Levelised cost of PV integration for distribution networks

High and continuously increasing photovoltaic (PV) penetration in distribution network introduces many potential power system problems. One of the most important, and often the first to arise, is overvoltage issue. Although many measures have been proposed and implemented to solve the problem, a standardised metric to assess their economic viability is lacking. This paper introduces a PV levelised cost of integration (LCI) metric, which consists of all the capital and operational expenditures incurred when implementing the measures divided by the PV energy generated throughout its lifetime. The measures analysed are active power curtailment (APC), reactive power control (RPC), active-reactive power control (ARPC), as well as various battery energy storage (BES) measures. These measures were simulated on 69-bus and 119-bus distribution networks with real weather and electricity price data. Among the pertinent results are: (1) ARPC is the most cost-effective voltage mitigation measure, followed closely by RPC and APC, (2) BES cost needs to decrease by more than 80% for BES to be economically viable for overvoltage mitigation, and (3) change in reactive power charge, line losses, and BES roundtrip efficiency losses are all important components of LCI and need to be considered in assessing PV integration measures. The results and the LCI framework presented in this study can be used by policy makers, regulators, and researchers to evaluate renewable energy integration policies, methods, and algorithms.