Dresden Generating Station Explained

Dresden Generating Station
Coordinates:	41.3897°N -88.2681°W
Country:	United States
Location:	Goose Lake Township, Grundy County, near Morris, Illinois
Status:	O
Construction Began:	Unit 1: May 1, 1956 Unit 2: January 10, 1966 Unit 3: October 14, 1966
Commissioned:	Unit 1: July 4, 1960 Unit 2: June 9, 1970 Unit 3: November 16, 1971
Decommissioned:	Unit 1: October 31, 1978
Cost:	Unit 1: $423 million (2010 USD) or $ in dollars Unit 2: $856 million (2010 USD) or $ in dollars Unit 3: $828 million (2010 USD) or $ in dollars
Owner:	Constellation Energy
Operator:	Constellation Energy
Np Reactor Type:	BWR
Np Reactor Supplier:	General Electric
Ps Cooling Source:	Direct open-cycle mode: Closed-cycle mode: Indirect open-cycle mode:
Ps Cooling Towers:	4 × Mechanical Draft (supplemental only)
Ps Units Operational:	1 × 902 MW 1 × 895 MW
Ps Units Manu Model:	Unit 1: BWR-1 (Mark 1) Units 2–3: BWR-3 (Mark 1)
Ps Units Decommissioned:	1 × 197 MW
Ps Thermal Capacity:	1 × 700 MW_th (decommissioned) 2 × 2957 MW_th
Ps Electrical Capacity:	1797
Ps Electrical Cap Fac:	98.13% (2017) 73.30% (lifetime, excluding Unit 1)
Ps Annual Generation:	15,447 GWh (2017)
Website:	Dresden Generating Station

Dresden Generating Station (also known as Dresden Nuclear Power Plant or Dresden Nuclear Power Station) is the first privately financed nuclear power plant built in the United States. Dresden 1 was activated in 1960 and retired in 1978. Operating since 1970 are Dresden units 2 and 3, two General Electric BWR-3 boiling water reactors. Dresden Station is located on a 953acres site in Grundy County, Illinois, at the head of the Illinois River, near the city of Morris. It is immediately northeast of the Morris Operation—the only de facto high-level radioactive waste storage site in the United States. It serves Chicago and the northern quarter of the state of Illinois, capable of producing 867 megawatts of electricity from each of its two reactors, enough to power over one million average American homes.

In 2004, the Nuclear Regulatory Commission (NRC) renewed the operating licenses for both reactors, extending them from forty years to sixty.^[1]

Unit 1

After the Atomic Energy Act of 1954 allowed private companies to own and operate nuclear facilities, Commonwealth Edison contracted with General Electric to design, construct, and place into operation the 192 MWe Dresden Unit 1 for $45M in 1955.^[2] One-third of the contract price was shared by a consortium of eight companies comprising the Nuclear Power Group Inc.

The BWR at GE's Vallecitos Nuclear Center and the AEC's BORAX experiments provided research data and operator training for Dresden.

The core contained 488 fuel subassemblies, 80 control rods, and 8 instrument nozzles. Each subassembly contained 36 fuel rods in a Zircaloy-2 channel. The fuel was uranium dioxide clad in Zircaloy-2 tube. The core thermal power was 626 MWt. The reactor vessel was rated to 1015 psia and measured 12 ft. 2 in. diameter and 42 ft. tall.

The reactor featured a dual cycle, with steam coming from both the stream drum and steam generators. This made for rapid response to changes in power demand. Reactor power was regulated by actuation of the secondary admission valve by the turbine's governor. Decreasing the rate of secondary steam reduces reactor power, and vice versa. Thus, the secondary pressure varies with the external load.

Cooling

The plant has three cooling modes:

Direct open-cycle mode: Intake from canal leading to the Kankakee River, discharge directly to the Illinois River. The cooling canal system, cooling lake, and the supplementary cooling towers are completely bypassed in this mode of operation.
Indirect open-cycle mode: Intake from canal leading to the Kankakee River, discharge to cooling canal leading to Dresden Cooling Lake, discharged from lake through return cooling canal that eventually discharges into the Illinois River. Use of the cooling towers for supplemental cooling of canal system water is usually necessary during this mode of operation.
Closed-cycle mode: Intake from return cooling canal leading back from Dresden Cooling Lake, discharge to cooling canal leading to Dresden Cooling Lake. Use of the cooling towers for supplemental cooling of canal system water is usually not necessary during this mode of operation.

It also has cooling towers

Electricity Production

Generation (MWh) of Dresden Generating Station^[3] !Year!Jan!Feb!Mar!Apr!May!Jun!Jul!Aug!Sep!Oct!Nov!Dec!Annual (Total)
2001	1,193,458	1,054,333	1,187,102	981,943	1,132,442	1,127,280	1,031,337	1,135,702	932,498	892,446	945,681	924,451	12,538,673
2002	1,234,842	1,108,990	1,059,816	1,186,361	1,210,951	1,176,948	1,133,199	1,210,328	1,097,968	797,663	1,223,682	1,145,176	13,585,924
2003	1,246,460	1,160,493	1,250,523	1,242,216	1,212,105	1,058,939	1,293,159	1,291,997	1,230,004	847,958	941,888	901,425	13,677,167
2004	1,216,081	1,157,391	1,286,564	1,113,658	954,565	1,250,516	1,294,621	1,075,250	1,006,250	1,131,669	1,176	858,976	12,346,717
2005	1,296,266	1,149,577	1,203,983	1,153,170	1,211,033	1,220,520	1,288,247	1,227,178	943,039	1,264,403	373,412	1,291,625	13,622,453
2006	1,295,498	1,164,240	1,292,561	1,248,987	1,281,759	1,245,263	1,232,623	1,284,318	1,246,890	1,290,115	568,728	1,291,064	14,442,046
2007	1,294,287	1,163,545	1,293,573	1,253,535	1,199,725	1,248,937	1,291,916	1,281,698	1,202,803	1,228,109	783,991	1,288,662	14,530,781
2008	1,085,546	1,211,845	1,289,661	1,252,854	1,292,759	1,248,659	1,291,802	1,283,863	1,092,984	1,208,852	832,043	1,293,977	14,384,845
2009	1,297,183	1,161,648	1,283,016	1,186,675	1,282,268	1,246,218	1,289,811	1,286,199	1,242,479	1,201,845	578,552	1,211,519	14,267,413
2010	1,307,507	1,180,006	1,301,495	1,254,920	1,282,526	1,248,695	1,283,631	1,282,172	1,248,247	1,185,775	712,494	1,305,655	14,593,123
2011	1,311,449	1,174,027	1,306,344	1,262,166	1,279,032	1,248,876	1,258,176	1,278,908	1,244,684	971,176	1,041,964	1,337,521	14,714,323
2012	1,346,736	1,251,071	1,320,626	1,281,096	1,297,546	1,265,316	1,259,150	1,265,070	1,140,079	1,262,012	862,794	1,250,504	14,802,000
2013	1,385,187	1,256,336	1,383,409	1,330,425	1,342,703	1,311,561	1,353,411	1,347,863	1,309,659	1,166,351	866,361	1,359,206	15,412,472
2014	1,372,469	1,258,105	1,384,760	965,983	1,265,939	1,314,171	1,359,344	1,353,622	1,296,753	1,237,769	936,656	1,383,369	15,128,940
2015	1,302,562	1,099,619	1,377,180	1,323,646	1,334,905	1,304,534	1,361,087	1,355,055	1,310,891	1,316,146	872,051	1,230,682	15,188,358
2016	1,392,370	1,295,151	1,360,106	1,320,647	1,329,951	1,299,800	1,350,994	1,328,256	1,240,328	1,185,785	969,514	1,370,991	15,443,893
2017	1,390,462	1,246,232	1,379,854	1,317,074	1,351,025	1,308,476	1,351,499	1,355,759	1,229,144	1,195,284	943,489	1,376,584	15,444,882
2018	1,395,679	1,255,218	1,374,523	1,329,334	1,336,410	1,281,471	1,337,561	1,343,205	1,275,664	1,190,411	1,057,082	1,361,577	15,538,135
2019	1,372,972	1,263,033	1,382,807	1,328,485	1,225,938	1,316,784	1,346,740	1,333,857	1,138,813	1,135,829	1,002,013	1,234,444	15,081,715
2020	1,284,207	1,302,119	1,380,077	1,299,281	1,348,037	1,304,960	1,339,834	1,236,024	1,290,826	1,139,730	1,170,837	1,382,956	15,478,888
2021	1,391,356	1,260,404	1,374,530	1,319,595	1,148,772	1,301,750	1,353,735	1,340,707	1,301,614	909,872	870,624	1,383,721	14,956,680
2022	1,394,155	1,257,900	1,375,753	1,256,880	1,343,351	1,292,553	1,289,656	1,344,736	1,299,094	1,251,188	920,098	1,383,586	15,408,950
2023	1,384,921	1,247,143	1,357,294	1,157,187	1,333,924	1,300,289	1,338,236	1,341,796	1,276,309	1,198,281	962,559
2024

Incidents

Between the 1970s and 1996, Dresden was fined $1.6 million for 25 incidents.

June 5, 1970: A false high pressure signal due to instrument failure on the Dresden II reactor pressure control system caused turbine valves to dump steam (a "turbine trip"), which in turn automatically initiated a SCRAM. Void collapse in the reactor water caused the reactor water level to drop, which resulted in an automatic increase in feedwater flow. The feedwater pumps then tripped on low suction pressure. One pump turned back on automatically when the low suction pressure signal reset, feeding water rapidly into the now lower-pressure reactor vessel. Water level in the reactor rose rapidly until water entered the main steam lines. At this point, the false high pressure signal disappeared. The turbine dump valves closed, increasing back pressure in the reactor vessel and slowing the feedwater inlet flow. Cooling reactor water temperature caused further void collapse. Reactor water level began to rapidly lower once again. This again automatically caused the feedwater system to increase the flow rate into the vessel, and began to raise reactor water level. As cooler feedwater was again rapidly pumped into the reactor, void collapse caused water level to lower. The feedwater system responded by increasing feedwater flow. However, the indicator needle on the water level recorder stuck, which caused the operator to assume level had stopped rising in the reactor. The operator began increasing feedwater flow in order to raise water level in the reactor, manually overriding the automatic control system. The operator never checked a second indicator that showed the increasing level. Reactor water level continued rising and flooded the main steam lines. Two minutes later, the operator tapped on the water level recorder and the water level needle became unstuck, at which point the operator began reacting to the now high water level by manually reducing feedwater flow. At this point, the operator manually opened a steam line relief valve to reduce rising reactor pressure. However, due to the earlier introduction of water into the main steam lines, a hydrostatic shock occurred in the steam lines, which caused a safety valve to open, admitting steam and water into the drywell causing drywell pressure to increase. This caused the initiation of safety injection systems, and for the next 30 minutes reactor water level and pressure seesawed as the operators attempted to stabilize the reactor. It was not until two hours later that reactor level, reactor pressure and drywell pressure were reduced to normal.^[4] The movie The China Syndrome bases its initial plot device on this event, with the needle becoming unstuck when the operator taps the recorder.^[5]
December 8, 1971: Events similar to the ones the year earlier on Dresden II occur on Dresden III.^[4]
May 15, 1996: Lowering water levels around the nuclear fuel in unit 3^[6] reactor's core prompt a shut down at Dresden Generating Station and placement on the NRC's "watch list" that merit closer scrutiny by regulators. Dresden was on the NRC watch list six out of nine years between 1987 and 1996, longer than any of the 70 other operating plants in the nation.^[7]
July 15, 2011: Plant declared an Alert at 10:16 a.m after a chemical leak of sodium hypochlorite restricted access to a vital area that houses plant cooling water pumps.^[8]

Surrounding population

The Nuclear Regulatory Commission defines two emergency planning zones around nuclear power plants: a plume exposure pathway zone with a radius of, concerned primarily with exposure to, and inhalation of, airborne radioactive contamination, and an ingestion pathway zone of about, concerned primarily with ingestion of food and liquid contaminated by radioactivity.^[9]

The 2010 U.S. population within of Dresden was 83,049, an increase of 47.6 percent in a decade, according to an analysis of U.S. Census data for msnbc.com. The 2010 U.S. population within was 7,305,482, an increase of 3.5 percent since 2000. Cities within 50 miles include Chicago (43 miles to city center).^[10]

Ownership

Both currently operating units are owned and operated by Constellation Energy following separation from Exelon, which also owns and is responsible for the decommissioning of Unit 1. Prior to August 3, 2000, all three units were owned by Commonwealth Edison.^[11] ^[12]

Seismic risk

The Nuclear Regulatory Commission's estimate of the risk each year of an earthquake intense enough to cause core damage to the reactor at Dresden was 1 in 52,632, according to an NRC study published in August 2010.^[13] ^[14]

Averted closure

In August 2020, Exelon announced they would close the plant in November 2021 for economic reasons, despite the plant having licenses to operate for about another 10 years and the ability to renew the licenses for an additional 20 years beyond that. On September 13, 2021, the Illinois state senate passed a bill subsidizing the Byron and Dresden nuclear plants,^[15] which Governor J. B. Pritzker signed into law on September 15,^[16] and Exelon announced it would refuel the plants.^[17]

External links

Web site: Dresden Nuclear Power Plant, Illinois . http://arquivo.pt/wayback/20090710070953/http://www.eia.doe.gov/cneaf/nuclear/page/at_a_glance/reactors/dresden.html. dead. July 10, 2009. August 22, 2008 . Energy Information Administration, U.S. Department of Energy (DOE). 2008-11-19 .
http://www.eia.gov/cneaf/nuclear/state_profiles/illinois/il.html#_ftn4
https://www.nrc.gov/info-finder/decommissioning/power-reactor/dresden-nuclear-power-station-unit-1.html
Web site: Dresden 2 Boiling Water Reactor . February 14, 2008 . Operating Nuclear Power Reactors . U.S. Nuclear Regulatory Commission (NRC) . 2008-11-19 .
Web site: Dresden 3 Boiling Water Reactor . February 14, 2008 . Operating Nuclear Power Reactors . NRC . 2008-11-19 .

Notes and References

Web site: Dresden and Quad Cities, Nuclear Power Stations — License Renewal Application. February 13, 2007. U.S. Nuclear Regulatory Commission (NRC). 2008-11-19.
Power reactors . U.S. Atomic Energy Commission, Technical Information . 1958-05-01 . 41–48 . 1 January 2020.
Web site: Electricity Data Browser . 2023-01-03 . www.eia.gov.
Book: 92nd CONGRESS . "This action was forbidden..." . 22 March – 10 April 1972.
Web site: Ebert . Roger . The China Syndrome Movie Review (1979) . Roger Ebert . 1979-01-01 . 2013-12-30.
https://www.nrc.gov/docs/ML0037/ML003706185.pdf NRC dispatches special inspection team to Dresden Nuclear Plant to review reactor shutdown on May 15 (RIII-96-17)
Web site: Dresden Plant Placed On Nrc Watch List Again - tribunedigital-chicagotribune . articles.chicagotribune.com . dead . https://web.archive.org/web/20150929133913/http://articles.chicagotribune.com/1996-06-26/news/9606260054_1_nuclear-power-plant-nuclear-regulatory-commission-station-manager . 2015-09-29.
Web site: NRC responds to alert to Dresden Nuclear Power Plant | FireDirect . 2013-05-05 . dead . https://archive.today/20130616152643/http://www.firedirect.net/index.php/2011/07/nrc-responds-to-alert-to-dresden-nuclear-power-plant/ . 2013-06-16 .
Web site: NRC: Backgrounder on Emergency Preparedness at Nuclear Power Plants . Nrc.gov . 2012-08-17 . dead . https://web.archive.org/web/20061002131207/http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/emerg-plan-prep-nuc-power-bg.html . 2006-10-02 .
Web site: 2011-04-14 . Nuclear neighbors: Population rises near US reactors . 2024-08-16 . NBC News . en.
United States General Accounting Office. Government Accountability Office. NRC's Liability Insurance Requirements for Nuclear Power Plants Owned by Limited Liability Companies. 8 May 2004. 16. United States General Accounting Office. 29 April 2018. PDF. 56982748. GAO-04-654. 2004398843.
Web site: Nuclear Regulatory Commission. Nuclear Regulatory Commission. Commonwealth Edison Company; Dresden Nuclear Power Station, Units 1, 2 and 3; Notice of Consideration of Approval of Application Regarding Proposed Corporate Restructuring and Opportunity for a Hearing. Federal Register. Office of the Federal Register. 29 April 2018. 31 August 2000.
Web site: 2011-03-16 . What are the odds? US nuke plants ranked by quake risk . 2024-08-16 . NBC News . en.
Web site: Archived copy . 2011-04-19 . https://web.archive.org/web/20170525170632/http://msnbcmedia.msn.com/i/msnbc/Sections/NEWS/quake%20nrc%20risk%20estimates.pdf . 2017-05-25 . dead .
News: Gardner. Timothy. 2021-09-13. Illinois approves $700 million in subsidies to Exelon, prevents nuclear plant closures. en. Reuters. 2021-09-26.
Web site: Gov. Pritzker Signs Transformative Legislation Establishing Illinois as a National Leader on Climate Action. live. September 26, 2021. Illinois.gov. https://web.archive.org/web/20210916125439/https://www.illinois.gov/news/press-release.23893.html . 2021-09-16 .
Web site: Passage of Illinois Energy Legislation Preserves Nuclear Plants and Strengthens State's Clean Energy Leadership. 2021-09-26. www.exeloncorp.com. en-US.