Power system operations and control: Difference between revisions

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Dispatch curve: full-size graph is better than nothing
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=== Dispatch curve ===
{{#chart:Example.Line.chart}}
{{Graph:Chart
|<!-- vAnnotationsValues={"text": "Expected demand", "x": 150}
| table=System lambda curve 1.tab
| hAnnotationsValues={"text": "System lambda", "y": 60} -->
| type=linear| xField=demand
| series="cost"
| title=Dispatch curve
| yZero= | xAxis=Demand (MW) | yAxis=Cost ($/MWh) | yMax= | yGrid=y | width= | legend=-
| vAnnotationsValues={"text": "Expected demand", "x": 150}
| hAnnotationsValues={"text": "System lambda", "y": 60}
| hideSource=true
| right
}}
The decisions ("[[economic dispatch]]") are based on the '''dispatch curve''', where the X-axis constitutes the system power, intervals for the generation units are placed on this axis in the ''[[merit order]]'' with the interval length corresponding to the maximum power of the unit, Y-axis values represent the marginal cost (per-[[MWh]] of electricity, ignoring the startup costs). For cost-based decisions, the units in the merit order are sorted by the increasing marginal cost. The graph on the right describes an extremely simplified system, with three committed generator units (fully dispatchable, with constant per-MWh cost):<ref name=psu/>
* unit A can deliver up to 120 MW at the cost of $30 per MWh (from 0 to 120 MW of system power);