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libertad
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Is there any limitation for an NPP to work in 75% of power for a while eg. 3 or 4 months?
If so should be any changes in calculations documents?
If so should be any changes in calculations documents?
I'm not sure what you are asking here. Are you asking about licensed Rx thermal limits?libertad said:If so should be any changes in calculations documents?
Fermi 2 recently spent several months at 60% power, and some PWRs have had reduced power operation. It's usually undesirable economically, but it can be done. The fuel in the core does become deconditioned, or conditioned at the lower power, so power ascension should be done per operating restrictions for fully deconditioned fuel.libertad said:Is there any limitation for an NPP to work in 75% of power for a while eg. 3 or 4 months?
If so should be any changes in calculations documents?
libertad said:Is there any limitation for an NPP to work in 75% of power for a while eg. 3 or 4 months?
If so should be any changes in calculations documents?
Hiddencamper said:The biggest limitation is typically economics. Due to the large O&M cost of maintaining a nuclear plant, it is typically best to operate them at full power.
There may be other limitations based on the specific plant design. For example, in boiling water reactors, typically when operating at less than full power, there are changes to the MCPR penalties. As power decreases the MCPR penalties increase. This penalty is offset by the fact that you are operating at reduced power, however sometimes it may require a change to the control rod sequence in order to ensure that adequate margin to thermal limits remain.
montoyas7940 said:I'm not sure what you are asking here. Are you asking about licensed Rx thermal limits?
I can't comment on PWRs but a BWR can run at reduced power indefinitely. In the USA extended power reductions are sometimes required to meet EPA thermal pollution limits.
libertad said:consider it as PWR. about calculations documents I mean Safety Justification reports and Album of neutronics and physics parameters of core.
NPP stands for Net Primary Productivity. It is a measure of the rate at which plants convert solar energy into biomass through photosynthesis. NPP is important because it is the basis of all ecosystems and provides the energy and resources necessary for all other organisms to survive.
There are several limitations to NPP working at 75%. The first is that it assumes that all ecosystems are functioning at the same level of productivity, which is not always the case. Additionally, it does not take into account other factors such as nutrient availability, water availability, and temperature which can greatly impact NPP. Lastly, NPP working at 75% does not account for changes in land use and human activities that can affect NPP.
NPP is calculated by subtracting the rate at which plants use energy through respiration from the rate at which they produce energy through photosynthesis. This calculation takes into account the amount of solar radiation, temperature, and water availability in a given ecosystem. It is typically measured in units of energy per unit area per unit time, such as grams of biomass per square meter per year.
In recent years, there have been changes to the calculation of NPP to account for different limitations and factors. These changes include incorporating satellite data to measure photosynthetic activity, using remote sensing techniques to estimate vegetation cover, and incorporating data on temperature and precipitation to better estimate NPP in different regions. Additionally, there have been efforts to standardize the methods used for calculating NPP to improve accuracy and comparability across studies.
NPP is used in a variety of scientific research studies, including climate change research, ecosystem management, and agriculture. It is used to understand the functioning of ecosystems and how they respond to environmental changes. NPP is also used to estimate the amount of carbon stored in vegetation and to assess the impact of human activities, such as deforestation, on the carbon cycle. Overall, NPP is an important measure for understanding and managing the health and productivity of our planet's ecosystems.