CAISO CEO Steve Berberich directly attributed a 3-5% reduction in load to the stay-at-home order. Lack of demand in office buildings, hotels, and retail spaces (malls) is creating this significant drop. In looking at the CAISO figures as they compared to those from this same time last year, the weekend load saw a drop of roughly 200 megawatt-hours (MWh). However, the weekday load dropped more than 1,400 MWh.

Looking at the supply side, large hydropower is down significantly. In comparing weekdays, large hydro is off by roughly 2,800 MWh. The drop is likely due to the dry start to the 2020 rain season. Unless there is a significant change in California’s weather patterns, these figures are a precursor for our large hydro output this summer.

To make up for the loss of large hydro, other forms of power are needed to ensure reliability. During the weekdays, renewables and imports are up slightly, with less than 200MWh each. Nuclear and coal power, as well as battery storage, remain constant. However, energy from natural gas has increased during the stay-at-home order. In fact, natural gas power is up by roughly 1,400 MWh.

If the COVID-19 lockdown continues as the weather begins to warm over the next month, how will demand be impacted, and how will solar generation in the middle of the day and the “duck curve” be affected? What about the complexity of managing the system? These are questions that remain to be answered. For now, demand is down due to the stay-at-home order, and other energy sources are needed to supplant the decreased supply from large hydropower.