California’s electricity duck curve is deepening – pv magazine International

July 6, 2023 Ryan Kennedy

From pv journal USA

The phenomenon of “duck curve” is an electrical grid operation idea which means the mismatch between peak photo voltaic era (midday to afternoon) and peak electrical energy demand (once more within the afternoon and night). Formed just like the define of a duck, the curve exhibits its peaks and valleys that do not coincide all through the typical day.

The expertise of a duck curve could cause stress on the grid and challenges for the electrical energy market, inflicting California and different solar-friendly states to extend the adoption of vitality storage to deal with this. challenges.

The Vitality Info Administration (EIA) shared that as photo voltaic adoption grows in California, the “duck curve” is deepening. The noon peak web load is reducing, making it tougher for the California Unbiased System Operator (CAISO) to stability the grid.

The change in demand for electrical energy from standard energy crops from midday to nighttime, when vitality demand remains to be excessive however photo voltaic era falls, signifies that standard energy crops like pure gas-fired peaker crops must quickly ramp up electrical energy manufacturing to fulfill demand. . That speedy ramp up makes it troublesome for grid operators to match grid provide with grid demand in actual time, a mechanism that balances the grid each bodily and within the wholesale market.

As well as, if extra solar energy is produced than used, operators might must curtail, or deliberately shut down, photo voltaic belongings to keep away from overgeneration. The California Unbiased System Operator (CAISO) diminished 1.5 million MWh of utility-scale photo voltaic in 2020, representing 5% of complete manufacturing, in response to the EIA. Photo voltaic is probably the most dominant supply of vitality topic to discount within the state. The EIA mentioned that 94% of energy curtailments in 2020 contain photo voltaic vitality.

Curtailments peak within the spring months, when demand is comparatively low and photo voltaic output comparatively excessive. For instance, throughout the early afternoon hours of March 2021, a mean of 15% of utility-scale photo voltaic was curtailed, CAISO knowledge reported by the Division of Vitality exhibits.

The EIA additionally warned that the duck curve state of affairs additionally challenges conventional, dispatchable vitality sources by making them uneconomical to function across the clock. This harm to a given facility’s income might result in a retirement of the power and not using a viable alternative, the EIA mentioned.

“Much less dispatchable electrical energy makes it troublesome for grid managers to stability electrical energy provide and demand in a system with massive fluctuations in web demand,” the EIA mentioned.

Nonetheless, the duck curve opens the door for vitality storage to fulfill the grid balancing wants of California and different renewables-based economies.

“The massive-scale deployment of vitality storage programs, comparable to batteries, permits among the photo voltaic vitality generated throughout the day to be saved and saved for later, after sundown,” the EIA mentioned. “Storing some photo voltaic era throughout the day slows down the duck curve, and sending the saved photo voltaic era at night time shortens the duck’s neck.”

Battery vitality storage in California has grown quickly from 200 MW in 2018 to almost 5 GW at present. Operators are planning one other 4.5 GW of storage capability within the state by the tip of the 12 months in response to EIA knowledge, suggesting the solar-plus-battery increase is simply getting began.

Regardless of larger total venture prices, solar-plus-storage has an acquisition worth benefit, says world danger assurance firm DNV. Vegetation with storage can cost their batteries when there’s loads of daylight throughout the day and promote the saved electrical energy when costs are excessive. DNV says that by 2038, the associated fee benefit of photo voltaic and storage co-located initiatives will exceed the associated fee drawback, making these initiatives extra engaging.

“PV and storage programs are designed as a ‘package deal’ to provide vitality on demand, comparable to hydropower, nuclear, or combustion energy crops,” DNV mentioned.

In 10 years, DNV mentioned that nearly 20% of photo voltaic initiatives worldwide might be constructed with devoted storage, and by the center of the century such initiatives will attain about 50%.