Base load requirement is the minimum level of demand on an electrical supply system over
24 hours.
Base load power sources are those plants which can generate dependable power to consistently
meet demand.
They are the foundation of a sound electrical system.
Description
Baseload plant, is an energy plant devoted to the production of baseload supply.
Baseload plants are the production facilities used to meet some or all of a given region's
continuous energy demand, and produce energy at a constant rate, usually at a low cost
relative to other production facilities available to the system.
Examples of baseload plants using nonrenewable fuels include nuclear and coal-fired plants.
Among the renewable energy sources, hydroelectric, geothermal, biogas, biomass, solar thermal
with storage and ocean thermal energy conversion can provide baseload power.
Baseload plants typically run at all times through the year except in the case of repairs
or scheduled maintenance.
Hydroelectric power also has the desirable attribute of dispatchability, but a hydroelectric
plant may run low on its fuel if a long drought occurs over its drainage basin.
Each baseload power plant on a grid is allotted a specific amount of the baseload power demand
to handle.
The base load power is determined by the load duration curve of the system.
For a typical power system, the rule of thumb is that the base load power is usually 35-40%
of the maximum load during the year.
Peaks or spikes in customer power demand are handled by smaller and more responsive types
of power plants called peaking power plants, typically powered with gas turbines.
Whilst historically large power grids have had base load power plant to exclusively meet
the base load, there is no specific technical requirement for this to be so.
The baseload can equally well be met by the appropriate quantity of intermittent power
sources and peaking power plant.
Economics Power plants are designated baseload based
on their low cost generation, efficiency and safety at rated output power levels.
Baseload power plants do not change production to match power consumption demands since it
is more economical to operate them at constant production levels.
Use of higher cost combined-cycle plants or combustion turbines is thus minimized, and
these plants can be cycled up and down to match more rapid fluctuations in consumption.
Baseload generators, such as nuclear and coal, often have very high fixed costs, high plant
load factor and very low marginal costs.
On the other hand, peak load generators, such as natural gas, have low fixed costs, low
plant load factor and high marginal costs.
Typically baseload plants are large and provide a majority of the power used by a grid.
Thus, they are more effective when used continuously to cover the power baseload required by the
grid.
Base load power plant usage Nuclear power plants may take many hours,
if not days, to change their power output, although modern stations, and those in France,
can and do operate as load following power plants and alter their output to meet varying
demands.
Nuclear and coal power plants have low fuel costs.
Because they require a long period of time to heat up to operating temperature, these
plants typically handle large amounts of baseload demand.
Different plants and technologies may have differing capacities to increase or decrease
output on demand: nuclear plants are generally run at close to maximum output continuously,
while coal-fired plants may be cycled over the course of a day to meet demand.
Plants with multiple generating units may be used as a group to improve the "fit" with
demand, by operating each unit as close to peak efficiency as possible.
See also
Capacity factor Energy demand management
Grid energy storage Load balancing
Smart grid Load following power plant
Peaking power plant References
External links Base Load Power Plants - Fundamentals of Electricity
Levelized Costs of Electricity Production by Technology
The Energy Resources and Economics Workbook