Tom Henry
Commentary
There’s been a lot of speculation about how near-shore energy production will evolve in the coming years throughout the Great Lakes region, but especially between Detroit and Cleveland – the region’s most densely populated shoreline.
That strip of land is where one of the nation’s greatest policy debates is being played out.
That’s not only because of all of the people there. It’s also because the area, loosely defined as the western Lake Erie basin, also may have the Great Lakes region’s most myriad issues pertaining to fish and wildlife habitat, water quality, water usage and climate change effects on anything from agriculture to beach recreation.
Some changes are real and are happening now.
New federal rules on coal-fired power plants, as well as the anticipation of a global fracking bonanza, have shifted energy markets toward natural gas.
One example of that is a large natural gas plant planned in the Toledo suburb of Oregon, Ohio. If built, it could surpass FirstEnergy Corp.’s Davis-Besse nuclear plant along the Lake Erie shoreline for energy production. At present, there appear to be no major permitting obstacles.
A smattering of wind turbines exist along or near the shoreline at sites such as the Great Lakes Science Center in Cleveland and Clay High School in Oregon.
They anger birders because their presence is viewed as a challenge: Many biologists don’t want turbines within three miles of a Great Lakes shoreline, at least not until more is known about how lethal they are to birds, bats and other creatures.
There’s also the anticipation of the region’s first offshore wind farm being developed three miles north of the Cleveland shoreline someday.
Wind power has gone far beyond the boutique or novelty stage, yet it is still unlikely to ever become the dominant form of energy production – especially in densely populated areas such as western Lake Erie.
One of the newest developments is the announcement that Rudolph/Libbe, Inc., plans to install massive solar arrays on a brownfield site in South Toledo and generate enough energy to cover nearly a third of the nearby Toledo Zoo’s electricity needs. The zoo’s eastern edge is practically a stone’s throw from the Maumee River, one of Lake Erie’s most important tributaries.
A lot of attention is focused on nuclear power.
In Michigan’s Monroe County, just south of Detroit, DTE Energy is still assessing market conditions and deciding whether to build a new breed of reactor, Fermi 3, on its Fermi complex along western Lake Erie.
That is likely to continue for at least a few more years, as its license application works its way through the review process. The utility will likely continue to operate its existing plant, Fermi 2, for years.
The Davis-Besse plant in northern Ohio’s Ottawa County is also cooled by the shallow water of western Lake Erie.
Despite what anti-nuclear activists say, there is little reason to believe that plant will shut down anytime soon, either.
Recent developments at the San Onofre nuclear complex in Southern California have fueled hopes of a shutdown by the opposition movement.
Southern California Edison stunned many industry observers by announcing it is giving up on plans to restart its two San Onofre reactors. The site has been fraught with problems since a radioactive steam leak caused extensive damage to its new steam generators, installed in 2009 and 2010 at a cost of $670 million.
FirstEnergy is planning to install two new steam generators at Davis-Besse in 2014.
Steam generators generate electricity from the steam that produced by pressurized-water reactors. They are among the largest and most expensive parts of a nuclear plant. They usually are only replaced once during a plant’s life.
Barring an unforeseen development, Southern California Edison’s decision to shutter its two San Onofre reactors could do more to keep Davis-Besse open than to close it.
While anti-nuclear activists are sounding an alarm, there’s no correlation between what happened at San Onofre, what has happened elsewhere, and what will happen at Davis-Besse next year – other than San Onofre had substantial problems installing its steam generators.
According to the Nuclear Energy Institute, 57 reactors have replaced their steam generators since 1980.
None, the NEI said, have experienced the same issues as San Onofre.
A U.S. Nuclear Regulatory Commission spokesman, Scott Burnell, said the San Onofre case had “tube-to-tube wear behavior never before seen.”
It was, in many ways, an anomaly.
Does that mean there’s been only one problem out of 57 replacement projects? No.
The Crystal River nuclear plant in west-central Florida was shuttered in February after unrepairable cracks developed in its containment when it was cut open for new steam generators.
Davis-Besse has cracks in its outer containment shield, which differs from Crystal River’s. Davis-Besse’s is a double-layered shield.
Davis-Besse’s cracks, confined to its exterior, have been attributed to wind and ice storms, especially those from the blizzard of 1978. It was weather-sealed last year.
There are numerous cases of leaking steam-generator pipes, many between the 1970s and 1990s.
But the NRC has attributed those leaks to an inferior alloy that was used when the plants were built. The metal pipes that are accessible are gradually being replaced by metal that doesn’t corrode or deteriorate as fast.
Nuclear supplies 20 percent of the nation’s electricity.
Just this year, the two San Onofre reactors, plus single ones at Crystal River and the Kewaunee nuclear plant in Wisconsin have been removed from service. The latter was largely because of economics, driven by the falling price of natural gas and other factors.
A number of other nuclear plants have been idle for an extensive time for repairs, such as the Fort Calhoun plant in Nebraska.
That means an awful lot of energy has been removed from the nuclear equation at a time America is growing and its needs are increasing.
Davis-Besse soon hopes to get its 20-year license extension, which would allow it to remain in operation through April, 2037.
There are no certainties in Great Lakes energy production.
But one could argue that the events in Southern California and elsewhere have simply raised the bar on the need for better NRC oversight and stronger industry involvement in Davis-Besse’s 2014 steam generator replacement project.
That’s an intangible worth noting when one considers that David Lochbaum, Union of Concerned Scientists nuclear safety project director, believes steam generator projects “got less and less oversight” as the NRC and the nuclear industry shifted its attention more to security issues after the Sept. 11, 2001 terrorist attacks, the modern era of license renewals and applications to build new nuclear plants, and other more emerging issues.
No doubt the NRC and the nuclear industry are aware of what’s at stake for Davis-Besse and the Great Lakes region when the plant’s steam generators are replaced next year.
San Onofre and other events are reminders of the need for energy diversity.
Removing San Onofre “was a blow to California’s energy diversity, but is not an indicator of the industry’s larger ability to reliably supply low-carbon electricity to hundreds of millions of electricity consumers from facilities operating in 31 states,” the NEI said.
Nuclear and coal are still a big part of our nation’s energy picture. They will be for years, even if market forces continue to shift toward other forms of energy.
That transition is healthy, especially for Ohio, which for years has had more than four out of every five megawatts of electricity generated in the state come from coal-fired power plants – well above the national average.
But as the region – and the country – look for ways to gradually diversify its energy production and further protect its shorelines, one can expect some existing forms of power to remain in place to help ease the transformation.
In case you missed it
On June 20, the U.S. Senate unanimously approved legislation to protect more than 32,000 acres of Michigan’s Sleeping Bear Dunes National Lakeshore as wilderness. The bill, authored by U.S. Sen. Carl Levin (D., Mich.) and co-sponsored by U.S. Sen. Debbie Stabenow, reaffirms protections put in place in 1982. It calls for 13 years of shoreline planning efforts by area residents, the National Park Service, and Congress to be put into effect. The goal is to protect habitat from development while facilitating more access to beaches, trails, and streams.
I can understand that an electrical engineer would call a nuclear power plant’s generator a “steam generator” since, in your field, I presume you classify generators by the energy source. A nuclear plant uses different nomenclature, however. In that context a steam generator means a specific piece of equipment that is little more than a shell-and-tube heat exchanger.
The error in the article was clearly not calling the electrical generator a steam generator. He clearly was referring to the actual steam generators since he referenced the San Onofre problems. Those problems were related to that plant’s steam generators and not their electrical generators. He also mentions that Davis-Besse’s steam generators will be replaced next year, which is true (the electrical generators will not be replaced). So everything he said about steam generators is correct except for the sentence that states that they generate electricity. The correct statement would have been that steam generators act as a boiler, and the resulting steam is used elsewhere to generate electricity.
As for your last question, I am not terribly familiar with design considerations for steam generators and turbines. My work focuses almost entirely on what is happening in the reactor core. I do know that one advantage of the PWR design compared to a boiling water reactor (BWR) is that the coolant which flows into the turbine is not the coolant which flowed through the core. PWRs have two different coolant loops, one containing the core and one containing the turbine. The two loops exchange heat in the steam generator, but the coolant in these loops does not mix. So a PWR’s turbine blades should not be exposed to radioactive material. BWR’s on the other hand, have no steam generator. In those plants, water boils in the reactor core and the steam is sent directly to the turbines. So those blades can be exposed to radioactive material if any is released into the coolant. This does factor into the design and maintenance of BWR turbines, but I’m not sure how much.
Dan, I’ve never worked on a project as such. If I was bringing in a steam turbine to generate electricity at a nuclear plant, the metalurgy of that turbine’s components would only take into consideration the purity of the evaporate that constitutes the steam and the operating temperature (talking outside of specifications). From what I can see, the actual steam generator’s metalurgy would be of a higher standard. Does radioactivity come into play on the integrity of the materials being used?
Dan, I’m an electrical engineer. In my field every generator is an electrical generator. It’s not uncommon for people to refer to an electrical generator as a steam generator. Mr. Henry clearly stated the steam generators generate electricity and the PWR’s generate steam. If Mr. Henry made a mistake in the article, it seems to me that it’d be coming from the aspect of people calling an electrical generator a steam generator. The easy mistake. Having suggested the mistake comes from terminology does not make me wrong. I’m well aware of how generators work. I’m thinking from the perspective of Tom writing an article.
Joe, I’m sorry to say but you are wrong. Steam generators and electrical generators are two entirely different things. Both are present but perform very different functions in a pressurized water reactor (PWR) like Davis-Besse or San Onofre. The fact that they both have the word “generator” in their name does not imply a similarity in their function beyond the fact that they are both generating something. To use your tissue analogy, this would be like confusing facial tissue with muscle tissue simply because they are both called tissues.
An electrical generator like those present in any thermal power plant uses steam to generate electricity. Steam enters a turbine system and turns the turbine blades. The turbine blades are connected to a magnet which spins inside a coil of copper wire. The shifting magnetic field creates a current in the wire which is the electricity we use in our homes.
A steam generator uses high temperature water to create steam. It is simply a large heat exchanger; it has more in common with a radiator or a tea kettle than it does any electrical device. You said if you need steam, you’d use a boiler. But that is all a steam generator is. It is a very large boiler used to create steam.
The water in a PWR’s primary loop–the loop that contains the reactor core–enters the steam generator and flows through small tubes. This primary loop water is enters at a very high temperature (typically over 600 degrees F) but stays liquid because it is highly pressurized. Water in the secondary loop–the loop that contains the turbines–flows over those tubes, and the heat from the primary coolant moves into the secondary coolant. The secondary coolant boils because is at a lower pressure and thus has a lower boiling point than the primary coolant. The secondary coolant leaves the steam generator as steam and is piped from there to the turbines. No electrical generation takes place at all within the steam generator; all that happens is secondary loop water boils and becomes steam.
The steam generator performs the same function as a boiler in a coal power plant or the reactor core in a boiling water reactor nuclear plant (where water boils within the core itself).
You would not say that the boiler at a coal power plant is the component that uses steam to generate electricity. The accurate statement would be to say that the boiler creates steam which is used elsewhere in the plant to generate electricity. The same is true for steam generators in PWRs–they do not generate electricity, but rather they create steam which is used elsewhere in the plant to generate electricity.
BTW, I am a nuclear engineer.
Generators generate electricity (energy). This generator does it using steam. So you call it a steam generator. On the other hand, if you need steam, you use a boiler. It’s not proper language usage, but is accepted since most people speak in terms of the product being applied as opposed to the concept. Most people know what you mean when you ask for a Kleenex as opposed to facial tissue. Either way, you hope to quickly receive a product akin. Not to say pressurized-water reactors aren’t more important to public safety.
Your description of the function of steam generators is completely wrong. They do not generate electricity, they generate steam (hence the name). The steam generated there is sent to the turbines. Electrical generators attached to the turbines are what generate the electricity.
I don’t mean to emphasize nuclear energy, but I’m sure the Davis-Besse plant has a cooling pond to separate from Lake Erie. Since nuclear energy doesn’t have carbon emissions, it is very “green”. That is not to say other renewable energy sources aren’t viable, but solar and wind energy aren’t more efficient than coal. As leroy mentioned with http://greatlakesecho.org/2013/03/27/wind-power-on-the-rise-in-the-great-lakes-region/ since wind energy is unpredictable, it creates a load (fights), negating electricity being produced at other electrical generating facilities. Until something can be found to generate energy with a lesser effect on global warming, nuclear energy will be the main contender. This seems to be implied by the article. And I have to apologize to Mr. Barrett because he is correct about the ice boom. But hydroelectricity is extremely environmentally friendly. As a need for humans, I think it supersedes biological concerns (global warming). However, I only condone it where you need a reservoir to keep water for human consumption or control the effects of flooding or dry seasons downstream. When you open up the dam, why not draw a few watts out of it.
Re: Tom Henry Energy Generation Summary
Most useful collection of fact-based data on the challenges and opportunities for future electric generation sources in the next 20-30 years. Well done, Tom!