The introduction of additional 15-minute products in the balancing power market marks an important step forward. From October 2026, additional quarter-hour products are to be introduced in the aFRR and mFRR markets alongside the existing 4-hour products.
For providers of flexible generation assets, this could open up new opportunities: flexibility can be tailored more precisely to individual time slots, controlled more accurately and offered in a more differentiated manner on the market.
This move is in line with the development of the electricity system. As the share of renewable energy grows, short-term fluctuations in generation and consumption are continuing to increase. At the same time, there is a growing need for installations that can respond quickly: battery storage systems (BESS), industrial loads, power-to-heat plants, electrolysers or even renewable generation plants with suitable control systems.
Why Shorter Product Time Slots are Relevant
Until now, providers have had to maintain their balancing capacity across longer product time slots. This works well for many conventional installations. However, for an increasingly renewable and decentralised energy system, this structure only reflects the actual availability of flexible assets to a limited extent.
In practice, flexibility is rarely available at a constant level over several hours. It depends on the state of charge of a storage system, on industrial production processes, on weather and generation forecasts, on intraday prices, and on technical and operational constraints.
15-minute products allow for a finer granularity of flexibility provision. Plants no longer necessarily have to offer their flexibility over several hours, but can be deployed in a more targeted manner in individual quarter-hour intervals. This can lower barriers to market entry and unlock additional flexibility.
Which Assets Stand to Benefit Most
The transition is of particular interest to battery storage systems. Their economic value stems from the optimal allocation across different markets, such as FCR, aFRR, mFRR, day-ahead and intraday. Shorter product time slots enable more precise decisions on when to reserve capacity for balancing power and when it is better to utilise the storage system in short-term trading.
The new product design may also be relevant for industrial loads. Many processes offer flexibility, but often only within clearly defined time windows. This applies, for example, to power-to-heat plants, electrolysers, refrigeration processes, pumps or other controllable consumers. Where flexibility is only available at short notice, 15-minute products are better suited to operational realities than rigid 4-hour blocks.
For renewable energy plants, this finer granularity also opens up new possibilities. Wind and PV generation can fluctuate significantly within a matter of hours. Shorter product durations can help to market the flexibility that is actually available in a way that more closely matches real-time generation.
Aggregation Remains the Key Challenge
The new design introduces additional complexity. This is because 15-minute bids are aggregated into synthetic 4-hour bids prior to the auction and treated as a single bid with an average price.
If volumes are missing in individual quarter-hours, aggregation may fail. In this case, bids are automatically rejected and do not enter the market.
For suppliers, this means that it is not enough to assess individual quarter-hours as economically attractive. The bidding logic must ensure that the necessary volumes are consistently available across the relevant quarter-hours. Forecasting, portfolio management and bid submission must be closely integrated.
This can prove particularly challenging for smaller portfolios or assets with highly fluctuating availability. Larger, diversified portfolios have structural advantages here, as they can balance availability across multiple assets.
Why Liquidity is Key to Success
Whether the 15-minute products gain a foothold in the balancing power market will depend heavily on liquidity. Only if sufficient supply is aggregated across the individual quarter-hours can the new product design give rise to an efficient market.
The introduction of quarter-hourly products will therefore also serve as a test of the maturity of flexibility trading. The market needs flexible generation assets, but also systems that reliably make this flexibility available at a high temporal resolution.
For Entelios, this development is a logical step. Energy markets are becoming more short-term, more granular and increasingly driven by forecasts. It is precisely in this environment that automated cross-market optimisation demonstrates its value.
Conclusion: Greater Precision, but also Higher Demands
The introduction of additional 15-minute products in the balancing power market is more than just an adjustment to the market design. It is a step towards an electricity system in which flexibility can be deployed more precisely and exploited more effectively from an economic perspective.
New opportunities are emerging for battery storage, industrial loads and renewable energy plants. At the same time, practical implementation will determine just how great the added value actually will be. Aggregation, liquidity and operational complexity will be key success factors.
This raises a clear question for flexibility providers: under these conditions, is the 15-minute product an attractive additional market, or will it initially remain a product for highly automated and diversified portfolios?
In your view, what role will 15-minute products play in the future?
