Nuclear Power Aspects • Health Hazards of not Going Nuclear • Understanding the “waste” issues • Load Following capabilities – can they? • Status of Nuclear Technology • Economics
Health Aspects • Radiation in perspective: • Living in Denver – add 350 mrem • TMI accident – add 1 mrem, replacement power for TMI2 produced by coal fire will result in more cancer deaths. • Annual background radiation (average) by natural sources in the US – 131 mrem • X-ray dose – about 100 mrem • Maximum amount of dose allowed to be received by someone who lived at a nuclear power plant boundary for 1 year – add 5 mrem • Coast to Coast jet flight – add 5 mrem
Energy Generation Technology Comparison for Greenhouse Gas Emissions Source: "Life-Cycle Assessment of Electricity Generation Systems and Applications for Climate Change Policy Analysis," Paul J. Meier, University of Wisconsin-Madison, August, 2002
Emissions Produced by 1 kWh of Electricity Based on Life-Cycle Analysis Source - Hydropower-Internalised Costs and Externalised Benefits; Frans H. Koch; International Energy Agency (IEA)-Implementing Agreement for Hydropower Technologies and Programmes; Ottawa, Canada, 2000
Waste? • Some radioactive isotopes last for thousands, millions of years. However, lethal doses of chlorine, phosgene, ammonia, cyanide produced in the US alone exceed those of nuclear “waste”. Also, some chemical poisons such as arsenic, lead and mercury last forever. • Spent Fuel is recyclable and reusable. • Interim dry storage – safe for decades. • Long term depository – needed in the US and elsewhere. • Reprocessing is expensive technology but Japan, France are using this now. • Nuclear “waste” is preferable than waste from coal plants; radioactive wastes are manageable and can be secured whereas waste spewed into the atmosphere of fossil fired plants isn’t controlled. • Coal plants have radioactive emissions due to radium and thorium in the coal. These radio-nuclides are dispersed into the atmosphere through the plant stack.
French Experience • 59 operating nuclear reactors • Just over 63 GWe capacity, supplying almost 80% of country’s demand • In 2005 French electricity generation was 549 billion kWh net and consumption 482 billion kWh - 7700 kWh per person. Over the last decade France has exported 60-70 billion kWh net each year. • France has some plants that follow load on a daily basis, as well as some which shutdown on the weekends only. • French government policy starting in the mid 70’s was to expand rapidly the country's nuclear power capacity. Nuclear energy, with the fuel cost being a relatively small part of the overall cost, made good sense in minimizing imports and achieving greater energy security. • France now claims a substantial level of energy independence and almost the lowest cost electricity in Europe. Over 90% of its electricity is nuclear or hydro.
Nuclear Plant Load Following Capabilities • Load following part of the original design of current operating fleet. • Load following common in France. • New reactor designs will be similarly designed - AP 1000 Example: • The AP1000 is designed to be capable of startup from cold shutdown to hot standby in 24 hours. • Similarly, it is capable of cooling down from reactor critical to the condition of refueling operation in 24 hours. • The AP1000 is designed for a 24-hour load cycle with the following profile (subject to achieving full power fuel conditioning at the beginning of the fuel cycle): • Starting at 100% power, power ramps down to 50% power in 2 hours, • Power remains at 50% for 2 to 4 hours, • Power ramps up to 100% in 2 hours, • Power remains at 100% for the remainder of the 24 hour cycle. • Also designed to respond to grid frequency changes. • In terms of power output modulation, the AP1000 is capable of satisfying peak-to-peak power demand changes of 10% of the plant rating at 2% of the plant rating per minute. This capability is provided within the power operating range of 15 to 100%.
Load Following – Myth or Truth • In the US, the existing nuclear power plants are currently being operated as a base load source of power. • Nuclear is most often the lowest cost choice of power. • Nuclear energy provides only about 20% of the United States electricity – so being the lower cost choice, means it is not the first choice to back down. • The nuclear industry has defined excellence, in part, as safely generating electricity as evidenced by good capacity and generation metrics. In other words, 100% capacity and generation are the hallmarks of good power plant operations. This focus drives the culture for keeping the plants on line as “base load”. The nuclear industry has a continuously improving culture, so there has been increasing preference to stay at 100%. Even so, grid controllers will ask plants to ramp given certain grid reliability needs, and the plant is required to respond and is in fact, capable of responding. • There is less opportunity for human error when the plant operators are watching the plant parameters at 100% power versus having to manipulate the controls in moving the plant up or down in power.
Economics • Economies of Nuclear Operations are dependent on electric output, plant reliability, short refueling outages. • Construction costs – Improvements in the process promise reduced or at least accurate construction cost projections. • World experience • One-step licensing process • Design Certification • Modular design, construction and installation • Refer to Joe Turnage slides at the June 28th CEC workshop.