Reshaping roles and value logics among distributed system operators for future electricity systems

In line with the Swedish target of carbon neutrality by 2045, the municipality of Växjö in Kronoberg County has set its own target to be carbon neutral in 2030. Currently, the Municipality's partially decentralized energy system relies heavily on interconnected electricity supply from the national grid, and fuels imports from other parts of Sweden. Under this circumstance, several concerns arise, including: in which ways future demand changes induce supply changes, and whether a future carbon-neutral energy system will be less costly in a sustained-electricity supply condition. In this study, techno-economic evaluations are conducted for different carbon-neutral scenarios for Växjö’s future energy system in 2030 and 2050, using an hour-by-hour dynamic energy simulation tool of EnergyPLAN. Projections for the future energy demands for Växjö were developed and modeled, based on the development strategies and on the national sustainable future scenarios in Sweden. Results for the Växjö’s carbon-neutral scenarios showed that the current energy system is sufficient to satisfy future heat demand. However, fulfilling demands of electricity for all sectors and fuels for transport and industry is a challenge. In the short term and at increased energy demand and price, being carbon neutral is technically viable without major changes in energy supply technologies. However, in the long term, investment for intermittent renewable energy resources, together with carbon capture and storage is considered to be viable financially. Therefore, planning for a carbon-neutral Växjö based on local investments showed to be a feasible strategy.

Introduction: To date, a variety of studies have been published on the topic of long term energy system transition. Most studies on future energy systems, however, have a shorter time frame or adopt a supranational focus (e.g. the Energy Roadmap, 2011 or the World Energy Outlook, 2015). It then constitutes a sincere challenge to perform a national energy system transition study with as time horizon 2050 and covering a far-reaching transformation of the energy system. VITO, together with the FPB (Federal Planning Bureau) and ICEDD, performed a study to scrutinise the transition of the Belgian national energy system towards a future mix entirely based on renewable energy sources. The focus on renewable energy sources and on building a national energy system completely running on renewable energy can be traced back to three main concerns: – Climate change: Renewable energy sources (RES) are a major instrument in the fight against climate change as RES do not release (net) greenhouse gas emissions. – Security...

Future highly renewable energy systems will couple to complex weather and climate dynamics. This coupling is generally not captured in detail by the open models developed in the power and energy system communities, where such open models exist. To enable modeling such a future energy system, we describe a dedicated large-scale dataset for a renewable electric power system. The dataset combines a transmission network model, as well as information for generation and demand. Generation includes conventional generators with their technical and economic characteristics, as well as weather-driven forecasts and corresponding realizations for renewable energy generation for a period of 3 years. These may be scaled according to the envisioned degrees of renewable penetration in a future European energy system. The spatial coverage, completeness and resolution of this dataset, open the door to the evaluation, scaling analysis and replicability check of a wealth of proposals in, e.g., market design, network actor coordination and forecasting of renewable power generation.

Most analyses of the future European energy system conclude that in order to achieve energy and climate change policy goals it will be necessary to ramp up the use of renewable energy sources. The stochastic nature of those energies, together with other sources of shortand long-term uncertainty, already have significant impacts in current energy systems operation and planning, and it is expected that future energy systems will be forced to become increasingly flexible in order to cope with these challenges. Therefore, policy makers need to consider issues such as the effects of intermittent energy sources on the reliability and adequacy of the energy system, the impacts of rules governing the curtailment or storage of energy, or how much backup dispatchable capacity may be required to guarantee that energy demand is safely met. Many of these questions are typically addressed by detailed models of the electric power sector with a high level of technological and temporal resolution. This report describes one of such models developed by the JRC's Institute for Energy and Transport: Dispa-SET 2.0, a unit commitment and dispatch model of the European power system aimed at representing with a high level of detail the short-term operation of large-scale power systems. The new model is an updated version of Dispa-SET 1.0, in use at the JRC since 2009. Table of

An evaluation framework for future integrated energy systems: A whole energy systems approach

This paper discusses and identifies the effect of Distributed Generation (DG) units on delivery loss reduction and efficiency improvement of future electric systems. It demonstrates that optimal placement and utilization of DGs in distribution feeders and radial distribution networks can lead to significant efficiency improvement through different parts of electric power systems. To this end, Utilities and Distribution System Operators (DSO) need to encourage DG owners to participate in optimization process. This can be done by implementing encouragement mechanisms such as price signal or feed-in tariffs. Furthermore, this paper investigates and optimizes the effect of μ-level DG units on delivery loss reduction and efficiency improvement of distribution feeders. The paper also proposes two major optimization algorithms for optimum placement and utilization of medium-size and MW-scale DGs in LV distribution networks. Finally, the paper closes with a discussion of policies needed to support efficiency improvement and delivery loss minimization of future distribution systems with large penetration of DG units.

In nowadays Smart Grids, economic optimizations performed by Virtual Power Plants (VPPs) may interfere with stable grid operation required by Distribution System Operators (DSOs). Since Smart Grids and VPPs are important building blocks of future energy systems, bridging the gap between economic optimization performed by VPPs and stable grid operation required by DSOs is an important task. In this paper, we present a fundamental system architecture and a concept enabling VPPs and DSOs to negotiate their positions to satisfy the needs and requirements of both sides. Thus, instead of being a potential interference factor, economically sensible operation of distributed energy resources (DERs) organized in VPPs and stable grid operation as required by DSOs are integrated in a common solution.

PrefaceThe 2nd International Conference on New Energy and Future Energy System (NEFES2017) was held from September 22nd to 25th, 2017 in Kunming, China. The technical program comprised three keynote speakers, fifty invited speakers, five oral presentation sessions and an interesting poster session.NEFES 2017 is sponsored by Yunnan Normal University. It aims to provide a platform for researchers and practitioners in both industry and academia to have a brainstorm, share their latest achievements and discuss the possible challenges in terms of new energy and future energy system. This volume records the proceedings of NEFES 2017 and contains 81 rigorously selected manuscripts submitted to the NEFES 2017 conference. All the manuscripts were selected depending on their quality and relevance to the conference.The Organizing Committee would like to thank all the authors who contributed to NEFES 2017 and also the reviewers who provided their valuable comments and suggestions.The 3rd International Conference on New Energy and Future Energy System (NEFES 2018) will be held in Shanghai, China. Everybody is welcomed to submit high quality papers to NEFES 2018! More information will be available at the conference website: http://www.intergridconf.org/2018/EditorDr. Grigorios L. KyriakopoulosNational Technical University of Athens, Greece.

IEA EBC Annex 67 Energy Flexible Buildings

Pakistan is currently undertaking a substantial expansion of electricity generation capacity to provide electricity for all its end‐users and to satisfy a fast‐growing economy. Adoption of low‐cost, abundant and clean renewable energy will not only fulfil its growing electricity, heat, transportation and desalinated water demand but also help achieve the goals set under the Paris Agreement. A technology‐rich energy system model applied in hourly resolution has been used for investigating the transition in 5‐year periods until 2050. This study demonstrates that a 100% renewable energy system across the power, heat, transport and desalination sectors is not only technically feasible but also economically viable. Solar photovoltaics emerges as a key technology to generate electricity and contribute a share of 92% to the total primary energy demand across all sectors by 2050. The levelised cost of energy for a 100% renewable energy system is calculated as 56.1 €/MWh in 2050, lower than 70 €/MWh for the current fossil fuel‐based system. A key feature of Pakistan's future energy system is the huge increase in demand across all energy sectors, particularly for desalinated water, which is almost 19% of the final energy demand. This share of energy for desalination is among the highest in the world. Direct and indirect electrification across all demand sectors increases the efficiency of the future energy system. Moreover, GHG emissions from all the sectors will drop to zero by 2050 in a fully sustainable energy scenario.

The directions for the transformation of the key hierarchically-structured infrastructure energy systems, i.e., electric power, heating, and gas supply systems, as influenced by intensively expanding adoption of technology innovations in physical (power) and information-and-communication subsystems are studied. The peculiarities of the transformation of the energy systems structure at their different hierarchical levels are analyzed. Changes in the properties of future energy systems as influenced by innovation-driven processes and facilities are discussed. Interpretations of new properties of transforming energy systems, i.e. flexibility and resiliency, which have recently been the subject of much research effort are analyzed. It is argued that in the future the above energy systems will acquire the features of integrated cyber-physical systems. The fundamental role of developing control systems for future infrastructure cyber-physical energy systems is emphasized.

Future energy systems will come with a 100% share of renewable energy and high integration of energy systems. District heating and cooling systems will be undeniable parts of the future energy systems, as they pave the bed for high-efficiency, low cost, and clean production. District heating systems may come into a wide range of designs in the future. Currently, most of the world’s district heating systems are based on the third generation design while everything in this framework is on the verge of a transition to the fourth generation. A large number of technologies for the future district heating systems has been proposed so far, among which low-, ultralow- and variable-temperature systems seem more of qualification. This study employs computational fluid dynamics to make a comprehensive examination of the compatibility of regular twin-pipes with various potential district heating schemes for future energy systems. The results show that both low- and ultralow-temperature systems could efficiently use regular twin-pipes commonly used in the third generation district heating systems, though the insulation of the pipe could be proportionally strengthened based on a techno-economic trade-off. In contrast, the results show that the thermal inertia of the pipe does not allow the variable-temperature district heating system to effectively operate when the transmission pipeline is longer than a limited length. Therefore, a regular heat distribution network may not be an appropriate host for a variable-temperature district heating scheme unless decentralized heat production units come into service.

In this paper we study dynamical distortion problems in future electrical energy systems with high renewable penetration. We introduce a new time-domain modeling of electrical energy systems comprising inverter-controlled distributed energy resources (DERs). This modeling is first used to quantify the relations between distortions and real/reactive power dynamics. Next, to ensure acceptable Quality of Service (QoS), a novel nonlinear distributed inverter control is introduced. Sufficient conditions are established for the guaranteed performance of the proposed control. These conditions further support the practical implementation of the derived controller. The effectiveness of this enhanced control is illustrated using simulations for the case of avoiding system instability during sudden grid reconfigurations. Simulations also show that distortions can be suppressed in systems with parallel-connected solar photovoltaics (PVs).

Conceptual model of the industry sector in an energy system model: A case study for Denmark

Post COVID-19 ENERGY sustainability and carbon emissions neutrality