| dc.description.abstract | Injections to and withdrawals from the electricity grid should continuously be in balance to
avoid large deviations from the reference grid frequency. In case of grid imbalance,
transmission system operators (TSOs) activate balancing reserves to correct the imbalance.
With increasing variable renewable generation, different model studies expect that balancing
reserve capacity should increase to cover the larger forecast errors of variable renewable
generation. However, different studies identified that balancing reserve capacity has
decreased in the past, while variable renewable generation has increased. The goal of this
study was 1) to provide an overview of developments in the Dutch and German balancing
markets 2) study the relationship between different possible contributors, including variable
renewable generation, and system imbalance, using 15-minute data between 2015 and 2017
for the Netherlands and Germany.
The results showed that in both the Netherlands and Germany the penalty for being in
imbalance has decreased over time. Imbalance volumes increased in the Netherlands, but
stayed relatively constant in Germany. Market design seemed to have a major impact on
these developments. Regression analyses were performed to study the relationship between
variable renewable generation, total generation, total load, and the forecast errors of these
factors on the one hand and system imbalance on the other hand. All regression analyses
followed the expected trends (e.g. higher system imbalance with higher variable renewable
generation), but the correlation values were weak. This indicated that the impact of variable
renewable generation on imbalance volumes is limited | |
