Transmission network loading in Europe with high shares of renewables

Abstract

The need for long-distance power transfers in the electricity system is being driven by both deeper market integration and the increasing share of renewables in generation. The best renewables resources are often located far from load centres, while variable renewables, such as wind and solar, benefit from smoothing effects when aggregated over large areas. However, the increased usage of transmission infrastructure raises the question of how the associated costs should be distributed. The authors present here the application of an existing algorithm called marginal participation (MP) which can be used to allocate the power flowing through each network asset (lines and transformers) to particular network users. They consider two new methods to extend the MP algorithm to high voltage direct current lines that operate parallel to alternating current networks. They then apply the allocation algorithm to a future scenario with high renewables penetration in Europe in 2050, developed as part of the Smooth PV project. They see a significant increase in network usage, including a rise in the proportion of cross-border flows. The increase in network usage is driven disproportionately by offshore wind, because of its geographical concentration away from load centres.

Optimal heterogeneity in a simplified highly renewable European electricity system

“…A highly heterogeneous system would therefore require a system for countries to compensate each other for their renewable imbalances. Recent work on the allocation of network flows to users in highly renewable networks [51,52] may provide the basis for an equitable distribution of such costs in a highly heterogeneous system.…”

Flow tracing as a tool set for the analysis of networked large-scale renewable electricity systems

“…From a technical point of view, it will be interesting to transfer the idea of more general in-partitions to alternative methods of flow allocation [7,24,35]. First steps in this direction have been taken by [9] for allocation methods based on power transfer distribution factors, but a rigorous discussion is still lacking in the literature. In the present paper we focus on illustrating the versatility of the reformulated flow tracing method by considering a well-defined and fully open benchmark system.…”

“…In this article we present a reformulation of a well-known method of flow allocation, denoted as average participation or flow tracing, that is well adapted to the challenges of the system analysis of complex modern electricity systems. Different approaches to the problem of flow allocation in power grids are often derived from circuit theory [6,7] or are based on approximations of the complex power flow equations for AC electrical networks [8,9]. For the application of such methods to the problem of flow allocation in large-scale models of electricity systems, one has to factor in the potentially coarse-grained nature of such models.…”

The smoothing effect for renewable resources in an Afro-Eurasian power grid

“…Instead, power systems, which rely on renewable generation sources, need additional balancing means. Possibilities include backup, storage (Weitemeyer et al, 2016;Pleßmann, 2014;Heide et al, 2011) or reinforced transmission grid (Brown, 2014).…”