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Building Turbines to Boost the Efficiency of Existing Nuclear Plants

  • Alstom S.A. is a global company with nearly $30 billion in annual revenues. It provides equipment, technology and services for power generation, rail transportation, and power transmission.
  • Within its power generation business, the company builds “turbine islands,” the portions of nuclear power plants that convert steam produced by nuclear reactors into electricity. Thirty percent of the world’s nuclear power plants use Alstom turbines.
  • In April 2011, the company opened a new 350-employee plant in Chattanooga, TN, to build its most advanced steam turbines and gas turbines, including its largest steam turbine, the ARABELLE™, which ranges in size from 900 to 1,800 megawatts (MW). This new plant is Alstom’s third facility in the state.
  • Management views a U.S. manufacturing presence as very important for serving the large North American market.

Big Turbines, Big Company

On April 8, 2011, Alstom Power shipped the first two nuclear steam turbine rotors via river from its new facility in Chattanooga, TN. The rotors, bound for a nuclear power plant in Illinois, were so massive - 15 ft. tall, 35 ft. long and 130 tons each - they could only be transported by river barge.2 The company's new steam turbine and gas turbine manufacturing plant, where the rotors were built, is equally huge. The 350,000 ft2 facility features the world's largest horizontal lathe and rotor balancing facility (used respectively for constructing and testing turbines) and North America's two largest indoor cranes.3 Its construction cost $330 million and, at full capacity, will require a staff of 350 people to operate.

Bob Hilton, Alstom's Vice President of Power Technologies for Government Affairs, believes the United States is very competitive in this sort of heavy, highly technical manufacturing. "People confuse [manufacturing for] the stuff that's in Walmart," said Mr. Hilton. "When you're talking about real equipment, in terms of power, manufacturing and automobiles, we still make that stuff here."

Alstom provides power generation equipment for a full range of energy sources including coal, natural gas, nuclear, wind, geothermal, solar thermal and hydro. The group is headquartered in France and also manufactures equipment for rail transportation and power transmission. The power business is Alstom S.A.'s largest subsidiary, generating more than 50% of the firm's revenue in 2009 and 2010.4 Alstom S.A. has a large U.S. presence, with over 6,000 employees in 45 states and the District of Columbia. The company enjoys a large share of the power generation equipment and services market for each of the aforementioned energy technologies, including nuclear power. More than 40% of the world's 450 operating nuclear power plants use Alstom-made equipment of some kind. Alstom is also the world's leading supplier of turbine islands for nuclear power plants.5

 

Alstom's Presence in the Nuclear Power Market

Alstom does not build nuclear reactors. Rather, the company builds the "turbine islands" for nuclear power plants - the turbines, generators, heat exchangers, pipes, and other components that take steam created by the reactor and use it to generate electricity. Alstom's turbine island offerings include the world's largest nuclear steam turbines, the ARABELLETM family of turbines, and the world's largest generators, the GIGATOP line. The ARABELLETM nuclear steam turbines are so large compared to steam turbines found in coal-fired power stations that they spin at ‘half-speed' (measured in revolutions per minute [RPM]) to avoid undesirable aerodynamic turbine blade behavior, minimize steam-path erosion and keep within material stress limits. Alstom's nuclear steam turbines are highly reliable, only contributing to forced outages approximately 1/10th as often as the average steam turbine in the United States.6

At the Chattanooga facility, Alstom builds steam turbines from 900 MW to 1,800 MW, which can be customized for use with any reactor type. The company also makes a range of natural gas turbines at the plant, including its largest and most efficient gas turbine, the GT24.

 

The Nuclear Power Market Today: A Focus on Life Extension

In 2010, nuclear power provided 13.5% of the world's electricity.7 In the United States, nuclear power supplies about 20% of the country's electricity.8 However, due to debates about the technology's safety and profitability, very few new nuclear plants have been built in the last 20 years, particularly in the United States. Today, half of U.S. nuclear plants are over 30 years old, and nearly all are over 20.9 With new nuclear plant construction in the U.S. facing an uncertain future, the main opportunity for Alstom lies in retrofitting these existing plants with new steam turbines to improve their efficiency and extend their operating lives (provided it can be done safely). Turbine islands are an important part of this strategy; upgrading to more efficient equipment can increase a plant's output by as much as 20%.10

Extending the lifespan of existing nuclear plants and improving their efficiency offers the potential for low-cost, low-emissions electricity because the largest costs of nuclear plants are for initial development and construction. In comparison, operating costs, including fuel costs, are relatively low. Most U.S. nuclear plants began with a license to operate for 40 years and as of March 2011, around two-thirds of them had filed applications to have their licenses renewed.11,12 "The core issue is: ‘How do we maintain and improve the existing nuclear fleet?'," said Mr. Hilton. The company has already retrofitted 103 nuclear facilities worldwide.

 

Building the Technology in America

One reason Alstom chose to build large steam turbines and gas turbines in Tennessee is the availability of low-cost transport by river. Through its location along the Tennessee River, Alstom's Chattanooga plant can access 70-80% of the country's nuclear plants.13 Barge transport is preferred over land options for the movement of massive steam turbines. On top of that, "if you can make it locally, you are going to," said Mr. Hilton, commenting on the benefits of manufacturing in-country as opposed to manufacturing overseas and shipping the units to the United States. Another advantage is the ability to specialize in the 60Hz turbines used in North America (as well as Japan, Brazil, and a few other countries), rather than the 50Hz models used in Europe, China and most of the rest of the world.14 In addition to selling turbines domestically, Alstom plans to export turbines from the Chattanooga facility to all of the major 60Hz markets.

Beyond these practical reasons, the company also seems to like operating in Tennessee, where it and its heritage predecessor companies have had a presence dating back to 1900. Alstom has another 600-employee boiler plant in Chattanooga, and a 500-person engineering and research group in Knoxville, TN. The reason, says Mr. Hilton, is two-fold: American manufacturing is extremely strong in high-tech and capital-intensive goods, and American markets demand a lot of power. "Manufacturing is a long way from dead in America," said Mr. Hilton. "We have to build more and new power plants, [and] we have to upgrade how we deliver power. The United States is fundamentally the soundest market there is, so Alstom will always be here."

Oct 2011

Endnotes

1. Alstom reports financial data for the year-end March 31. "2010," as used here, refers to the period March 31, 2010 - March 31, 2011. Other financial data is referenced similarly.

2. "130-Ton Turbine Rotors Leave Alstom Chattanooga in Factory's First River Delivery," Alstom Company
Website, August 8, 2011, http://www.alstom.com/us/news-and-events/news/first-turbines-leave-alstom-chattanooga-for-river-delivery (October 31, 2011).

3. Ibid.

4. See Endnote 1.

5. "Alstom cements its position as a leading provider of conventional islands for nuclear power plants," Alstom Press Release, June 18, 2008, 
http://www.alstom.com/power/news-and-events/press-releases/Alstom-cements-its-position-as-a-leading-provider-of-conventional-islands-for-nuclear-power-plants-20080618 
(October 31, 2011).

6. Alstom Nuclear Activity, "ARABELLE: The leading nuclear steam turbine," July 2010, p. 5.

7. "World Statistics: Nuclear energy Around the World," Nuclear Energy Institute, September 2011, http://www.nei.org/resourcesandstats/nuclear_statistics/worldstatistics/ (November 1, 2011).

8. "State Nuclear Profiles," U.S. Energy Information Administration (EIA), September 2010, http://www.eia.gov/cneaf/nuclear/state_profiles/nuc_state_sum.html (November 2, 2011).

9. Steve Hargreaves, "Half of U.S. nuclear reactors over 30 years old," CNN Money, March 15, 2011, http://money.cnn.com/2011/03/15/news/economy/nuclear_plants_us/index.htm (November 1, 2011).

10. International Energy Agency (IEA), "Technology Roadmap; Nuclear Energy," 2010, http://www.iea.org/papers/2010/nuclear_roadmap.pdf (November 1, 2011), p. 11.

11. "Frequently Asked Questions: How old are U.S. nuclear power plants and when was the last one built?," EIA, March 31, 2011, http://205.254.135.24/tools/faqs/faq.cfm?id=228&t=21 (November 1, 2011).

12. As of March 2011, 63 of the Nation's 104 reactors had received extensions on their 40-year life, and 28 were in the process of filing an application.

13. Alstom Company Website, loc. cit.

14. 60Hz and 50Hz refers to the frequency of the alternating current of the electric grid. Rotating machinery such as steam turbines, gas turbines and electric generators need to spin at different speeds for each of the two frequencies, and thus have slightly different designs for each.

15 Mike Pare, "Alstom set to produce new natural gas turbine in Chattanooga," Times Free Press, September 16, 2011, http://timesfreepress.com/news/2011/sep/16/alstom-set-produce-new-natural-gas-turbine/ (November 3, 2011).