Distributed generation and security of supply: Assessing the investment deferral

Technology advances together with environmental concerns have paved the way for the increasing integration of distributed generation (DG) seen over recent decades, having an important role in governments´ targets. While several technical challenges are now faced by distribution network operators (DNOs) in order to properly accommodate DG developments, one of the major and well-recognised benefits is the ability of DG to defer future demand-related investments. Here, a more integral approach is presented where also reinforcements required by system security standards (e.g., N-1) are taken into account. This methodology builds on a previous work where the successive elimination method and multistage planning were utilised to quantify the investment deferral brought about by DG. The DG contributions to system security provided by the UK Engineering Recommendation P2/6 are adopted, enabling the methodology to quantify the deferment produced by DG considering both demand growth- and system security-related investments. The method is applied to a UK generic distribution network. Results show that significant economic benefits can be harnessed when strategically incorporating DG at the planning stage.