Also: "100% green" means different things based on who's selling it.

Green is not a descriptive term when it comes to energy.

Also, 100% is very difficult to actually achieve, especially since there is no way to tell if the electrons powering your lamp came from coal or solar. https://twitter.com/GlobalEcoGuy/status/1283050945719480331
Anthing that says "100% green" is achieving it through energy accounting and offsets/credits.

For example: A "green" electricity provider may simply overproduce solar power during the day, even though the lights in your apartment are running off natural gas at night.
Almost all of the electricity market is an accounting game.

Imagine a silo full of corn. Some kernels are organic. Some are GMOs, but didn't use pesticides. Some are GMO with heavy pesticide use.

There is no way to tell when you pull kernels from the bottom which is which.
That's how it is for the electricity market.

For liquid fuels and things like hydrogen, "green" can also be subjective.

Is E10 gasoline green? Or E85? Well, it depends on what the feedstocks are.

In the US, the main feedstock is corn. And most US corn is grown for biofuel.
If you're using corn as a biofuel feedstock, part of the "greenness" comes from accounting for the use of dried distiller's grains (DDG) as feed for livestock. DDG isn't organic (most is GMO corn).

DDG is a byproduct of ethanol production.
In a weird way, this means the more organic beef and dairy is sold to replace "conventional" beef and dairy, the less you can account for the carbon offsets in ethanol from the DDG.

Byproduct use is accounted for in corn ethanol emissions numbers.
And if you consider land-use change outside US borders, corn ethanol looks worse. (We buy food from other countries because we use land to make fuel.)

Corn stays a feedstock because of subsidies for farms to grow it. And it's a big, big part of the ag economy of the Midwest.
Switchgrass is a "greener" alternative to corn, mostly because it requires fewer inputs like fertilizer and water.

(N2O from fertilizers are very powerful greenhouse gases, and water takes a lot of energy to pump everywhere.)
As for hydrogen fuel cells, the vast majority of hydrogen isn't renewable. Natural gas steam reformation still requires methane, most of it from fossil sources.

That's right kids, hydrogen is mostly made from fracking.h
Hydrogen can also be made from renewable gases (like landfill methane). The thing a lot of people are working on is electrolysis, since you can use renewable electricity (wind/solar) to make it from water.

Problem is, electrolysis is really, REALLY, inefficient.
The other side of this is that because renewable electricity like solar is intermittent, storing energy by converting electrons to hydrogen could be one way to use the extra when prices are wacky. But it only makes sense if electrolysis become much more efficient.
Because capitalism, it doesn't make sense to store curtailed solar power as hydrogen. Battery storage is cheaper, but still not cheap.

Oh, plus there is no transmission and distribution system for hydrogen like there is for natural gas or electricity.
There are accounting tricks to lower the carbon footprint of electrical power for a company or state.

At night, California imports hydropower from Washington (which has the cleanest grid in the US, btw).
And this is where leakage creeps in.

If CA buys power from WA, and WA needs more power for domestic use, WA may buy power from states like ID, which has a dirtier grid.

Without storage, the best you can do is hide emissions through accounting.
So "100% renewable" is constrained both by technology and economics.

This is why energy economists (hi!) advocate for pricing of carbon through tax or cap-and-trade. A price on carbon would make batteries viable and EVs more by making fossil fuels more costly.
And a single state—even the size of CA—can't do it alone without leakage.

An example of leakage is a trucker who fuels up in Yuma and delivers cargo in San Diego. That tank of diesel is not affected by California's carbon pricing.
And if you think about it, it's easy to see where this is going.

The word "tax" is radioactive in politics—especially for conservatives—regardless of economic utility. And carbon pricing has a high risk of being regressive. (Hurting poor folks more than rich folks.)
By the way, this is one reason nobody should ever take libertarians seriously.

The market cannot fix systemic problems on its own without intervention from government. If it could, climate change wouldn't be a thing. No firm will pay for a negative externality on its own.
And that, my friends, is why "green energy" is so political. It affects consumers, farmers, fossil fuel cos, transportation, etc.

The modern economy is built on fossil fuels, and it won't be easy to just switch without government intervention, which requires political will.
And I'm not going to lie: The transition will cost money. Just because a carbon tax makes natural gas power more expensive doesn't make batteries cheaper; it just makes them cheaper relative to the natural gas.
This one reason why I'm so adamant that the WFH paradigm continues post-COVID. Transportation accounts for the majority of energy use and carbon emissions in the US.

Without a commute, you save a ton of energy and emissions.

WFH offers breathing room to develop more solutions.
You can follow @ACcurrently.
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