So, there's a really stupid item coming up in Berkeley whereby a bunch of folks who consider themselves climate activists are defending solar panels against the scourge of shadows from tall homes/apartments.

As a solar homeowner, it always seemed bogus to me. So, I did math. 🧵
(First, context: Folks who suddenly care so much about climate change/solar panels are very same folks who actively oppose addressing the number one source of climate pollution in Berkeley -- cars, which cause 60% of our carbon emissions. Related: They're also die-hard NIMBYs)
Anyway, the math.

My house in Berkeley has solar panels that generate ~ 6.3 megawatt hours (MWh) of clean power per year. But that's a) more power than I use per year, and b) largely generated when I don't need it. So, I still buy ~ 2.8 MWh from PG&E; they buy ~ 3 MWh from me.
The carbon emissions of PG&E's electricity are about 206 pounds per MWh. So, my electricity use causes about 556 pounds of CO2 per year. I am deeply ashamed of this.

BUT batteries are still expensive, so, my declaration of a zero emissions house is still in future.

As I said, top source of carbon pollution in California is cars. One gallon of gas causes 20 pounds of carbon pollution. And the mean fuel economy in California is ~ 25 miles per gallon. So, 25 miles driving = 20 pounds carbon pollution. (chart source:…)
Low-income Californians drive an average of about 25 miles per day, while high-income Californians drive about 50 miles per day (rounding up slightly from 2015 data).
A wealthy Californian burns as much carbon in their cars in 11 days as I produce from electricity (from PG&E) in a year -- about 14,600 pounds of carbon per year.

A low-income Californian burns as much carbon in their cars in 22 days as I produce from electricity in a year.
If a tall building cut my solar production by half, to ~ 3.2 MWh, the carbon from electricity on the grid would increase by 659 pounds.

If 10 low-income people lived in that building and each reduced their driving 50% (I'm four blocks from BART/bus/Berkeley Bowl)...
... they would cut carbon pollution by a collective amount of 36,500 pounds per year.

36,500 is more than 659.

If four wealthy people lived in luxury condos in that building and reduced their driving 50%, they would cut carbon by a collective amount of 29,000 pounds per year.
29,000 is *also* more than 659.

So, if you take my assumptions about density (more homes for lower-income apartments and fewer homes for luxury condos), the net benefit to the climate of building homes where people don’t have to drive ...
... but whose homes might block my solar panels and reduce their output by 50% -- is approximately 100x greater for low-income people, and 50x greater for high-income people.

And even if you completely blocked my solar panels, the cost/benefit ratios would be off the charts.
Do I want my solar panels to be blocked? Not particularly. But I bought them because I want to live a zero-carbon lifestyle in a zero-carbon city.

If building more homes that block my solar panels results in significantly less carbon emissions, then that is what I want.
If Berkeley is serious about climate action, then it will shitcan this stupid, NIMBY-driven shadow item and focus on the goal: cutting carbon emissions, by all means necessary, as fast as possible.

In Berkeley, that means more homes.…
cc: @KateHarrisonD4 and @SophieHahnBerk who seem to love all the glamour about climate action right up until someone asks them to show their climate math.

Here's my math, Kate and Sophie. It's been many, many years, and I'm still waiting to see yours.

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More from @mateosfo

3 Nov
I missed this while I was in the desert, but ... we've reached the end of the USA.

Short thread about this news.

For decades, Republicans have been clear that their primary goal in taking over the Supreme Court was to end US environmental law.…
(the Taliban-wing of the GOP also savored the court because, for them, The Handmaid's Tale is a vision, not a parable)

But the Clean Air Act and Clean Water Act have always been the main kills in Republican crosshairs.

Both Acts rest on an interpretation of the commerce clause.
Under this interpretation, since pollution doesn't honor state lines, it can be regulated by Federal law.

@benjaminwittes wrote about this many years ago (also, fascinating to see how utterly wrong Wittes was about civil and reproductive rights):…
Read 9 tweets
3 Nov
Good news!! Electric vehicles are now 11% of new car sales in California!!

Bad news!! 45% of new car sales in California are trucks/SUVs that get less than 27 mpg!!

One step forward, five steps back.

On the bright side, zero progress is at least visible in the ~ near-future.
I’ve gotten so cynical about “clean cars” that I’m actually excited about the date, sometime in the late 2030s, when we reach zero progress. at least we know the backsliding will probably end in (some of) our lifetimes.

thanks, car industry, for the dose of hope?
(lest ye get your hopes up, this is California we’re talking about. In the rest of the US it’s monster trucks all the way down. We will pump $30 trillion into inefficient, oil-burning vehicles before EVs hit 50% of sales.)
Read 5 tweets
2 Nov
Some folks got pissed at me about this tweet because San Francisco won't literally look like Atlantis.

It's true, the San Francisco Archipelago is still just a dystopian fantasy world invented by @burritojustice (see…)

But let's talk reality a sec.
By 2050 we are virtually certain to see around ~ 3 feet of sea level rise. Sounds fine, right? You've got a cool condo in the Castro, elevation 200 feet. No problem.

Must be nice. Here's 101 in Mill Valley with 3 feet of sea level rise. The red part is underwater: Image
Here's Larkspur/Corte Madera: Image
Read 10 tweets
6 Oct
California is the largest consumer of oil in the United States.

Penalizing the oil industry for oil spills is good, since they're not supposed to do that.

But, we can be assured they will always spill the oil, because ... they're the oil industry. That's what they do.
One thing that's interesting about the politics of oil spills is, everyone rushes to talk about how they're going to fine the oil industry, crack down etc.

But nobody talks about the fines in context. So, I shall do so!!

For perspective: Let's take British Petroleum.
BP paid the largest fine ever levied against an oil company for the Deepwater Horizon disaster. That fine: $60 billion.

Sounds like a lot of money, right?

Well, it's about a third of their *annual* revenue from the sale of gasoline. Yes, it packed a punch; but, they covered it.
Read 8 tweets
6 Oct
About 35% of gasoline used by California drivers comes from California, including offshore.

And like rest of US, most cars sold in California are inefficient gasoline trucks & SUVs.

Californians say we don’t want our beaches covered in oil. But we pay to cover them in oil.
If I were a driver who also liked beaches not covered in oil, I would stop paying the car/oil industry to cover my beaches in oil.

Then, the car/oil industry wouldn’t have the money they need to cover our beaches in oil, and would have to stop putting oil on our beaches.
Some people think you can have oil and also have beaches that are not covered in it, but this is not the case. Oil always spills, because the humans who drill for oil always spill it.

And then there’s what happens after you burn it.
Read 5 tweets
5 Oct
I think what’s lost in discourse about “autonomous vehicles” is, in spite of our *conscious choice* to allow drivers to kill and maim millions each year, humans are actually exceptionally *good* at driving cars because our brains are straight up miracles of processing power.
I don’t believe anyone who claims any AV will ever - in any future - match the processing speed, reflexes, object sorting, audio/visual cue analysis etc. of a human brain. Maybe in a model.

But the problem isn’t that humans suck at driving. It’s that we suck at caring.
If we *cared* about safe streets, *we would already have safe streets.*

If we valued human life enough to prevent drivers from killing and maiming millions, *it would already have stopped.*

We don’t need AVs for that. But AVs are not designed to save human lives.
Read 4 tweets

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