The article examines how record-low sunshine affected electricity supply and demand in the Tokyo area in September, based on supply-demand results and trends in the wholesale electricity market. It also organizes how fluctuations in solar power output, the operating status of LNG-fired generation and moves to restart nuclear power plants were related.
Sunshine was notably limited in September, and changes in solar radiation are viewed as a core factor in observing trends in electricity supply and demand in the Tokyo area. Supply-demand results appear to have correlated at times with changes in solar power generation, and the decline in output caused by low sunshine may have affected supply-demand stability.
As solar power output declined, the operating status of thermal power generation, mainly LNG-fired, appears to have contributed to balancing supply and demand. Changes in the operating level of thermal power may have been linked to fluctuations in market prices, resulting in short-term changes in supply volumes.
Moves to restart nuclear power plants also affected the supply-demand structure and have attracted the attention of market participants as a factor supporting stable supply. Reports indicate that the timing and scale of restarts affected short-term price fluctuations in the wholesale electricity market in some instances.
In the wholesale electricity market, fluctuations in supply and demand affected by insufficient solar radiation and price movements associated with changes in the generation mix are being observed. Some have pointed out that the seasonality of supply and demand and adjustments to facility operations are reflected in price formation. Continued observation of weather factors and power-generation facility operating conditions is considered necessary to assess future market trends.