In 2015, energy from grid-connected, utility-scale solar plants surpassed that from wind power for the first time ever in California, according to an analysis from Vaisala.
The environmental and industrial measurement company says California has been a national leader in renewables since first establishing its renewable portfolio standard (RPS) in 2002, and with a 50% RPS recently signed into law, the state is likely to maintain its position for years to come. Today, the state is still one of the largest U.S. wind markets in terms of capacity, but Vaisala says exponential growth of large-scale solar in recent years has considerably altered the structure of the regional energy market.
Vaisala cites public records from the California Independent System Operator (CAISO), which indicate that over the past five years, grid-connected, utility-scale solar generation in California increased fifteen-fold. It went from a total of 1,000 GWh in 2011 to an impressive 15,592 GWh in 2015, composing 6.7% of the system total and surpassing wind for the first time, which made up 5.3% of the system total.
This is an exciting milestone for the solar industry, as high solar market penetration benefits California with lower carbon emissions and lower electricity prices, given that there is no associated fuel cost. However, Vaisala says that as solar capacity has grown, so too has the effect of its variability on the market. As supply rises and falls, system volatility increases, thus influencing prices. In order to minimize price while maximizing clean energy generation, the company says it is essential that the market is able to anticipate these supply swings and respond accordingly.
Vaisala notes it has introduced a new regional forecasting service for the CAISO market to help it adapt to the increased volume of variable solar capacity, and the company claims its CAISO forecast has proven to be consistently more accurate than the day-ahead public forecast.
“California’s continued commitment to renewable energy is very encouraging and creates a great deal of opportunity for the industry,” says Pascal Storck, global manager of energy services at Vaisala. “But, as we’ve seen in many markets around the world, rapid capacity growth also inevitably places strain on regional systems. We are helping customers adapt and respond to market changes profitably and sustainably with a new state-of-the-art solar forecast that has been well received by clients in CAISO.”