With increasing renewable energy and cross-sectoral electrification price volatility is increasing. Flexibility through demand-side management and electric storage has the potential for reducing price volatility. In this thesis, using duality theory the flexibility required for constraining price to a maximum limit is quantified. Coordination Strategies for Reducing Price Volatility in Local Electricity Markets investigate three case studies varying with respect to type and degree of flexible resource aggregation for constraining price. Insights generated are relevant for regulators, aggregators, energy communities, and scholars focusing on the engineering and economics of local energy systems.@en

Recently, given the increased integration of renewables and growing uncertainty in demand, the wholesale market price has become highly volatile. Energy communities connected to the main electricity grid may be exposed to this increasing price volatility. Additionally, they may also be exposed to local network congestions, resulting in price spikes. Motivated by this problem, in this paper, we present a coordination mechanism between entities at the distribution grid to reduce price volatility. The mechanism relies on the concept of duality theory in mathematical programming through which explicit constraints can be imposed on the local electricity price. Constraining the dual variable related to price enables the quantification of the demand-side flexibility required to guarantee a certain price limit. We illustrate our approach with a case study of a congested distribution grid and an energy storage system as the source of the required demand-side flexibility. Through detailed simulations, we determine the optimal size and operation of the storage system required to constrain prices. An economic evaluation of the case study shows that the business case for providing the contracted flexibility with the storage system depends strongly on the chosen price limit.

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Price volatility in electricity markets could significantly increase as a result of the increase in demand due to the electrification of heating and transport and intermittent power generation from large scale integration of renewable energy sources. In some parts of the grid, price volatility may be even more extreme due to congestion. Energy storage and price responsive demand provide a potential source of flexibility to reduce excessive variations in price. In this paper, we investigate the potential of one such type of price responsive demand, namely thermostatically controlled loads, to mitigate against this adverse economic effect through a coordination mechanism that gives explicit constraints on the local electricity price. In a simulation based study that focuses on an energy community situated in a congested part of the distribution grid, we investigate to what extent thermostatically controlled loads can provide load reduction in order to cap prices at a specified limit. Results show that congestion and the resulting price spikes can effectively be mitigated by exploiting the thermal inertia of the households.

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The integration of a high share of solar photovoltaics (PV) in distribution networks requires advanced voltage control technologies or network augmentation, both associated with significant investment costs. An alternative is to prevent new customers from installing solar PV systems, but this is against the common goal of increasing renewable energy generation. This paper demonstrates that solar PV curtailment in low voltage areas can be reduced and fairly distributed among PV owners by centrally coordinating the operation of PV inverters. The optimal inverter active and reactive power operation points are computed by solving a multi-objective optimization problem with a fairness objective. The main results show that fair optimal inverter dispatch (FOID) results in less power curtailment than passive voltage regulation based on Volt/VAr droop control, especially at high solar PV to load ratios. The effectiveness of the model is demonstrated on a residential low voltage network.

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Recently, the volatility associated with marginal prices has increased due to large scale integration of renewable generation. Price volatility is undesirable from a consumer perspective. To address this issue, we present a framework for hedging that uses duality theory for quantifying the amount of demand-side flexibility required for constraining marginal prices to the consumers maximum willingness to pay for electricity. Using our formulation, we investigate the ability of an Energy Storage System (ESS), as a demand-side flexibility source, to hedge against electricity price volatility across a multi-time period horizon while accounting for its intertemporal constraints. Additionally, we analyze the economical benefit that operating the ESS under information forecasts brings to the consumers.

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Locational Marginal Price (LMP) is a dual variable associated with supply-demand matching and represents the cost of delivering power to a particular location if the load at that location increases. In recent times it become more volatile due to increased integration of renewables that are intermittent. The issue of price volatility is further heightened during periods of grid congestion. Motivated by these problems, we propose a market design where, by constraining dual variables, we determine the amount of demand-side flexibility required to limit the rise of LMP. Through our proposed approach a price requesting load can specify its maximum willingness to pay for electricity and through demand-side flexibility hedge against price volatility. For achieving this, an organizational structure for flexibility management is proposed that exhibits the coordination required between the Distribution System Operator (DSO), an aggregator and the price requesting load. To demonstrate the viability of our proposed formulation, we run an illustrative simulation under infinite and finite line capacities.

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The large-scale integration of renewables to the electrical grid is resulting in the increase of price volatility in electricity markets. This increase is undesirable from both electricity producer and consumer perspectives. In this paper, we present a framework that allows consumers to hedge against the price volatility. Using optimization duality theory, we quantify the amount of demand-side flexibility that an Energy Storage System (ESS) is required to provide for constraining marginal prices to a consumer's maximum willingness to pay for electricity. The ESS is operated using Model Predictive Control (MPC) and depends on renewable generation forecasts. Forecast uncertainties are accounted through probabilistic constraints that are applied on the ESS operation. Probabilistic constraints enable the Energy Storage Operator to set a priori robustness guarantees on the solution which are cheaper than robust approaches. Through simulations it is demonstrated that the formulation is able to successfully hedge against price volatility considering uncertainty.

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DC distribution grids are an option for future smart grids in order to directly connect distributed energy resources like photovoltaics, storage, electric vehicles and loads that already use dc internally. Due to the increased installed power capacity, voltage deviations and line congestion are likely to occur. Exact optimal power flow with locational marginal prices (LMP) is a way of tackling this problem.In this paper a fully distributed solution for the exact optimal power flow problem in dc distribution grids is presented. It uses the consensus and innovations approach and includes line losses as well as line current limits and over- and under-voltage bounds. Zero marginal cost and linear cost functions for generators and loads are possible in addition to quadratic cost functions. A simulation example shows initial results on a 4-node test network.

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The EU has set ambitious targets for an energy transition. While research often focuses on technology, institutions or actors, a transition requires complex coordination and comprehensive analysis and design. We propose a framework accounting for technology, institutions and actors' perspective to design in socio-technical systems. We present its application, firstly, to biodiesel production in Germany; secondly, to vehicle-to-grid contracts in a Car as a Power Plant microgrid. We show how using the framework as the core in modelling can contribute to the performance improvement of these systems. Future work will elaborate on the next generation of thermal energy systems, coordination control of microgrids and implementing flexibility through demand response aggregation. Overall, designing solutions to the problems described calls for comprehensive engineers who look beyond the technical design and deal with multi actor socio-political processes including institutional consideration.@en