E.A. Martínez Ceseña

Contribution of Microgrids to distribution network reliability

The current development of distribution networks into active and smarter systems has been facilitated by the integration of novel technologies such as Microgrids (MGs) and Distributed Energy Resources. These new concepts are expected to bring about significant economic benefits at the distribution level in the form of network reinforcement deferral and increased reliability levels, among others. In this context, this paper aims at shedding light on the impacts that the use of MGs for post-contingency distribution network management can have on reliability. For this purpose, a reliability assessment tool based on sequential Monte Carlo Simulations (MCS) is presented and used for the evaluation of a real distribution network, while a framework to implement the MG services is also proposed. The results show that reliability improvements for MG users can be remarkable, while external network users and the network operator also perceive benefits. The former experience higher reliability levels, and the latter experience lower network reinforcement needs when connecting additional customers due to the services provided by MGs.

Energy efficiency at the building and district levels in a multi-energy context

Increasing environmental concerns are encouraging new building energy efficiency (EE) concepts defined as reductions in net consumption of electricity, heat, gas and/or other energy vectors. Thanks to the smart grid paradigm, this is increasingly being achieved via the installation of low carbon technologies. However, this approach can be severely limited due to the physical and technical constraints of particular buildings (e.g., limited space to install technologies and limited energy network connection capacity). This paper proposes a more effective approach by explicitly including all relevant multi-energy flows in the EE concept and extending its scope to the district level. This paradigm shift allows energy flows to be produced and consumed in the most effective locations. The benefits from extending the scope of different EE concepts (e.g., based on electricity, electricity and heat, and all vectors) from the building to the district level are illustrated with a real UK multi-energy system.

Techno-economic assessment of distribution network reliability services from microgrids

This paper proposes a new techno-economic framework for the optimisation of Microgrid (MG) operation considering energy and reserve services, as well as a novel distribution network reliability service. The price signals required to incentivise reliability services are formulated based on the potential of MGs to improve reliability levels. This potential is quantified based on sequential Monte Carlo simulations and economic values assigned to reliability according to existing UK regulation. The results, based on pragmatic MG data and a real distribution network, highlight strong synergies between reliability services, and energy and reserve services. These synergies allow MGs to provide distribution network reliability support without significantly changing their normal behaviour or compromising their capabilities to provide other services.

Operational optimization and environmental assessment of integrated district energy systems

This paper presents a new approach to assess and improve the environmental and economic performance of integrated electricity and heat district energy systems in light of (i) optimal operation of available multi-energy components (e.g., cogeneration and heat pumps) and (ii) energy exchanges within the district through internal electricity and heat networks. The latter is particularly attractive as, instead of constraining energy flows within each building, it enables the production and consumption of energy in the most attractive locations (e.g., in buildings that can accommodate photovoltaic panels). The proposed methodology is formulated as a mixed integer linear programming problem, and demonstrated with a real UK district comprising internal electricity and heat networks and several buildings. The results highlight the attractiveness of optimising multiple energy vectors, particularly in light of energy exchanges between buildings, in economic and environmental terms.

Chapter Six – Business Cases

Chapter 6 introduces the Business Case (BC) assessment process for Energy Positive Neighborhoods (EPNs) developed as part of the COOPERaTE project. The BC is introduced as the primary metric for assessment of EPNs, and indeed, any intervention in a liberalized energy system. The BC assessment process is then presented, which produces quantitative metrics for BC evaluation, before the network aspect of energy systems is discussed, and a value mapping method to quantify the impact of EPN BCs on other energy system actors is detailed. The process is demonstrated through two case studies, before concluding remarks on the chapter are given.

Barriers, Challenges, and Recommendations Related to Development of Energy Positive Neighborhoods and Smart Energy Districts

Abstract This chapter presents an overview of the barriers to smart, demand-side interventions for neighborhoods and districts. Barriers are classified as political/regulatory, economic, social, and technological. Subsequently, drawing on experience from the COOPERaTE project, the specific challenges for the implementation of the Energy Positive Neighborhood (EPN) concept are reviewed. These challenges are presented in classifications of: energy modeling and simulation, performance assessment, information technology, and business model development. Finally, recommendations to aid implementation of the EPN concept and, more generally, smart district and demand-side interventions are detailed.

Energy Positivity and Flexibility in Districts

Abstract This chapter examines the concept of energy positivity and argues that energy positivity, in the classical sense (i.e., districts that generate more electricity than they consume), is not a suitable objective or metric for Energy Positive Neighborhoods (EPNs), or smart energy districts more generally. Instead, it is argued that flexibility is a more suitable objective/metric, given the various variable and dynamic factors which effect electricity systems, and that, in a liberalized system, economic value is the most suitable proxy for flexibility. Through quantitative case studies, the economic value of the classic definition of energy positivity and of flexibility is examined to demonstrate the nonequivalence of these objectives, before suggesting how the economic value metric can be made a better proxy for flexibility. Subsequently, some other possible objectives for an EPN are considered, illustrating how following one objective will generally produce a result which is suboptimal with respect to another metric. Then methods for multicriteria analysis to consider multiple objectives simultaneously are presented, before concluding remarks on energy positivity and flexibility in districts are given.

Trading wind power in the UK using an imbalance penalty reduction strategy

In the UK, power is mainly traded in a forward market that penalises parties that introduce imbalances to the system at delivery time. This is disadvantageous for wind generators that have to trade power at least one hour in advance (gate closure) based on imperfect forecasts. As a result, wind generators are driven to trade power based on strategies to minimise imbalance penalties. The use of such strategies can increase profits for wind generators, and encourage the construction of wind power projects (WPPs) with higher generation capacities. This paper studies the impacts of a trading strategy on the profits and optimal design of WPPs in the UK considering different levels of wind penetration and demand response (DR) in the system. The results suggest that the use of a trading strategy leads to increased profits for wind generators, especially in adverse market scenarios where the price of wind energy is low, and it can affect the optimal design of new WPPs.