arXiv subjects

Lars Herre

Publications and source records attributed to Lars Herre.

5 recordsLinked to original sources

arXiv2025

Understanding Risk and Revenue in the Nordic 15-minute mFRR market: An EV Aggregation Study

Decarbonisation, decentralisation, and intermittency are driving the development of flexibility markets towards shorter market time units (MTU). Shorter MTUs and shorter gate closures lower the entrance barriers of demand side aggregators that face significant uncertainty on longer time scales. We study the business case for aggregated EV fleets participating in the Nordic 15-minute mFRR Energy Activation Market (EAM). Motivated by increasing system granularity and rapid EV uptake, we represent fleet flexibility as a virtual battery with time-varying power and energy envelopes and formulate a risk-aware stochastic optimisation that co-ordinates day-ahead scheduling with quarter-hour mFRR bidding. Using synthetic residential charging cohorts and observed day-ahead prices on two stylised days, we compare an independent day-ahead baseline to a co-optimised strategy under conservative availability and a CVaR-augmented objective. Across both price cases, co-optimisation increases expected profit and lowers downside risk: the model buys less energy day-ahead and shifts procurement toward mFRR down while flattening the charging plan to retain eligibility for mFRR up. Profit decomposition shows that the uplift is driven by higher mFRR down revenues and reduced reliance on unwinding day-ahead positions. We discuss operational implications for bidding and outline two extensions: rolling 45-minute re-optimisation and a V2G framework.

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arXiv2023

Network-Aware Flexibility Requests for Distribution-Level Flexibility Markets

This paper proposes a method to design network-aware flexibility requests for local flexibility markets. These markets are becoming increasingly important for distribution system operators (DSOs) to ensure grid safety while minimizing costs and public opposition to new network investments. Despite extended recent literature on local flexibility markets, little attention has been paid to quantifying the flexibility required at each location, considering physical network constraints (e.g. line and voltage limits). The method introduced uses a chance-constrained optimization model and a LinDistFlow approximation to consider both physical network constraints and uncertainty caused by renewable production or demand fluctuations. Unlike other methods, it avoids sharing sensitive grid data with the market operator. We compare our approach against a stochastic market-clearing mechanism which serves as a benchmark, and we derive analytical conditions for the performance of our method to determine flexibility requests. We show on two case studies that our method outperforms the stochastic market-clearing benchmark in terms of computation time while achieving comparable social welfare and costs for the DSOs. One of the case studies is conducted on an actual German distribution grid, showing that the proposed method can scale well to real-sized networks.

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arXiv2021

Reliability-Aware Probabilistic Reserve Procurement

Current reserve procurement approaches ignore the stochastic nature of reserve asset availability itself and thus limit the type and volume of reserve offers. This paper develops a reliability-aware probabilistic approach that allows renewable generators to offer reserve capacity with reliability attributes. Offers with low reliability are priced at lower levels. The original non-convex market clearing problem is approximated by a MILP reformulation. The proposed probabilistic reserve procurement allows restricted reserve providers to enter the market, thereby increases liquidity and has the potential to lower procurement costs in power systems with high shares of variable renewable energy sources.

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arXiv2021

Design of a Continuous Local Flexibility Market with Network Constraints

To the best of our knowledge, this paper proposes for the first time a design of a continuous local flexibility market that explicitly considers network constraints. Continuous markets are expected to be the most appropriate design option during the early stages of local flexibility markets, where insufficient liquidity can hinder market development. At the same time, increasingly loaded distribution systems require to explicitly consider network constraints in local flexibility market clearing in order to help resolve rather than aggravate local network problems, such as line congestion and voltage issues. This paper defines the essential design considerations, introduces the local flexibility market clearing algorithm, and -- aiming to establish a starting point for future research -- discusses design options and research challenges that emerge during this procedure which require further investigation.

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arXiv2021

A bottom-up quantification of flexibility potential from the thermal energy storage in electric space heating

Non-generating resources such as thermostatically controlled loads (TCLs) can arbitrage energy prices and provide balancing reserves when aggregated due to their thermal energy storage capacity. Based on a performed survey of Swedish single- and two-family dwellings with electric heating, this paper quantifies the potential of TCLs to provide reserves to the power system in Sweden. To this end, dwellings with heat pumps and direct electric heaters are modeled as thermal energy storage equivalents that can be included in a linear two-stage problem formulation. We approach the operational flexibility of the TCLs by modeling a risk-averse aggregator that controls decentralized TCLs and aims to maximize its own profit. The results show a potential of 2 GW/0.1Hz averaged over a year, and up to 6.4 GW/0.1Hz peak capacity. Based on a sensitivity analysis we derive policy implications regarding market timing and activation signal.

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