Enhancing the self‐resilience of high‐ renewable energy sources, interconnected islanding areas through innovative energy production, storage, and management technologies: Grid simulations and energy assessment

Abstract

Electrification of heating and transportation can be greatly combined with excess energy production from variable renewable energy sources that exist in many geographical islands. Grid interconnections, where available, play a vital role in the energy system as provide the required balance between energy consumption and demand but many limitations emerge due to cable capacity and other technical constraints, which in many cases, lead to curtailment events. With the minimization of the energy exchange through the cable between islands and the mainland, the islands' self-resilience is enhanced. The islands of Samsø and Orkney are used as the case studies where, among others, the specific technical solutions of (a) heat pump districting heating with heat storage, (b) electrolyzer for hydrogen production, and (c) electrical vehicles are examined. The proposed technical solutions are enhanced by Demand Side Management actions utilizing high renewable energy sources availability and curtailment events. The solutions are examined and compared with a reference/current status scenario for each island. This work is based on a detailed model representation, using Modelica language, of the transfer and distribution grid assets, allowing the estimation of the impact of the proposed electrification solutions to the grid level as well as the island level. Simulation results revealed that with the proposed actions in Orkney, annual energy export is reduced by 24 GWh but the corresponding energy imports are slightly increased by 13 GWh, reducing curtailment by 1.4 GWh (77%). As for Samsø, the energy imports are reduced by 5 GWh, while the energy imports increase by 2.0 GWh. Grid losses remain at the same level as before at around 2%, but some distribution lines have significantly lower energy traffic due to higher renewables self-consumption.

State Estimation in Unbalanced Smart Grids

“…In particular, (2) ensures that in each phase, ϕ, the total amount of injected active power at node i, P ϕ gi , is equal to the node's total active power demand, P ϕ ci , and the total active power flow exiting the node, P ϕ i . The same rule applies for reactive power, as presented in (3), where Q ϕ gi is the total amount of injected reactive power at node i, Q ϕ ci is the total reactive power demand at node i and Q ϕ i is the total reactive power flow exiting the node i . Furthermore, the voltage magnitude of each node, i, in each phase, ϕ, V ϕ i , is limited by (4), where V ϕ min,i and V ϕ max,i constitute the lower and upper boundaries, respectively.…”

“…The ever-growing "green" transformation of the global energy systems is directly correlated with the smart grid concept, which essentially embodies a series of features such as optimal Renewable Energy Sources (RES) integration, optimised energy management, remote real-time monitoring and control, etc. [1]- [3]. In order to achieve the aforementioned capabilities, it is important to assess the state of the smart grid, which requires the acquisition of measurements provided by sensors.…”

Day Ahead Optimal Dispatch Schedule in a Smart Grid Containing Distributed Energy Resources and Electric Vehicles

“…EV i max , is taken into account in (8). It is noted that u EV i ch t is the binary variable that indicates whether the i-th EV is being charged at time-step t or not.…”

“…Toward that end, the adoption of renewable energy sources (RES) such as photovoltaic panels (PV) and wind turbines (WT), as well as battery energy storage systems (BESS) and other energy storage systems (ESS), is ever increasing [3][4][5]. Another recent trend is the procurement of electric vehicles (EVs) by public and private entities alike [6][7][8]. The importance of the mass use of EVs is paramount as they reduce greenhouse gas emissions compared to conventional vehicles using fossil fuels [9].…”

Power Flow Analysis in Unbalanced Distribution Networks Considering High Photovoltaic Production

“…Distribution networks constitute a research field that has gained attention over the past decades due to their potential regarding Distributed Energy Resources (DER) deployment [1]. Especially when it comes to the environmental footprint of the electrical grid, research and development are oriented toward the integration of Renewable Energy Sources (RES) [2], such as Photovoltaic (PV) panels and Wind Generators (WG), which reduce the required fossil fuel production, CO2 emissions and transmission losses [3], [4]. In this sense, special simulation tools have been developed, capable of analyzing the operation of distribution networks with high RES penetration [5].…”