Spent Nuclear Fuel Storage. Congressional Research Service. NRC U. Independent Spent Fuel Storage Installations. WNA Chernobyl Accident Holt, M. Cite as:. Nuclear power plants are a type of power plant that use the process of nuclear fission in order to generate electricity. They do this by using nuclear reactors in combination with the Rankine cycle , where the heat generated by the reactor converts water into steam , which spins a turbine and a generator.
Aside from the source of heat , nuclear power plants are very similar to coal-fired power plants. However, they require different safety measures since the use of nuclear fuel has vastly different properties from coal or other fossil fuels. They get their thermal power from splitting the nuclei of atoms in their reactor core, with uranium being the dominant choice of fuel in the world today.
Thorium also has potential use in nuclear power production, however it is not currently in use. Below is the basic operation of a boiling water power plant , which shows the many components of a power plant, along with the generation of electricity. The reactor is a key component of a power plant, as it contains the fuel and its nuclear chain reaction , along with all of the nuclear waste products.
The reactor is the heat source for the power plant, just like the boiler is for a coal plant. Uranium is the dominant nuclear fuel used in nuclear reactors, and its fission reactions are what produce the heat within a reactor.
Although Ecofys acknowledges that the resource depletion cost is difficult to calculate since the scarcity of a finite natural resource is already reflected in its market price, and could therefore just as well be zero, a high estimate was asserted using a questionable methodology and without taking account of the potential for recycling nuclear fuel. Pricing of external benefits is limited at present. As fossil fuel generators begin to incur real costs associated with their impact on the climate, through carbon taxes or emissions trading regimes, the competitiveness of new nuclear plants will improve.
This is particularly so where the comparison is being made with coal-fired plants, but it also applies, to a lesser extent, to gas-fired equivalents.
The likely extent of charges for carbon emissions has become an important factor in the economic evaluation of new nuclear plants, particularly in the EU where an emissions trading regime has been introduced but which is yet to reflect the true costs of carbon emissions. Prices have stayed relatively low within the national and sub-national jurisdictions that currently put a price on carbon emissions.
In order to provide reliable electricity supply, there must be reserve capacity to cover refuelling or maintenance downtime in plants which are producing most of the time, and also provision must be made for backup generation for intermittent wind and solar plants at times when they are unable to operate.
Provision must also be made to transmit the electricity from where it is generated to where it is needed. System costs are external to the building and operation of any power plant, but must be paid by the electricity consumer, usually as part of the transmission and distribution cost. From a government policy point of view they are just as significant as the actual generation cost, but are seldom factored into comparisons of different supply options, especially comparing base-load with dispersed intermittent renewables such as solar and wind.
In fact the total system cost should be analysed when introducing new power generating capacity on the grid. Any new power plant likely requires changes to the grid, and hence incurs a significant cost for power supply that must be accounted for.
But this cost for large plants operating continuously to meet base-load demand is very small compared with integrating intermittent renewables into the grid. For nuclear and fossil fuel generators, system costs relate mainly to the need for reserve capacity to cover periodic outages, whether planned or unplanned.
The system costs associated with intermittent renewable generation relate to their inability to generate electricity without the required weather conditions and their generally dispersed locations distant from centres of demand.
The integration of intermittent renewable supply on a preferential basis despite higher unit cost creates significant diseconomies for dispatchable supply, as is now becoming evident in Germany, Austria and Spain, compromising security of supply and escalating costs. This has devastated the economics of some gas-fired plants in Germany, for instance. In some countries, market design results in a market failure wherby reliable and low carbon , but capital-intensive technologies such as large hydro and nuclear cannot be financed because long-term power purchase contracts are not available, meaning there is no certainty that investments can be recouped.
The overall cost competitiveness of nuclear, as measured on a levelized basis see figure below on Comparative LCOEs and System Costs in Four Countries , is much enhanced by its modest system costs. However, the impact of intermittent electricity supply on wholesale markets has a profound effect on the economics of base-load generators, including nuclear, that is not captured in the levelized cost comparisons given by the International Energy Agency IEA - Nuclear Energy Agency NEA reports.
The negligible marginal operating costs of wind and solar mean that, when climatic conditions allow generation from these sources, they undercut all other electricity producers. The increased penetration of intermittent renewables thereby greatly reduces the financial viability of nuclear generation in wholesale markets where intermittent renewable energy capacity is significant.
See also Electricity markets section below. The integration of intermittent renewables with conventional base-load generation is a major challenge facing policymakers in the EU, in certain US states and elsewhere. Until this challenge is resolved, e. When market designs create potentially unreliable supply systems that have to be fixed by setting up additional markets for stand-by capacity and other grid stability services, costs that should be borne by electricity generators where competitive pressures will act as a restraining factor have effectively been externalized.
In some countries, their market design results in a market failure whereby reliable and low-carbon but capital-intensive technologies such as large hydro and nuclear cannot be financed because long-term power purchase contracts are not available — so there is no certainty that investments can be recouped.
See also paper on Electricity Transmission Grids. Nuclear-specific taxes are levied in several EU countries. In June the Swedish government, amid growing concerns over the continued viability of existing plants, agreed to phase out the tax on nuclear power from onwards.
In Germany, a tax was levied on nuclear fuel that required companies to pay per gram of fuel used over six years to It is a downstream tax on energy delivered to non-domestic users in the UK introduced in Initially levied against fossil fuels and nuclear, the government removed renewables' exemption in its July Budget.
In the government introduced a carbon floor price — a mechanism that has long been seen as fundamental to the economics of new UK nuclear power. See also paper on Energy subsidies and external costs. The economics of any power generation depends primarily on what each unit kWh, MWh costs to produce for the consumer who creates the demand for that power. This is the LCOE as outlined above.
But secondly it depends on the market into which the power is sold, where the producer and grid operator run into a raft of government policies often coupled with subsidies for other sources.
Such policies raise the question of what public good is served by each, and whether overall the public good is optimized. Where the outcome is not maximising public good effectively, there is market failure. A market can work well to achieve its stated objectives, but still result in market failure. This is often explained by externalities — negative or positive impacts of an industry — that are not reflected in the market.
With electricity, the direct private costs of generating power at the plant do not usually include the external costs e. Electricity markets rely on direct or private costs at the plant to dispatch i. Those costs determine merit order of dispatch.
Meeting real-time electricity demand is a difficult and challenging process. The electricity markets do this, but do not reflect the externalities of the generators participating in the market and may result in market failure. An electricity market with efficient short-term spot prices should not be expected to achieve other objectives such as lower emissions, long-term system reliability, or implementation of national policy.
Merchant generating plants rely on selling power into a commodity market which is shaped by policies including those which may favour particular sources of power regardless of their immediate and longer-term deficiencies in relation to the public good.
Generating plants in a regulated or government-owned electricity industry can deliver power essentially on a cost-plus basis, with regulators or governments able to reflect externalities in decisions.
Nuclear power plants provide a range of benefits to society that are not compensated in the commodity electricity market revenue stream. These public benefits include emission-free electricity, long-term reliable operation, system stability, system fuel diversity and fuel price hedging, as well as economic benefits from employment. Generic approaches to fix market failure include imposing costs on negative externalities such as CO 2 emissions, providing compensation to support positive externalities, and government ownership of sectors likely to experience market failure.
Some US states make zero-emission credit ZEC payments to nuclear generation to reward the positive externalities. ZECs are similar to the production tax credits applying to wind power, though lower, but are based directly on estimated emission benefits. They mean that the value of nuclear electricity can be greater than the LCOE cost of producing it in markets strongly influenced by low gas prices and subsidies on intermittent wind generation which has market priority.
Without the ZEC payments, nuclear operation may not be viable in this situation. An analysis by the Brattle Group in showed that zero-emission credits for nuclear power could secure the economic viability of nuclear plants in competition with subsidized renewables and low-cost gas-fired plants. Sustaining nuclear viability in the interim will reduce near-term emissions, and is a reasonable and cost-effective insurance policy in the longer term.
The majority vote was reported to be on three main criteria: grid reliability, reducing carbon emissions, and maintaining jobs. These show: advanced nuclear, 9. Among the non-dispatchable technologies, LCOE estimates vary widely: wind onshore, 5. The nuclear LCOE is largely driven by capital costs.
At low discount rates it was much cheaper than wind and solar PV. Solar PV increased 2. LCOE figures omit system costs. Accordingly, nuclear energy scientists are bringing new tools to the table that will enable them to understand fuel behavior down to the microstructure and grain level.
Laser-based thermal conductivity measurements, electron microscopy, nuclear magnetic resonance spectroscopy, and X-ray diffraction and absorption are all techniques being adapted for work on radioactive fuels to help scientists pin down how fuel properties are affected by different parameters, such as fuel microstructure or grain size and reactor power or temperature.
Sometimes, for example, a slightly higher temperature releases stresses or strains. There is also significant interplay between experiment and computational calculations. By the time a nuclear fuel is prepared, irradiated, cooled, and analyzed, a single experiment can take up to seven years to complete. Even as nuclear scientists try to make the harnessing of nuclear energy ever more efficient, a renaissance of nuclear energy still has many political, regulatory, and financial hurdles to overcome, not to mention the need for a waste repository in the U.
World energy needs are not decreasing, however, so researchers should see the fruits of their labors come to life over the next few decades in new reactors that rely on highly productive and reliable fuels.
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