Demand-side flexibility (DSF) enables electricity consumers to adjust consumption in response to price signals or system needs, whether through industrial load curtailment or shifting usage across hours at the retail level where incentives are in place.
DSF is not a uniform resource. Industrial loads, EV charging, electrolysers and residential demand each operate under different constraints and remain at varying stages of participation in ancillary and energy markets. In practice, activity to date has been concentrated in industrial loads, which account for the bulk of DSF services.
Europe’s grid fix is already on our roofs
As Europe’s power system becomes increasingly dominated by variable wind and solar generation, demand for flexibility is rising, with battery energy storage systems (BESS) often seen as the primary solution. Demand-side flexibility is also gaining traction, offering similar services in some markets without requiring significant infrastructure investment.
DSF’s key advantage: flexibility without new assets
Demand-side flexibility is less expensive to deploy than dedicated flexibility infrastructure because it leverages existing electricity consumption rather than new physical assets. Typically, industrial demand response requires load control systems, data-sharing upgrades and active energy management, rather than large capital investments.
For major energy consumers, the marginal cost of flexibility can be relatively low. Adjusting industrial processes or shifting consumption across hours can deliver flexibility without the need for new generation or storage capacity.
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However, this low-cost flexibility comes with one crucial limitation: availability is conditional. Industrial processes, production schedules and operational constraints all play a role in determining when demand can be adjusted. In contrast to batteries, demand response cannot always be dispatched whenever the system requires it.
Where DSF competes with BESS
Demand-side flexibility competes most directly with batteries in short-duration balancing services and capacity markets, with the strongest overlap in mFRR and, to a lesser extent, aFRR. These products allow activation over several minutes, aligning with most industrial demand-response portfolios. FCR participation is possible in some markets, but the 30-second activation requirement limits suitability for many loads unless automation or on-site storage is available.
Why coordination, not capacity, will define Europe’s next energy phase
Several European markets already show relevant DSF participation:
- Belgium allows DSF to participate in FCR, aFRR and mFRR
- France provides broad TSO market access through independent aggregators and a wholesale demand-response mechanism (NEBEF)
- Great Britain enables DSF participation across balancing and wholesale markets, with several active aggregators
- Poland allows DSF in ancillary services, but participation remains concentrated in capacity markets
Capacity markets are another area of overlap. Several European capacity mechanisms allow demand-side resources to participate alongside generation and storage assets. For example, around 1.6 GW of demand-side resources were contracted in Poland’s capacity market for 2025 delivery.
System-wide outcome: changing price formation
In theory, large-scale demand flexibility would shift consumption towards low-price periods and reduce peak scarcity events, thereby lowering day-ahead spreads. However, current market evidence does not support this effect at scale. Two main constraints explain this:
Limited exposure of demand to dynamic pricing. Across the EU, 73 percent of households remain on fixed-price electricity contracts, limiting incentives to adjust consumption in response to hourly price signals.
Concrete evidence of large-scale explicit DSF participation in wholesale energy markets is still scarce. France provides the clearest example of a functioning framework: RTE’s NEBEF/NEBCO mechanism allows curtailed loads to be sold into day-ahead, intraday and OTC energy markets, but annual MW/MWh participation data is not reported as transparently as capacity-market data. In Great Britain, independent aggregator access to the wholesale market only went live in November 2024 under P415, so there is not yet a long public track record of volumes.
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BESS deployment is scaling faster than DSF and is more effective per MW at impacting spreads due to faster response and higher cycling frequency. Batteries are therefore likely to compress intraday spreads first, with possible spillover into day-ahead markets as penetration increases, a dynamic already observed in more mature systems such as the US.
Scale lacking for market impact
Demand-side flexibility has long been positioned as a major flexibility resource, but its deployment at scale has been slower than expected, mainly due to regulatory fragmentation and insufficient market signals to unlock broader participation. For now, it remains conditional flexibility, dependent on industrial processes and consumer behaviour, while battery storage provides dedicated and fully controllable flexibility.
Expert analysis: Why flexibility is key for a future-proof energy system
Rather than replacing storage, demand-side flexibility is more likely to expand the overall flexibility ecosystem. In the near term, however, BESS will influence intraday price spreads before DSF, given its faster deployment and intrinsic purpose. (Nicolas Briet/hcn)
Join The smarter E Europe webinar Demand-side flexibility in action: real-world strategies for energy-intensive industries on 5 May 2026.
