By Justin Martino, J.D., associate editor
The Ohio River, the main tributary of the Mississippi River, is 981 miles long and flows through six states. Its average depth is about 15 feet, raised to accommodate navigation from a natural depth varying from three to 20 feet by a series of 20 dams operated by the U.S. Corps of Engineers.
The river is also a major source of untapped hydropower, and American Municipal Power (AMP) is in the process of using four of the dams on the river as a baseload resource for its 129 members in seven states. The four projects – located at the Cannelton, Smithland, Willow Island and Meldahl dams – will add more than 300 MW of generating capacity to AMP’s members’ portfolios without adding emissions.
Diversifying the portfolio
The decision to make a $1.5 billion investment in hydropower started from a decision faced by many companies in the power generation industry – AMP was looking to diversify its generation portfolio in order to cut down costs for its members.
“The industry started changing,” AMP Vice President of Communications Kent Carson said. “Power supply is the principal focus of the organization, and we help our members secure long term power supply contracts – basically market purchases. With changes in the industry, it became harder and harder, if not impossible, to get those long terms contracted at fixed costs. Our members were overly exposed on the wholesale market, which can be and at times has been very volatile.”
The organization embarked on an effort to develop projects that would allow members to fix the cost of some of the power by owning the generation asset, and a major component of that became creating new hydropower assets.
The organization developed and currently manages the Belleville Hydroelectric Facility, a 42 MW run-of-the-river hydropower plant at the Belleville Locks and Dams. The facility went online in April 1999.
“We knew the Ohio River was a relatively untapped resource,” Carson said. “The dams on the Ohio River were built in the ’50s and ’60s. They were built and are operated by the Army Corps of Engineers, and their principal function is navigation, to maintain the pool levels for the barge traffic that goes up and down the river, but they have the potential to add hydroelectric powerhouses and generate electricity.”
AMP contacted MWH Global, which served as the owner’s engineer for the Belleville Hydroelectric Facility project, and asked the company to do a screening study of the existing locks and dams on the river that did not have power. MWH performed the study in 2006, ranking the potential sites from most developable to least developable.
From there, AMP began the process of securing the development licenses for the best sites for power generation projects.
|The four powerhouses being built by AMP on the Ohio River will add more than 300 MW of renewable generation capacity to the organization’s members’ portfolios.|
Although the projects might be new, AMP was not the first organization to look at the possibility of putting hydroelectric powerhouses on the dams. That created a few problems.
“A lot of these projects have been looked at numerous times over the past decades, and in some cases people had pulled FERC licenses to develop them but just never got the capital together to actually move the project forward,” said Paul Blaszczyk, vice president and project manager with MWH.
Where there were no existing licenses, MWH helped AMP with obtaining them, including approvals and permits from both the U.S. Army Corps of Engineers and FERC. Because of the nature of the projects and the lack of recent new hydropower builds, one of the approvals – to modify a federal facility – had never been done for a hydroelectric power facility before.
“When AMP started the process, these four jobs were the first four hydro projects that had to go through that approval process,” Blaszczyk said. “While the approval process was defined and known for things like adding features to a levee on a riverbank and things like that, nobody had ever done it for a hydro facility. That was a bit of a challenge and a bit of a learning curve because we would ask the regulatory folks, ‘What do you need?’ and they would come back and say, ‘We’re not quite sure.’ We ended up getting through it, and AMP kind of set the mark here moving forward when you’re developing at Corps facilities relative to that process. But that was a bit of a challenge up front on the regulatory side.”
The licenses and Meldahl were acquired by the township of Hamilton, Ohio.
Building on the four dams
All four of the projects will use turbines and generators from Voith Hydro, based in York, Pennsylvania. The projects will use identical controls, which will assist if operators need to travel from plant to plant. There are many differences between the four projects, however.
“What we’re not able to do is take a cookie cutter approach,” Carson said. “The projects are similar in that they’re run of the river and horizontal bulb turbines, but that’s the end of their similarities. Each one of the projects is unique and became its own project with its own challenges and advantages.”
The Cannelton Project, located at the Cannelton Locks and Dam, will use three 29.3-MW bulb-type turbines. The facility’s total rated capacity is 88 MW, and it will generate an average gross annual output of approximately 458 million kilowatt-hours.
The Smithland Project will divert water from the Smithland Locks and Dams. It will use three 25.3-MW bulb-type turbines, creating an estimated total rated capacity of 72 MW with a gross annual output of around 379 million kWh.
Meldahl, located at the Meldahl Locks and Dams, will be the largest of the four projects. The powerhouse will use three 35-MW bulb-type turbines with a total rated capacity of 105 MW and gross annual output of around 559 million kWh. AMP is developing the Meldahl project with the member community of Hamilton, Ohio, which originally procured the development license from the Federal Energy Regulatory Commission. Hamilton retains the right for around 52 percent of the energy produced from the project, with AMP taking the remaining output for the 48 other AMP members participating in the project.
Meldahl also has some parts that are not interchangeable with the other dams, according to Pete Crusse of AMP, as it has a four-blade runner compared to three-blades at the other sites.
|Each project had to be designed based on its location and challenges. The Willow Island project is the only of the four projects to only use two turbines because of its location farther upriver.|
Unique challenges on each site
Because of the nature of hydropower projects and the differences in the existing dams, a different engineering approach was required for each site.
“In each project, you have unique challenges you have to overcome,” Crusse said. “Willow Island, for example, required an archeology dig. At the Smithland project, we knew one of the biggest risks on that particular project was the fact it sat right on a fault line and there could be some underground stabilization of the ground that we had to take care of. But each of them has unique risks, and I’d say the majority of that risk is getting to the point where you can start placing the concrete.”
Smithland also sits on karst, which is a very soluble and uneven bedrock, Blaszczyk said. Although Meldahl and Willow Island are founded on rock, the other two are not.
“At Smithland and Cannelton, the rock is quite deep,” Blaszczyk said. “So those power plants are founded on the alluvial foundations. Making sure those stay put and that they can appropriately support the powerhouse long term required some innovative technical solutions and doing some things that were quite challenging.”
Crusse also noted the different turbine designs – each site has a different capacity, and Willow Island, which is located farthest upriver and has less flow than the other three projects, is a two-turbine facility rather than a three-turbine facility.
Although MWH is serving as the owner’s engineer on all four projects, each has a different contractor building the power plant and installing the owner furnished equipment used at the sites.
Building the four power plants at the same time did create some advantages for AMP.
“We wanted to maximize the repeatability from project to project, and to get the best price, we wanted to order in bulk,” Blaszczyk said. “We did a contract for the Cannelton, Smithland and Willow Island projects for the turbine generator equipment all at once. Ultimately, we signed three discrete contracts with that vendor, but the pricing was developed as a package so we could maximize the economy of scale. We ended up with about 14 different contracts on each of the projects, ranging from turbine generators to the cofferdams for the project.”
The projects do share some similar characteristics that allow for a shared knowledge base.
“You would have lessons learned from each of the projects, and the ones that are in the lead are generally the ones that are plowing the trail,” Crusse said. “As they plow the trail, they encounter things that impact the schedule, and therefore you want to take that lesson and implement it as quickly as possible on the other three projects to make sure you don’t do the same thing twice.”
Perhaps more important than creating a uniform design, however, was making sure uniform system of management is in place, Crusse said.
“We have been extremely focused on consistency as an owner in managing these projects all the same,” he said. “That has been a big challenge because when you’re dealing with the size of staff on these projects, you’re dealing with a lot of very, very intelligent people. They all come to the job site and want to do some things or build things or manage things or administer things all differently. When that happens, that sometimes can create chaos in the construction industry, so as a leader I made it extremely clear when we come to a decision on how we’re going to administer or manage something, it’s done the same on every one of the four projects, and that has worked out.”
Although hydropower makes up 7 percent of total U.S. electricity generation and is the country’s largest source of renewable energy, a recent study by the U.S. Energy Department and its Oak Ridge national Laboratory recently released a renewable energy resource assessment estimating over 65 GW of potential new hydropower development is available, nearly doubling the current U.S. hydropower capacity.
“The United States has tremendous untapped clean energy resources and responsible development will help pave the way to cleaner, more sustainable and diverse energy portfolio,” U.S. Energy Secretary Ernest Moniz stated at the time the assessment was released.
New hydropower builds in the U.S. have been slow, however, for a variety of reasons, including a high upfront capital cost. Because of AMP’s experience with the Belleville project, however, Carson said the organization knew hydropower would be the best option for its strategy of creating new assets.
“That debt is going to be retired in 2025,” Carson said of the Belleville project. “Once that debt is retired, you’re looking at around 3 cent power. That will be probably one of the cheapest, if not the cheapest, resources in those communities’ portfolio. I think people are already recognizing the benefits and the intelligence of that investment. In 50 years, the debt is paid off, the power is cheap and there’s another 50 years to go in the life cycle of the plant. Someone is going to be sitting there saying, ‘Wow, 50 years ago some people made some really smart decisions that are benefitting us now.”
Carson is quick to point out those decisions were not made by AMP, but by the members of the organization that chose to participate in the projects.
“They already look smart, but they’re going to look a whole heck of a lot smarter down the road,” he said.
|Hydroelectric facilities have a higher upfront cost than many other sources of power generation, but provide extremely cheap power once the debt is serviced.|
Advantages of hydropower
Despite the high upfront capital costs of building a hydropower project, the facilities will have a benefit that can last 100 years or more.
“Our CEO has made the observation a number of times that these are long-term investments,” Carson said. “You don’t develop hydro if you’re looking for short-term gains because there is a larger upfront investment. On the other side of that equation, though, is the plant with maintenance, upkeep and equipment replacement lasts 80 to 100 years. And once the debt service is paid off, the power becomes extremely cheap because the fuel is free.”
The advantages are more than financial. With the U.S. Environmental Protection Agency focusing on carbon emissions, hydropower’s emission-free generation doesn’t’ carry the risk of uncertainty that exists with future environmental regulation.
Unlike other forms of renewable energy such as wind farms and solar power, hydropower also can be used as a baseload facility, supplying a predictable amount of power onto the grid.
“There is a lot of development going on in wind and solar and some other renewables, and I think the development of those what we call intermittent or variable renewables will fuel a need for more hydropower to help stabilize the grid with some of the issues that crop up when these intermittent renewables are becoming a larger portion of the generation portfolio,” said MWH Senior Vice President and Director of North America Operations for Energy and Industry Group Mario Finis. “Hydro can help balance out some of the impacts of the variability and frequency control. I think the development of wind and solar will actually create more of a demand of some of the hydropower projects that can be developed to help with grid stabilization.”
Building on existing structures
One of the things that helps mitigate the costs is the ability to put powerhouses onto existing structures. According to Finis, only about 3 percent of the approximately 80,000 dams in the U.S. have power generation facilities.
“I think that’s an opportunity that has become more widely recognized here in recent years,” he said. “Both the costs, time and environmental impact of building a new reservoir are recognized to be cumbersome. Taking advantage of the existing dams and reservoirs that are already in place for other purposes, for navigation or flood control or recreation or irrigation, using that existing infrastructure and just adding power generation facilities to those existing dams, is a more cost-effective way to do it.”
The project would be significantly different if AMP was looking at building a new dam on the Ohio River, Carson said, and would not likely be seriously considered.
“As I always like to point out, those dams on the Ohio River were built in the ’50s and ’60s. Any impact to the ecology of the river has long since been realized and overcome, so we’re not adding to that. We’re constructing the powerhouse adjacent to existing dams and diverting a portion of the water that would otherwise be flowing over those dams through our powerhouse.”
“Doing it right”
Despite the lack of current new builds, the attractiveness of hydropower as a long-term investment leads to the possibility of future builds in the U.S. AMP hopes to provide an example of how to take advantage of existing dams to build hydroelectric facilities.
“We sure as hell hope it does,” Crusse said of the prospect of AMP’s project spurring future hydroelectric growth in the U.S. “We want to be on the cover of Engineering News Record with a statement that says these guys got it right. We don’t want to be on the cover of Engineering News Record with a comment like you see there about every week with the things that go wrong. That’s not what our goal is. We absolutely have set our goals high.”
Crussesaid he is proud of the projects, and the organization’s ability to get all four of the projects online and generating quickly as possible. As the company continues building the facilities, more people are recognizing the great value provided by hydropower.
“You’d be astonished – and I really mean that word – at the comments I receive of, ‘Why hasn’t this been done a long time ago?'” Crusse said. “I’m blessed to be able to work on all four projects, as hectic as it might be.”More Power Engineering Issue Articles
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