Forecasts for strong El Niño conditions this winter, triggered by unusually warm seas, are causing Californians to brace for drenching rainstorms, mudslides and other havoc. A less anticipated El Niño effect may be a sharp increase in the demand for natural gas.

The cloudy and rainy weather expected this winter in much of the state will reduce the output of solar panels used by homeowners, businesses and utilities to generate electricity. That will require a significant increase in the use of natural gas in power plants to make up the difference.

Demand for electric power peaks in morning and evening hours as households get ready for and return from work, school and other daily activities. To meet these peaks, utilities bring gas-fueled generators online to supplement their baseline generating capacity.

About 7% of California’s baseline capacity is solar generation, with utility-operated solar plants providing almost 7,000 megawatts of electrical power, and about 3,000 megawatts of power coming from panels on the roofs of homes and businesses.

During winter months, sundown comes several hours earlier than during the summer, so solar power isn’t available to meet the early-evening needs of residents. With the cloudy weather expected as a result of El Niño conditions, solar output will be reduced earlier in the day.

There’s plenty of natural gas available to fuel generating plants, thanks to hydraulic fracturing and other advanced production techniques. Even with fewer drilling rigs working and increased exports, gas supplies are abundant, according to the Federal Energy Regulatory Commission’s most recent Energy Market Assessment.

However, transportation bottlenecks could impact the ability of utilities to meet peak loads. The Commission noted that in the winter of 2013-2014, Southern California Gas Co. “encountered problems serving generator natural gas demand” because the volume of gas utilities were using reduced the pressure in its pipelines.