
Summary of Solutions to Climate Change Ranked by Cost-Effectiveness - robertwiblin
http://www.drawdown.org/solutions-summary-by-rank
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schiffern
I can't say how good their data is, but the descriptions seem to leave
something to be desired.

For instance, the #1 most effective method listed is refrigerant management.
[http://www.drawdown.org/solutions/materials/refrigerant-
mana...](http://www.drawdown.org/solutions/materials/refrigerant-management)

> _Refrigerants, specifically CFCs and HCFCs, were once culprits in depleting
> the ozone layer. Thanks to the 1987 Montreal Protocol, they have been phased
> out. HFCs, the primary replacement, spare the ozone layer, but have 1,000 to
> 9,000 times greater capacity to warm the atmosphere than carbon dioxide._

They seem to suggest that this is an unintended side-effect, but fail to
mention that CFCs were no better in this regard (falling into that same
range). R-12, the most common CFC, has a global warming potential of 10,900,
or 10,900x that of CO2.

> _Through an amendment to the Montreal Protocol, the world will phase out
> HFCs—starting with high-income countries in 2019, then some low-income
> countries in 2024 and others in 2028. Substitutes are already on the market,
> including natural refrigerants such as propane and ammonium [sic]._

Propane and anhydrous ammonia are considered "first generation refrigerants."
They were phased out in favor of CFCs ("second generation refrigerants")
because unlike propane and anhydrous ammonia, CFCs don't explode or chemical
burn your lungs if your household refrigerator leaks.

[https://en.wikipedia.org/wiki/Thomas_Midgley_Jr.#Synthesis_o...](https://en.wikipedia.org/wiki/Thomas_Midgley_Jr.#Synthesis_of_Freon)

There _are_ better options, the imaginatively named "fourth generation
refrigerants." These include HFO-1234yf (nearly a drop-in replacement for
R-134a; incidentally this is used in the Tesla drivetrain chiller/air
conditioner), HFO-1234ze, and ironically enough CO2 (aka R-744, which is much
cheaper than the other two and runs more efficiently, but requires a system
redesign due to higher operating pressures).

[https://en.wikipedia.org/wiki/HFO-1234yf](https://en.wikipedia.org/wiki/HFO-1234yf)

[https://en.wikipedia.org/wiki/R-744](https://en.wikipedia.org/wiki/R-744)

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lostmsu
Does not mention fusion at all. People are so short-sighted. :(

