Gap analysis of future energy grids

Abstract

Based on existing low and medium voltage grids from distribution system operators and future scenarios of PV and EV penetration, critical load scenarios which lead to violations of relevant KPIs are to be developed in the scope of PlanGridEV. In the course of the gap analysis the expected limits of DER hosting capacities were identified. The method for developing and simulating the different scenarios is following a state-of-the-art approach. Results for each power grid and scenario are addressing specific KPIs. The main goal of this analysis was to assess the current EV and PV hosting capacity of existing low voltage and medium voltage grids and identify the factors which limit this hosting capacity. It is shown that European DSOs share similar structures. Depending on voltage level and topology type, specific KPIs were violated by increasing numbers of RES or EVs. Indications for synergies between PV and EVs could be identified due to an increased hosting capacity in the extra PV scenario.

Review on the PV Hosting Capacity in Distribution Networks

“…The estimated HC values of the rural networks are lower as compared to urban networks pertaining to the topological and electrical properties of the former [63] and due to the voltage rise issues at the end of long weak feeders [38]. HC of 239.7% with reference to the peak load of a Finnish LV balanced urban network for 0% MV change is higher than the HC of 198.1% of balanced rural network despite the similar geographical location of 61.9241° N [28].…”

“…Two urban unbalanced LV networks in Kotte (6.8868 • N) and Perth (31.9505 • S) can accommodate the maximum HC values with respect to transformer rating as 40% and 31.9% in [72] and [39], respectively. The HC values without any mitigation means of three urban networks in the Northern hemisphere are found as 32 MWp, 522 kW and 4.8 MW (77%) in [88], [63] and [10], respectively. In [88], the authors investigated an uncontrolled and controlled PV deployment scenario for an urban network in Phapos, Cyprus (34.7720 • N) under two PF settings of unity and 0.95 and observed that performance indices start violating after 32 MWp.…”

“…The authors of [3,5,9,10,14,24,44,48,[54][55][56][57][58][59][60][61][62][63][64] defined PV HC with reference to the peak load of the feeder as the ratio of the maximum capacity of the PV installation to the maximum load of the feeder. In [65], the authors investigated the HC of a rural European three-phase balanced system for two types of simulations that is one-time slot simulation and time series simulation and an estimated HC of 86% of peak load has been observed.…”

“…In [88], the authors investigated an uncontrolled and controlled PV deployment scenario for an urban network in Phapos, Cyprus (34.7720 • N) under two PF settings of unity and 0.95 and observed that performance indices start violating after 32 MWp. Similarly, [63] discussed the impact of network topology on HC variation by comparing the urban and rural networks in 54.5260 • N with urban networks having higher HC value of 522 kW than 132 kW of rural network in the same geographical area. A fairly low PV penetration of 15-30% of peak load (33.69 MW) is noticed in an Urban balanced three-phase network in New Orleans (29.9511 • N) with distributed PVs [58].…”

“…Furthermore, the three rural networks in the Northern hemisphere recorded the HC values (w.r.t peak load) without any control as 1.2 MW-3.2 MW [3], 86% [65], and 132 kW [63]. In [3], a rural network in Japan (36.2048 • N) was investigated and the base HC value of 1.2 MW without PF control was improved to 2.3 MW and 4 MW by controlling voltage using constant PF and distributed control strategies, respectively.…”