Mark Z. Jacobson
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mzjacobson.bsky.social
Mark Z. Jacobson
@mzjacobson.bsky.social

Climate, pollution, clean/renewable energy
Stanford U Prof, Civil & Env Eng; Director, Atmos/Energy Program
Cofounder-Solutions Project; Appeared on Letterman
Testified Held v Montana

https://web.stanford.edu/group/efmh/jacobson/
Stanford.io/Jacobson .. more

Mark Zachary Jacobson is a professor of civil and environmental engineering at Stanford University and director of its Atmosphere/Energy Program. He is also a co-founder of the non-profit, Solutions Project. .. more

Environmental science 27%
Public Health 16%

This is a plot of the raw data from CAISO. You need to download the data every day and sum it up in a spreadsheet

www.caiso.com/todays-outlook
Today's Outlook | Demand | California ISO
Monitor real-time grid conditions. View current and historical data for demand, net-demand, supply, renewables, CO2 emissions and wholesale energy prices.
www.caiso.com

California grid electricity demand continues to decline despite 2.5 million EVs and lots of data centers in the state

2026 Demand on CAISO grid down 1.84% v '25; 1.22% v '24; and 2.27% v '23

Due to growth in behind-the-meter roof PV, which eliminates need for grid electricity

Close to the same number of heat pumps, but TX has nowhere near the number of roof PV units or insulation standards or appliance standards, and those exist in homes without heat pumps in CA.

Also, CA has 2.5 million EVs vs only 400,000 in TX so more electricity demand there.

Reposted by Nancy­ Knowlton­

This state’s power prices are plummeting as it nears 100% renewables

"South Australia is proving to the world that relying largely on wind+solar energy with battery back-up is incredibly cheap, with electricity prices tumbling by 30% in a year..."

www.newscientist.com/article/2514...
This state’s power prices are plummeting as it nears 100% renewables
South Australia is proving to the world that relying largely on wind and solar energy with battery back-up is incredibly cheap, with electricity prices tumbling by 30 per cent in a year and sometimes ...
www.newscientist.com

This has been known since the 1980s:

"CA's mandatory building and appliance efficiency standards... Electricity demand is growing much more slowly in California than in Texas where almost no energy-efficiency standards have been imposed."

www.researchgate.net/publication/...
(PDF) Managed versus unmanaged 7-year electric growth: Californian's needed 3 new plants, Texans needed 11
PDF | California's mandatory building and appliance efficiency standards, aided by a few billion dollars of utility conservation programs, have greatly... | Find, read and cite all the research you ne...
www.researchgate.net

Temperature is only relevant if the homes are the same. But, even when the temperature outside is 106 F in CA, a well-insulated home with PV, heat pumps & efficient appliances uses 0 grid electricity and sends excess PV to the grid

Far fewer homes in TX have these features, so TX wastes far more
Despite CA having 2x the electricity price as TX, Texans pay 28% more per capita for electricity yearly because TX uses 2.7x the elec per capita as CA (vs 2.1x in 2001, so nothing to do with weather) even with 2 mil more EVs in CA than TX

Why? Stronger effic & building standards & more BTM PV in CA

Not so. If we just look at the residential sector with EIA data, TX uses 2.53x the electricity per capita as California (versus 2.66x for all sectors together).

In the industrial sector, the ratio is 5.18x

Data also show that Texans have paid 28-52% higher annual electricity bills than Californian every year for the last 25 y

So, when someone points to CA's high electricity price, explain that what people pay is price x use, and electricity use/person in CA is the lowest in the US
Despite CA having 2x the electricity price as TX, Texans pay 28% more per capita for electricity yearly because TX uses 2.7x the elec per capita as CA (vs 2.1x in 2001, so nothing to do with weather) even with 2 mil more EVs in CA than TX

Why? Stronger effic & building standards & more BTM PV in CA

Despite CA having 2x the electricity price as TX, Texans pay 28% more per capita for electricity yearly because TX uses 2.7x the elec per capita as CA (vs 2.1x in 2001, so nothing to do with weather) even with 2 mil more EVs in CA than TX

Why? Stronger effic & building standards & more BTM PV in CA

Myth-busting alert:

The days are over where gas, coal, or nuclear is needed to keep a small city operating with zero solar or wind

Calistoga, California can operate for 48 hours during a blackout with a 8.5 MW/293 MWh battery-H2-fuel cell system

www.energyvault.com/projects/cal...
Project – Calistoga Resiliency Center
Pioneering battery-hydrogen fuel cell system providing a community microgrid with continuous power for at least 48 hours.
www.energyvault.com

“These plants increase air pollution, they increase global warming...they increase not only energy costs, but total social costs, and so there’s zero benefit — except to the people who are taking the subsidies"

Louisiana bets big on ‘blue ammonia
floodlightnews.org/louisiana-bl...
Louisiana bets big on ‘blue ammonia.’ Communities along Cancer Alley brace for the cost.
Carbon capture hasn’t delivered major climate benefits — and the plants would still emit thousands of tons of pollution.
floodlightnews.org

Reposted by Mark Z. Jacobson

Reposted by Mark Z. Jacobson

Not only does California's 22GW of solar have reliability similar to US coal,

but CA also has 15.8GW/63.2GWh of batteries, which can store 63.2GWh/d of PV and then discharge 3.95GW of flat output for 16h

So PV+batteries can provide ~2x the baseload output of nuclear in CA (2.2GW) for 24 h in a day
CA solar is almost as reliable as coal:

2025 avg capacity factor of all 21.58 GW* of solar on the @California_ISO grid:

30.2%

2024 CF US coal:

42.6%

www.eia.gov/electricity/...

->Coal not much more reliable than CA solar

*=avg Dec '24 & Dec '25 nameplates
Solar output: 57,054 GWh/y
Electric Power Monthly - U.S. Energy Information Administration (EIA)
www.eia.gov

22nd day of 2026, that is.