Going with the wind: temporal characteristics of potential wind curtailment in Ireland in 2020 and opportunities for demand response

Abstract

The Republic of Ireland and Northern Ireland have ambitious targets for 40% of electricity to be supplied by renewables by 2020, with the majority expected to be supplied by wind power. There is, however, already a significant amount of wind power being turned down, or 'curtailed', and this is expected to grow as wind penetrations increase. A model-based approach is taken to estimate curtailment using high-resolution wind speed and demand data covering four years, with a particular focus on the temporal characteristics of curtailment and factors that affect it. The model is validated using actual wind output and curtailment data from 2011. The results for 2020 are consistent with previously published estimates, and indicate curtailment levels ranging from 5.6 to 8.5% depending on assumptions examined in this study. Curtailment is found to occur predominantly at night, and to exhibit stochastic variability related to wind output. To accommodate high penetrations of wind power, the findings highlight the value of flexible demand over relatively long timeperiods. The model's output data have been made publicly available for free for further investigation.

Impact of wind curtailment and storage on the Irish power system 2020 renewable electricity targets: a free open-source electricity system balancing and market (ESBM) model

“…The authors have previously contributed to this literature [15] by estimating potential curtailment on the All-island system with results consistent with those of Mc Garrigle et al This paper builds on this work by estimating the installed wind capacity required to meet the 37% demand target. Furthermore, the paper extends the model to estimate the potential impact of electrical energy storage on reducing curtailment.…”

“…Results Figure 3 shows mean curtailment results with 500 MW of interconnection for the 4 years of data. Whiskers extend to show differences between the results published in the previous paper [15]. The results presented here show higher levels of curtailment for system non-synchronous penetration limits of 50% and 60%, with negligible differences for 75%.…”

“…The model developed for the authors' previous paper [15] consists of a component to estimate aggregated hourly wind output based on hourly wind speed data from 51 grid nodes around the island, and a component to estimate curtailment based on hourly wind power output and demand data and a set of curtailment rules based on the published rules that govern which conventional generators need to be kept on-line for system security reasons.…”

“…The four years of hourly demand data and national wind power capacity factors that were calculated in the previous paper [15] for the years 2009 through to 2012 are re-used here. To estimate 2020 values, the installed wind capacity and demand are scaled up appropriately (17% in the case of the demand).…”

“…In the model, the curtailment required for the two rules are calculated separately, and the actual curtailment in any one time step is taken as the maximum of the two. The rules are fully described in the previous paper [15], while the following focusses on their implementation.…”