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Thumbs up for just-in-time wind power

DTE Energy and contractor Barton Malow took an innovative approach to build the 112-MW Echo Wind Park in the Thumb Area of Michigan, using a just-in-time method that is well established in the state's auto industry.

By Paul MacDonald

When it came to building DTE Energy's latest wind power project in Michigan-the 112-MW Echo Wind Park-the utility borrowed a well-established practice from the state's auto industry and used just-in-time deliveries for the wind turbines.

Instead of placing the turbine components in a nearby laydown area and accessing them as needed, DTE Energy had GE, their turbine supplier, deliver the components directly to the project site in the Thumb Area of Michigan, north of Detroit.

"We had the deliveries sequenced so the turbine components pretty much went directly to the Echo Wind site," explained Matt Wagner, manager of wind development for Michigan-based DTE Energy.

"A truck carrying components would come in to Michigan and head right to the Thumb and to the site-it would go directly to the turbine foundation ready to receive the components.

"It was not always perfect," says Wagner. "There were times when we had a few turbine tower sections lined up on the road, and the same with blades. But generally, the just-in-time delivery system worked well."

Wagner noted that one of the attributes DTE Energy takes pride in is its focus on continuous improvement. "There is always room for improvement," he said. "But the just-in-time delivery was a good process, and I think there was a lot of savings in the schedule and costs because we weren't handling the wind turbine components more than we had to."

Like many utilities, DTE Energy-one of the country's largest power producers-is making a move toward renewable and alternative energy in its power portfolio. Last year, the company announced a deal with Ford to build Michigan's largest solar array-the second largest solar carport in the Midwest. The 1-MW project will be built at Ford's headquarters in Dearborn, Michigan. The project will come online in 2015.

With the commissioning of the Echo Wind Park last year, DTE's renewable energy portfolio now stands at 9.6 percent. The company is working to meet the state's renewable energy goals by generating nearly 1,000 MW, or 10 percent of its customers' electricity needs, from renewable sources. About 95 percent of that renewable power will come from wind.

The company has been involved with generating wind power for several years, both with its own wind power projects-including another project in the Thumb-and power purchase agreements with wind farms owned by other companies.

DTE's wind development involvement in Michigan's Thumb dates back to 2007, when they started acquiring land rights in the area.

"We understood that there was a Michigan Renewable Portfolio Standard coming, so in anticipation of that, we started looking and acquiring land rights in the area," said Wagner. "We knew that the Thumb, particularly Huron County right at the tip of the Thumb, had some very good wind resources-some of the best in Michigan." Adding to the fit, the Thumb was also in DTE's service territory.

"What we were doing was looking at which communities were ready for wind power and supportive of it and where the land resources made sense, in terms of it being very contiguous. The Echo Wind project is in an area that already had a couple of smaller wind farms, so a lot of things came together to set us up for a good project." In fact, about half of Michigan's wind turbines are now in the Thumb's wind-rich Huron County.

Looking at the Thumb on a map, you can see that it has Lake Huron on the east and Saginaw Bay to the west, both of which deliver good lake wind effects.

State regulations vary for power companies; in Michigan, DTE had to go to the Public Service Commission to present their contracts with the EPC, Barton Malow, and GE, turbine supplier for the Echo Wind Park.

"While there were a lot of ducks we had to have in a row for that, we came in with an organized application with sufficient detail for the PSC, and they were excited about the project," said Wagner.

The larger challenge came in dealing with the two townships on which the 16,000-acre project is located. Townships, like states, can have different approval processes-and that was the case with Huron County's Oliver and Chandler townships.

Chandler Township had more of an overlay approach, where a project is outlined for a general area and an approval results in a zoning change to allow for wind power. The design and project details are then scrutinized and approved at the planning commission level.

Oliver Township had a special use permit. Projects are proposed, site plans are provided, and a project is then reviewed and approved.

 
  

Generally, the difference between the two is that the overlay approach creates the opportunity for community engagement before detailed project design, whereas the special use permit approach seeks community input once a detailed project application has been submitted to community leaders, says Wagner.

The challenge came because the Echo Wind project-spanning both townships-had to follow both of those approaches for the turbines. So DTE was dealing with two different processes to get the project approved. "Fortunately, both of these communities were already hosting wind turbines, so it wasn't their first rodeo," Wagner said. After undergoing a rigorous review by both townships, the Echo Wind Park was eventually given the green light, and construction started in the fall of 2012.

"It's good to get your access roads in as soon as possible-the more certainty you have in terms of your operating surface, the more you can do beyond that," explained Wagner. "So we worked with the communities to put the access roads in, in the fall. That allowed us to go in, in the spring, even if the weather was a bit sloppy, and start working on the foundations because we could get into the fields where the turbines were planned."

Permitting drove some of the construction sequencing. If they were waiting for permitting in a certain area related to a stream crossing, for example, they would focus on another region.

"If we had permits for the south side of the project and were still waiting for permits on the north side, we'd sequence our road and turbine installs in that order," said Wagner.

As noted, the just-in-time delivery of turbine components worked very well.

Barton Malow, the EPC on the project, chose Tekla software to design the two types of wind turbine foundations for the project. Once Barton Malow's engineering team completed the design, the foundation rebar, concrete, and anchor bolts were modeled.

Each placing crew was given a drawing depicting their area with exact spacing and sequencing information, which was easily extracted from the Tekla model.

Because the models were so accurate, Barton Malow was able to take the dimensions from the model to show where each wind turbine would fit on the jobsite. The Tekla model showed any conflicts, which were corrected early on so that by the time they got to the construction phase, it was very organized and very well put together, says the company.

In addition to designing the foundations, Barton Malow put in roads to each wind turbine site, dug the foundations, placed the rebar, erected and set anchor bolt cages, formed the foundations, placed and finished the foundations, and erected the turbines-all on an extremely tight schedule. They poured two foundations each day to meet the schedule.

After the first foundation went in, Barton Malow got positive feedback from the field. After that, it was just a matter of duplicating the process. Taking the time to model the concrete and rebar detail in Tekla really paid off on the backend to meet their installation schedule, says Barton Malow.

In addition to the good wind the area possesses, the other advantage of the Echo Wind site is that it is mostly agricultural-and flat. "Where you have a lot of farmland, you have a lot of flat terrain so the wind is less restricted; that's a recipe for a decent wind resource," says Wagner.

Being near water brings good wind, but it also brings some environmental considerations.

"We knew when we started doing wind energy in the Thumb that there were some extensive habitats and species that we had to be aware of and concerned about," explained Wagner. "One thing we've focused on is wildlife issues, particularly birds and bats."

Nearly three years prior to planning its first wind project in the region, DTE carried out extensive wildlife studies across Huron County and surrounding areas. Whenever they do a project in the region, they can draw on that database and, additionally, carry out a specific site assessment for wildlife agencies, such as the U.S. Fish and Wildlife and Michigan Department of Natural Resources.

"We will typically do two iterations with Fish and Wildlife," says Wagner. "We will do a preliminary layout and then drive them out to the site. Based on their feedback, we see what we can do. As an example, we had some turbines at Echo Wind that were close, from an eagle standpoint, to one river, and we re-sited them.

 
DTE Energy had GE, their turbine supplier, deliver components directly to the Echo Wind project site in the Thumb Area of Michigan. Trucks carrying components would come right to the site and go directly to the turbine foundation ready to receive the components.  
  

"Fish and Wildlife doesn't regulate us, but we work to accommodate them. In fact, I don't think there is a single case where they have asked us to consider a turbine move and we haven't done it. DTE values environmental stewardship, and this is consistent with that."

A challenge that many utilities and development companies find when they are building wind projects on agricultural land is that the farmers, understandably, care a great deal about what is going on with their land.

"The land is the livelihood of the farmers in these communities," says Wagner. "We made a decision very early on that we were going to respect our hosts-essentially, we are guests on their land.

"We do everything we can to minimize the impact of our projects on their land, which basically means, for example, if we can put a turbine on a property line between two landowners so that we don't impact their tillable fields as much, we are going to do that.

"The landowners are good caring people, and they put a lot of stock in their land, and it is incumbent on us to maintain trust with them as we do what we need to do."

In the case of Echo Wind, newsletters were issued, and there were weekly or bi-weekly meetings with landowners during the project's construction. "We try to be visible during all project phases-development, construction, and into operation."

DTE Energy's relationship with the landowners and local people is different with Echo Wind in that they are not just the project's developer and owner-they are their utility. "We have been there for 100 years, and we want to go the extra mile and be a good neighbor," says Wagner.

While farmers are as tech-savvy as everyone else in terms of the Internet-looking up commodity prices online and getting the latest crop reports-they prefer plain old direct communication when it comes to talking through issues. "A lot of the farmers want to work face-to-face, rather than sending an email or a letter," says Wagner. "It's not unusual to reach an agreement on some construction challenge with a conversation and a handshake."

Wagner said it was important that Barton Malow, as EPC, shared DTE Energy's approach to keeping the community in the loop and being sensitive to local issues. "They recognized with us that we are guests on the land-it's valuable to have a partner that is aligned with you in terms of your philosophy with the landowners, and with DTE's approach to safety, which is a big priority. And Barton Malow did a good job on all those fronts."

Barton Malow is Michigan-based, as was their electrical subcontractor, MJ Electric. Wherever possible, DTE Energy and its contractors sourced materials locally and within Michigan.

All major construction projects have their challenges, and Echo Wind was not different in that respect. A hurdle appeared in Novem-ber 2013: DTE suspended commissioning activities after the project experienced a blade failure on a turbine during an initial turbine start-up reliability test by GE.

No injuries occurred as a result of the failure. Root-cause analysis of the blade failure resulted in the replacement of 15 of the 210 blades at Echo Wind.

"We worked with GE over several months and brought in an independent consultant to provide their expertise," said Ed Henderson, DTE manager, Renewable Energy Development. The blades were replaced, GE provided extended warranties, and Henderson says DTE Energy was satisfied with how GE handled the matter.

With the Echo Wind project now behind them, DTE has moved on to planning the company's next wind project, a 100-MW wind farm, which will also be in Huron County. This size of project provides DTE Energy with some benefits of scale, both in terms of construction and operations. "We've found a certain amount of comfort with projects of about 100 MWs, though we've also done smaller projects," says Wagner. There are some economies of scale, he said. "But the biggest story is that when we acquired our first wind project, it was $110 per MWhour, and now we're doing projects or purchasing projects below $50 per MWhour.

"That is not necessarily an economies-of-scale thing as much as it is technology improvements and just the way DTE-and the wind energy industry at large-are figuring out how to do projects better and how to optimize capturing the wind and generate power from that wind."

It's clear going forward that, for DTE Energy, it is thumbs up for wind energy.

 


May/June 2015