Group fairness in power systems computation: Evaluating disparities in grid capacity between households with and without rooftop solar

“Fairness-aware” algorithms are increasingly used to allocate grid capacity in electrical power systems, yet they often overlook existing disparities between household groups, such as those arising from unequal rooftop solar adoption. Through simulations on a stylized low-voltage grid using electricity data from the Netherlands, we apply demographic parity, a group fairness metric, to compare differences in grid access and costs between households with and without rooftop solar. Three objectives are analyzed: minimal intervention, proportional fairness, and min-max fairness. The results indicate that (1) “fairness-aware” allocation does not eliminate group disparities, (2) voltage violations influence the distribution of burdens and benefits, (3) lower curtailment compensation can reduce disparities between households, and (4) common fairness evaluation metrics do not capture these group disparities. This study advances the discussion on fairness in power systems computation by encouraging further research on how to avoid reinforcing existing disparities.