curtailments

Curtailment is the reduction or restriction of an activity by design, often to preserve safety, reliability, or efficiency. The term is widely used in resource management, transportation, and industry, but it is especially common in energy systems, where it denotes lowering power output or consumption below what could be produced or used under current conditions.

In electricity markets, curtailment occurs when generation is reduced despite available resources, typically due to grid congestion, safety constraints, or system balancing requirements. It can be planned, such as to allow maintenance or to integrate variable renewables, or unplanned, arising from faults or forecast errors. Curtailment can affect producers (revenue loss) and may trigger compensation schemes or contractual penalties.

Causes include transmission bottlenecks, mismatches between supply and demand, priority for maintaining voltage or frequency, and market prices that make keeping generation uneconomical. Weather, outages, and insufficient storage or interconnections also contribute.

The environmental and economic effects of curtailment depend on what replaces the curtailed generation. If renewables are curtailed and fossil generation fills the gap, emissions may rise; if demand response reduces consumption or storage supplies energy more efficiently, impacts may be lower. Costs can accrue from wasted potential energy and contractual penalties.

Mitigation strategies focus on grid expansion and interconnections, advanced forecasting, energy storage, and demand-side management, which can reduce the frequency and volume of curtailment while preserving reliability and market efficiency.