When Grand Gulf Nuclear Station in Port Gibson began its 17th refueling outage earlier this month, it took its first step towards making history. While the usual work is taking place — maintenance, replacing spent fuel, troubleshooting, etc. – Grand Gulf employees are also laying the foundation for a $510 million project upgrade that will make the reactor the most powerful nuclear generating unit in the nation.
The upgrade, approved by the state Public Service Commission in December 2009, will increase Grand Gulf’s output by approximately 178 megawatts (MW), a 13 percent increase above current production levels of 1,265 MW.
Grand Gulf came online in July 1985. The project originally included plans for two reactors, estimated to cost $1.2 billion, but cost overruns of 400 percent caused a single reactor to cost more than $3.5 billion. Entergy customers — 433,000 people in 45 counties — are still paying for their share of the plant.
The project was a multi-state project. After appeals that reached the U.S. Supreme Court, Mississippi was ordered to absorb 33 percent of the cost, approximately $1 billion. The original rate shock of the plant was almost 60 percent, which was phased in over 15 years. The highest adder to base rates was 53 percent, which occurred between March and September 1994.
Customers are still being billed approximately $150 million per year for the reactor, said Virden Jones, Mississippi Public Utilities Staff director of Electric, Gas and Communications. “But it is the cheapest energy we have now” due to low fuel costs, he said.
Approximately 53 MW from the upgrade will directly benefit Entergy Mississippi’s customers. The additional generation will produce enough energy to power up to 53,000 more Mississippi homes.
The company expects the influx of reliable and low-cost energy to greatly offset the initial project costs, “resulting in little-to-no impact on customers’ electricity bills,” Entergy said in a statement.
Completion of the upgrade project is scheduled for late 2012 following the scheduled refueling outage in the spring.