There’s no doubt about it: California’s decade-long efforts to expand the use of solar, wind, and other renewable energy and improve energy efficiency have enabled the state to significantly reduce its consumption of natural gas for power generation. But the Golden State’s rapid shift to a greener, lower-carbon electricity sector — and its push to shut down gas-fired power plants — has come at a cost, namely an increased risk of rolling blackouts, especially during extended heat waves in the West when neighboring states have less “surplus” electricity to send California’s way. The main problem is that while solar facilities provide a big share of the state’s midday power needs, there’s sometimes barely enough capacity from gas plants and other conventional generation sources to take up the slack when the sun sinks in the late afternoon and early evening. Today, we discuss recent developments on the power front in the most populous state, and what they mean for natural gas consumption there.
The biggest news out of California these days, of course, is the wildfires that have devastated parts of the state and blanketed much of the region in an eerie orange haze. And there’s COVID-19 — no small matter. As if these weren’t enough, another leading concern of state officials, businesses, and individuals alike is the heightened potential for power interruptions. In the midst of a prolonged heat wave last month, the state’s electric grid operator, faced with sky-high power demand and insufficient power supply, ordered rolling blackouts for the first time since 2001. The impacts may not seem huge from the outside looking in — a few hundred thousand customers without electricity for an hour or two at a time — but tell that to the manager of an affected factory, Home Depot, or supermarket, or to parents wanting to prepare dinner on an electric range in their normally air-conditioned home when it’s 104° outside. More importantly, the rolling blackouts confirmed the fears of many that California’s plan to de-carbonize the power sector, while well-intentioned, may be too aggressive and may fail to adequately ensure grid reliability.
As shown in Figure 1, California’s electric utilities, independent power companies, and other power generators have reduced their consumption of natural gas by leaps and bounds over the past eight years as the state ratcheted up its efforts on energy efficiency and renewables. The state’s “power burn” — i.e., gas consumed by combined-cycle, peaking, and cogeneration plants to produce electricity — varies by season and by year, mostly due to weather and air-conditioning needs, but average gas consumption by the electric sector has been declining steadily. Since 2012, when California’s power burn averaged 2.34 Bcf/d in 2012 (blue bar to far left), the electric sector’s gas consumption there has fallen by more than one-third, averaging 1.58 Bcf/d in 2019 and 1.28 Bcf/d in the first half of 2020 (blue bar to far right).
Figure 1. California Gas Consumption for Power Generation. Source: Energy Information Administration
The decline in California’s power burn is tied primarily to the state’s efforts to reduce greenhouse gas emissions by the power sector via a renewable portfolio standard (RPS), which requires that increasing percentages of retail electricity sales come from solar facilities, wind turbines, biomass-fired plants, geothermal operations, small hydroelectric plants, and energy storage facilities. The state’s first RPS was enacted in 2002; it called for 20% of electricity to come from renewables by 2017. In 2015, California upped the ante, mandating that renewables provide at least 33% of the state’s power by 2020 and 50% by 2030; that law also called for the state to significantly ramp up its energy-efficiency programs to help electricity and natural gas customers reduce their energy consumption. Then, in 2018, the state enacted a law that increases the 2030 RPS to 60%, and requires that all of the electricity consumed in the state come from carbon-free sources by 2045.
California’s 33% renewables by 2020 mandate has been met, primarily through long-term power-supply contracts between the state’s electric utilities and independent power companies that developed new, large-scale solar facilities and new wind farms over the past several years (blue bars to left in Figure 2). According to the California Independent System Operator (CAISO), which manages the state’s electric grid, nearly 30,000 megawatts (MW) of renewable capacity is currently in operation or will be by the end of this year (first multicolored bar in Figure 2), with solar (yellow bar segments) accounting for more than half of the total. Solar and energy storage (purple bar segments) are expected to account for most of the capacity additions being planned to meet the 60% requirement for 2030.
Figure 2. California’s Existing and Planned Renewable Capacity. Source: CAISO
Solar and wind are different animals than gas-fired generation in that their output varies depending on weather conditions — and, for solar, on the time of day (see our California Sunset series). Gas plants, in contrast, are fully dispatchable; this is, they are always ready to be turned on and dialed up or down as needed. That combination of availability and flexibility is invaluable to power planners, especially in a state like California that has significantly increased the role of variable-output renewables. The problem is that in recent years a number of older, less efficient gas-fired power plants have been retired, and more retirements are planned. That could lead to more situations like the extended heat wave in mid-August, when California’s power grid was left with less gas-fired capacity than it needs to keep pace with demand, requiring the implementation of rolling blackouts on two consecutive days: August 14 and 15.
Figure 3 shows the California grid’s sources of power supply by type and by hour on both days. As you can see, there are five main power sources: natural gas (blue lines), renewables (mostly solar, but some wind; orange lines), “imports” from neighboring states via high-voltage transmission lines (gray lines), large hydroelectric plants (yellow lines), and “other” (green lines) — mostly a steady supply of nuclear power from Pacific Gas & Electric’s two-unit, 2,300-MW Diablo Canyon station.
On Friday, August 14 (left graph), statewide electricity demand was relatively low (~21,000 MW to ~24,000 MW) and was met primarily by a combination of gas-fired plants and power “wired in” from neighboring states, plus some wind and nuclear. The state’s solar power resources — many of them large-scale projects of hundreds of MW each — provided as much as ~13,000 MW, a significant share of the state’s morning and early-afternoon power needs. But as the afternoon heat built up and electricity demand for air conditioning rose, additional gas-fired plants had to come to the rescue. By the time statewide demand peaked at more than 46,000 MW in the early evening, the contribution from solar, wind, and other renewables had declined to ~7,000 MW and gas-fired plants were generating ~26,000 MW, or nearly three-fifths of the state’s power requirements at the time. Generators in other states were providing ~7,000 MW and large-scale hydro facilities ~4,000 MW, with the Diablo Canyon nukes kicking in ~2,000 MW. The unplanned loss of 475 MW of gas-fired power in southern California early that afternoon, combined with rising electricity demand the next few hours, spurred CAISO to declare a rare Stage 3 Emergency — and start implementing rolling blackouts of about 500 MW each — around dinnertime. The crisis eased overnight, but repeated itself the next day (right graph), following very much the same pattern, including the unexpected loss of 1,000 MW of wind power and a 470-MW gas plant, a dinnertime declaration of a Stage 3 Emergency, and rolling blackouts.
Figure 3. California Power Supply by Type, August 14 and 15, 2020. Source: CAISO
There are a few things worth pointing out here. One is that while solar facilities clearly make a significant contribution to midday power supply in California, rising demand for electricity for air conditioning during the afternoon hours — especially during a prolonged heat wave — requires a major ramping up of gas-fired generation. Another is that during a broad, regional heat wave, more of the power generated in neighboring states is consumed in those states and therefore less is available to be transmitted to California. The state’s power-supply problems have continued off-and-on since mid-August. CAISO has issued several so-called Flex Alerts calling for electric customers to reduce their power usage, as well as four Stage 2 Emergency declarations to warn customers that power supply had failed to keep pace with rising demand and that power interruptions were possible.
It should come as no surprise that the wildfires still engulfing swaths of the state are only making things worse. Smoke and dust from the fires has been reducing the electric output of solar panels, both by limiting the amount of sunlight that can reach them and by coating solar panels with dust and thereby hindering their efficiency. Also, some high-voltage transmission lines have been taken offline to minimize the possibility that they might start wildfires, and still others have been damaged by the fires.
Even as the wildfires continue to burn, the debate about California’s RPS and the future of gas-fired plants there rages on. Environmental interests argue that the state needs to accelerate — not slow down — efforts to reduce its carbon-dioxide (CO2) emissions, perhaps by requiring that all of the state’s electricity come from carbon-free sources by 2030, not 2045. However, many power planners are urging a more cautious approach under which more gas-fired capacity would be kept online longer. Earlier this month, the California State Water Resources Control Board agreed to extend the deadline for nine older gas-fired units (combined capacity 3,700 MW) to comply with a rule on reducing their water use for plant cooling. Without the extension, the plants would have been forced to retire by the end of this year; with the water board’s September 1 action, three units with 830 MW of capacity can remain in operation through December 2021, and six units with 2,870 MW will be available through the end of 2023. By then, California not only will have added considerably more solar and other renewable capacity, it will have brought online more energy storage facilities that can be used to provide supplemental power as solar output ramps down each afternoon.
"California Dreamin'" was written by John and Michelle Phillips, and it appears as the first song on side two of The Mamas & The Papas’ debut studio album, If You Can Believe Your Eyes and Ears. A little-known fact about this song is that it was originally recorded and released by Barry McGuire, with The Mamas & The Papas singing backing vocals on it. After it failed to become a hit, producer Lou Adler, who worked with McGuire and The Mamas & The Papas, erased McGuire's vocals on the recording and added The Mamas & The Papas’ Denny Doherty singing the lead. After adding a guitar intro and alto flute solo, Adler re-released the song as a Mamas & Papas single in December 1965. If you listen closely to the song in headphones, on the left side, you can hear a snippet of McGuire's original lead vocal as the song begins. It went to #4 on the Billboard Hot 100 Singles chart and has been certified Gold by the Recording Industry Association of America (RIAA). The song was inducted into the Grammy Hall of Fame in 2001. Many artists have covered the song since its initial release. Personnel on the record were: Denny Doherty (lead vocals), John Phillips (backing vocals), Michelle Phillips (backing vocals), Cass Elliot (backing vocals), P.F. Sloan (guitar), Joe Osborn (bass), Hal Blaine (drums), Larry Knechtel (keyboards), Peter Pilafian (electric violin), and Bud Shank (alto flute).
If You Can Believe Your Eyes and Ears was recorded at Western Studios in Hollywood in late 1965 and early 1966. Produced by Lou Adler, the album was released in February 1966 and went to #1 on the Billboard Top 200 Albums chart. Four singles were released from the LP, which has been certified Platinum by the RIAA.
The Mamas & The Papas were an American folk rock vocal group formed in Los Angeles in 1965. They have sold more than 40 million records worldwide and have released five studio albums and 17 singles — six of the singles made the Top 10. The Mamas & The Papas are members of the Rock and Roll Hall of Fame and the Vocal Group Hall of Fame. The band officially broke up in 1969, with all four members going on to solo careers. Cass Elliot died in 1974, John Phillips in 2001, and Denny Doherty in 2007. Michele Phillips has continued to have a successful career as an actress.
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