Day-ahead electricity markets are inefficient due to their coarse discretisation of time and their representation of electricity production and consumption in energy per time interval. This leads to excessive costs and infeasible schedules in the market clearing results. Some real-world systems have increased the resolution to improve accuracy, but this comes at a high computational cost. We propose an alternative, based on using linear power trajectories in the day-ahead scheduling process, which represent the momentary electricity production. Changing from a traditional energy-based to such a power-based formulation of the scheduling method can reduce cost by several percentage points, leading to a cost reduction of millions of euros in real-world systems on a yearly basis. Attempting to do so by increasing the resolution of the schedule would be accompanied by large increases in computational demands. Furthermore, we provide market design options to implement power-based bidding and pricing in day-ahead electricity markets, showing that pricing and market rules which encompass existing markets are readily available for implementation, and illustrate these with examples.@en

Large controllable loads, such as electric vehicles, are increasingly penetrating electricity distribution feeders. To avoid local congestion, their consumption behaviour must be steered, for which a real-time price propagated down from the transmission system does not suffice, as it does not reflect local grid conditions. To efficiently steer the charging of EVs by multiple self-interested parties, we propose an auction framework which accounts for local grid conditions, the limited flexibility of EVs, and the uncertainty inherent to small-scale networks. We formulate the EV charging problem as a job scheduling problem for self-interested aggregators, and auction network capacity
for discrete time slots using sequentially-cleared auctions, which run in parallel. We simulate this auction on a local network using realistic data for EV driving behaviour and network capacity, showing this method leads to feasible allocations which are fairer in case one party is weaker than the other due to size or information asymmetry.@en

In order to cope with fluctuations and uncertainty, power systems rely on contracted reserves. The day-ahead Unit Commitment (UC) is the short-term planning process which is commonly used to schedule these resources at minimum cost, while operating the system and units within secure technical limits. This paper shows through the evaluation of deterministic cases that conventional energy-based UC formulations lead to inefficient use of reserves in real-time operation to deal with completely known deterministic events. These inefficient decisions are inherent to the assumptions underlying the energy-based formulation, and the misaligned incentives between markets and real-time operation. Economic efficiency and system security can be improved by adopting a UC formulation which explicitly considers the instantaneous power trajectories of generators.@en