Power system planning and operation for non-stationary temperature futures

Climate non-stationarity, including temperature and heat waves, raises significant challenges for electric power reliability. Power grids are designed to be robust to historical weather patterns, so unpredictability in climate... [ view full abstract ]

Climate non-stationarity, including temperature and heat waves, raises significant challenges for electric power reliability. Power grids are designed to be robust to historical weather patterns, so unpredictability in climate conditions present significant planning challenges for ensuring adequate generation to meet peak demand. This is particularly true in the US Southwest, a region expected to experience significant temperature increases, and that heavily uses electric air conditioning and thermal power generation technologies. Global circulation models (GCMs) project temperature increases as large as 6°C for Maricopa county (Phoenix area) Arizona and Los Angeles county (California). Current US policies plan for weather variance by generally building power generation capacity to meet the 90th percentile, T90, hottest temperature projected peak demand, plus 15%. We assessed how future temperatures affect power demand and planning reserve margins. Under the highest GCM temperature projection scenarios we estimate that local reserve margins will reach 30% less than T90 levels – a 1.5 GW and 5 GW difference for the two counties. We calculated these values by creating engineering physics-based structural equation models that are congruent with historical observations. Paradigm shifts will be needed to plan for climate non-stationarity, that can ensure agility of the complex power system in the balancing of supply and demand.