In recent days California is struggling to contain the large fires that have burned hundreds of thousands of hectares of land and forced the evacuation of an equally large number of people. Due to the high temperatures and the sharp increase in the demand for energy from the population, the California authorities have had to resort to scheduled power outages in an attempt to balance supply and demand.
Several opinion articles have taken inspiration from the situation in California to warn of the risks associated with an energy transition that is too hasty that does not take into account the weaknesses of renewable sources.
12 percent of electricity in the United States is generated from wind and solar energy. Leading the nation is California, which than the rest of the country currently has more ambitious goals in terms of renewables: within the year, 33 percent of California's electricity will have to be generated from renewable sources.
The quota will have to reach 50 per cent by 2030, and then reach the complete decarbonisation of the electricity grid by 2045.
Fires and renewable energy: the California problem
Californian power grid has not proved resilient and reliable.
And it is a problem, because the supply of electricity is a priority for every economy and must be guaranteed at any time and at any time of the year. In California, the demand for electricity is generally highest during the afternoon hours of the summer months, when there is a greater use of air conditioners.
Gas-fired plants are able to respond very effectively, more than coal-fired ones, to sudden peaks in demand because they are able to rapidly increase and decrease their production. The same cannot be said for wind and solar plants, because their output is determined by external factors such as the time of day, the season and the weather conditions.
The increase in the share of renewables in the Californian electricity grid would therefore have made it less flexible and less reliable. Storage is considered the game-changer of the energy transition, as the Los Angeles Times also wrote.
Taking California as a reference, photovoltaic systems produce more electricity during the day than is required; the batteries allow you to store this excess energy, which can be used in times of increased demand or when there is little or no sunshine (during winter, or at night).
Storage thus allows to solve the problem of intermittency of renewable sources. However, the crisis in the Californian electricity grid cannot be attributed exclusively to the greater share of renewables in the energy mix.
Rather, it is the result of the combination of many factors. The record temperatures, first of all: in Death Valley it would have touched 54.4 degrees, the highest figure ever recorded on Earth since 1913. The US government has declared a state of natural disaster for the situation in California.