On March 11th 2017,
the state of California was able to break an energy-provision record, where renewable energy accounted for more than 55% of power flowing through the grid for three hours. Almost 40% of the electricity flowing across the grid came from large-scale solar power plants (Associated Press, April 11th 2017), consisting of utility-scale solar photovoltaic farms, solar thermal plants, and the panels installed on private homes (Cassie Werber, April 8th, 2017). With the contribution of electricity generated by wind farms, geothermal plants, biomass plants and small hydroelectric dams, renewable sources accounted for over half of all renewable energy demand, during the middle of the day.
It will undoubtedly happen again as the state advances toward its goal of getting half of all its electricity from renewable sources by 2030 (SFGate, April 10th 2017); especially when considering the fact that California has enough big solar facilities to generate up to 9.8 gigawatts of electricity, nearly the output of 10 nuclear reactors. Nonetheless, policy makers and the business have encountered problems, caused by the massive surge in the amount of solar power transferred into power for the grid.
The issue of a “power surge” is an issue being addressed by the California ISO. When there is a surge in solar power, then there is a temporary reduction of reliance on power from plants burning fossil fuels. The power plants take a long time to shut down when not needed, and also take a long time to start back up again when the sun has set, so usually they continue producing; this also saves operating costs of restarting the system. This raises questions about their efficiency in contemporary times.
Some power plants make the choice to continue producing electricity anyway, and in a very bizarre snapshot of events, end up paying utilities to accept their energy. This lack of efficiency is often translated into loss of profit. For most people who subscribe to a free-market ideology, this would be enough evidence that the business model is no longer, profitable, sustainable or viable and should not be pursued. Nevertheless, the reality is that the consumer is bearing the cost of industry inefficiency: loss of profit is often transferred to the consumer, who is charged a higher tariff for using energy in the evening, when reliance of fossil fuel energy is greater.
In order to prevent this from happening, surging solar energy is curtailed from the grid, to decrease the burden on current industry, and support “business as usual”.