.

Interview with Amy Taivalkoski

Ed Blume | RENEW Wisconsin

Amy Taivalkoski
A good site assessment report from a certified assessor enables the installer to make an installation cost estimate without having to go to the site themselves, saving them a possibly long trip.
Interview with Amy Taivalkoski
Engineer and Wind Site Assessor
by Ed Blume, RENEW Wisconsin

Ask Amy Taivalkoski how she got to Wisconsin, and the story begins in Baghdad, where her father was a diplomat between 1972 and 1975, just as the recently deposed Saddam Hussein began making waves.

Because Baghdad offered no English high school, Amy T (as everyone calls her) attended boarding school in Massachusetts, but spent summers and vacations in Iraq and Egypt, her father's next posting.

Amy T always took an in interest in ecology and at 16 finagled her way into a solar energy conference in Cairo.

She earned a degree in electrical engineering from Brown University and then a Masters from Carnegie Mellon.

She migrated to California to work on the early engineering of optional character recognition (OCR) and then moved back to Massachusetts where she helped design robots to patrol warehouses or serve as TV news camera pedestals.

She had forgotten about renewable energy until she moved to Wisconsin with her husband, who landed a job as a land survey manager. Passing We Energies' Byron turbines one day, the twin towers triggered a memory of her earlier interests. She soon attended some free workshops on solar and wind energy funded by Focus on Energy. She then enrolled in all the wind energy courses offered by the Midwest Renewable Energy Association (www.the-mrea.org), eventually becoming a certified wind site assessor.

A list of wind and solar site assessors, including Amy T, is available at Focus on Energy www.focusonenergy.com or by phone at 1-800-762-7077.

What are the most common reactions when you do a site assessment for a potential turbine owner?

The most common misconception I encounter is that there is money to be made by installing a residential wind turbine to get free electricity and then sell the excess back to the utility. Clients usually experience sticker shock at the cost of a wind system, unless they've done a little research before they call me. Some people expect a payback in three or four years, which just will not happen because you are essentially paying for 20 years of electricity ahead of time.

A second misconception is that a short 50'-60' tower will do. They don't really think about the fact that to really generate electricity, you need to have clean consistent wind flow, and that means the turbine has to be way up above any trees or building. When I compute the minimum tower height, I always round up. Mick Sagrillo, who taught me much of what I know, says that the three most common installations mistakes are short tower, short tower, and short tower.

Some of the sites that I visit just don't make sense for a wind system, they could be surrounded by trees, in a low lying area, or just in a low wind resource area. The nice thing about a site assessment is that we are not selling anything. If you have a bad site, we will tell you.

Do you get any odd reactions to being a woman doing a site assessment? After all, we don't see many women electricians.

No. It's never been an issue, and it wasn't when I was in engineering classes or at any of my jobs. I always knew that I could hold my own so I never thought much about it.

What's a site assessment amount to? Walk through the process.

I get a call from someone who wants an assessment. They've gotten my name from a list of assessors maintained by Focus on Energy.

A lot of the assessment research is done on the computer. I can get aerial photos and topographical information for the specific site on the Internet. There's also wind resource data for areas around the state which can be analyzed to get a ball park estimate for the average annual wind speed at the client's site. Still, you always need to see the site for yourself. There may be trenching issues with the well or septic location; there may be electrical wiring issues; also you need to meet the client and get to know their interest in wind and the kind of needs that they have. I usually spend an hour with the client at their kitchen table getting to know all the details about their site and their electricity use. Then I explain wind systems to them, including some pictures of different turbine options, why towers need to be tall, what are the tower options, and the turbine energy outputs and costs. Usually you can also make some significant energy efficiency suggestions for them.

Meeting the clients is the most enjoyable part of the business for me. Everyone is different. I meet everyone from subdivision residents to farmers to entrepreneurs. I've done assessments at veal farms, dairy farms, hog farms, chicken farms, tree farms, hobby farms, and just normal homes.

Do you prepare a written report? If you do, what's the final document contain when you present it to the person?

Yes, I prepare a report, and it contains a lot, usually about 20 pages, and takes anywhere from 8 to 15 hours depending on the complexity of the installation.

I determine the minimum tower height, estimate the wind resource, including prevailing wind direction and the average annual wind speed at hub height (top of the tower). I'll add a wind rose graph to illustrate the percentage of time and energy in each direction sector that the wind blows on the site. I'll have picked out a couple of potential locations for the wind system during my site visit and 360 degree pictures from these sites are also included, along with the aerial photos and topo maps from the Internet. This report will be going to an installer and the installer needs to know all about the site before an estimate can be made.

The report also includes a description of the available types of towers (freestanding, guyed lattice, guyed tilt-up, and monopole) along with the advantages and disadvantages of each.

I'll list and describe their turbine options, anything from a 1kW Southwest Wind Whisper to a 35kW remanufactured V-15 for residential sites, depending on what is appropriate for their loads. Even larger wind systems are options for commercial sites.

Next comes output calculations for each turbine, based on the wind speed at the site, and I highlight the fact that the calculations only provide a ball park estimate. We certainly can't guarantee wind speed or output.

Site assessment chart prepared by wind assessor Amy T for a location in Waukesha County with an average wind speed of 10.7 mph at a hub height between 100' and 140'.

Finally, we get to system cost, including Focus on Energy incentives that might apply. Payback times are sometimes included if requested by the client. Usually the client can figure out the payback on their own if that is what they are interested in. I am certainly not an accountant. However, I can say that the cost of electricity will no doubt continue to rise, so the payback times will be decreasing.

Sounds like a lot of time and work to prepare a site assessment. How much does it cost?

There's no fixed rate. Each site assessor charges what they think is appropriate. Usually a residential assessment costs between $300-$400 with some additional charge for mileage, and a commercial assessment is $600-$700. Fortunately for the potential turbine owner, Focus on Energy offers a 75% discount coupon for residential clients, 50% for commercial, to cover a large part of the assessment cost.

I have traveled as far as La Crosse, Green Bay, and Door County to do site assessments. I started by saying I'd only travel 100 miles, but interest in wind is all over the state so I expanded my range.

Sorry, but I have to ask. Why pay you? Why not ask an installer to take a look and make recommendations?

That's certainly an option, but you have to remember that installers are in business to install. They would rather get a call from a client who knows he has a good site, and is ready to go, based on his site assessment report, than spend a lot of time and effort doing site assessments for people that either had bad sites or don't plan to install anytime soon. Also, a good site assessment report from a certified assessor enables the installer to make an installation cost estimate without having to go to the site themselves, saving them a possibly long trip. Plus, site assessors are not selling anything which allows the clients to have confidence that the report is unbiased.


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