HFO-1234yf Aircondition Refrigerant in Automotive Applications also R-1234yF

Toxic, Fluoride ions attached to a hydrocarbon
5% lower performance than R134A too //
CAFE Credits gave rise to Automotive USE
Lower Global Warming Effect than R134A 

R134A a common automotive HVAC refrigerant since the 1990's, but government CAFE credits given to automakers to use lower global warming potential refrigerants gave rise to the widespread utilization of newer HFO-1234yf refrigerant from Honeywell & Dupont (R-1234yf), companies that have a long history of making specialized chemicals for use in such pure expansion based compressor cooling & water vapor condensing systems for automotive applications. 

In an automobile engine or motor bay, where the gasoline engine or electric traction motor are often located, a electric motor driven, belt driven or gear driven compressor used to create a differential pressure in a high pressure heat pumping system known as an air conditioner, used to remove water vapor from the cabin air during cold winter weather where the outside air temperature cools the front window such that water vapor from people breathing it out inside the cabin or the car or moisture in the air outside the car, condenses forming a visibility blocking fog in the inside or outside surface of the front window. 

Heat from the engine or heaters can heat air blown by electric fan motors in defrosting modes that warm the front window to help boil off the water vapor in the inner & outer surface to improve visibility though the front window during winter weather, while AC compressor systems also used to cool the cabin when the vehicle is operated in hot or very warm weather during the summer. 

Thus automotive HVAC systems are important for safety & comfort in winter & summer operating conditions, though primitive or simple window heating sufficient for defrosting in the winter, and opening the windows at low speed can accomplish limited passenger cooling during hot summer conditions. Nonetheless most modern automobiles feature a compressor based HVAC system for defrost & cabin cooling, with air filtering to improve the inside car air quality since traffic corridors tend to have a higher concentration of poisonous or toxic particles & fumes, mostly from the tailpipes of vehicles powered by engines that burn gasoline or diesel, though tire & brake dust are also poisonous and toxic to human health. 

I have argued before & will say it again, cars or automobiles are not a great personal transportation device platform for billions of people, namely because its not feasible to make that many cars or fuel or charge them if they are EV's, and traffic corridors & signal controlled intersections and roadways lack the capacity to handle such volumes, and parking that many cars presents a serious space problem in many big cities already and would only be much worse if everyone on Earth owned a car. I live in a suburban quasi rural area where no real services are walkable from my home. 

This means that the only practical way of getting around locally is with a car, truck, SUV or other privately owned automobile of some kind. That could be a E-bike, scooter, motorcycle, or quad, but for safety, practically, utility space for shopping at Costco or Safeway or FredMeyer, most people who work or who have children, also own a car or van or SUV or truck and use their privately owned automobile to move their body, stuff, their children, groceries, furniture & many other items, tools, etc, around to make life happen. This means that owning a car the only practical transportation solution for many Americans. America is also where the automotive revolution took place in a big way earliest. 

This means that most American families own 2 or more automobiles, typically fueled by gasoline, though the latest most popular models are LIB or lithium ion battery electric vehicles, namely the Tesla Model S, 3,X, & Y, and soon the Cybertruck, though I see many other kinds of EV's from VW ID to Lucid Air, Audi E-Tron & many other EV's being driven locally by high income persons that live in King County, Washington State, USA, with lots of disposable income to waste on rapidly depreciating luxury vehicles. I am a technophile or technological enthusiast, scientist, tech nerd, nerd, and have been obsessed with vehicles, energy, technologies, and science since I was a young child. Especially computers. 

I love God the most & my wife second to God, but I really like technology & thats why I noticed the Air Condition Sticker inside the hood of our 2022 Toyota Corolla Hybrid. Due to being ill with a flu & then cold virus back to back, I missed work and this car sat idle without being driven for 10+ days. The Wet or Flooded SLI battery in the engine bay was at 11.8vdc when I opened the hood & tested it, so I hooked up a 10amp automatic battery charger & it took about an hour to full charge the battery. 

I was standing there at the front of the car in the cold morning air monitoring the $27 Chinese fully automated battery charger to make sure it did not short, malfunction or catch fire, even though its only 7 deg centigrade outside or around 44F, winter time, and the fan cooled charger did not even warm up nor did the battery during charging, which started at over 10amps then ramped down to less than 1amp towards the end when the charger indicated a full charge. 

While I was in the engine bay I was looking at the 2ZR-FXE engine & stickers placed around the engine bay when I noticed the Air Conditioning Charge sticker saying it contained R-1234yf, which I had never heard of. So I came inside for a few minutes & looked it up online, and found this information. All of my other earlier past automobiles contained R12 then later models R134A, so this the first & only vehicle to use this new type of air conditioning system.

The automakers resisted switching from R134A to R-1234yf because R134A about 5% more efficient & can be used in cheaper systems with less robust components. To make use of the patented new R-12344yf the automakers are forced to use newer more precise compressor, larger more efficient more expensive condensers, leak proof oil recuperators, and thicker pipes with better gaskets & better sealing, meaning the entire AC system heavier, more complicated & more expensive, though the Automakers went this route because they got credits in the C.A.F.E system meaning they actually make more money by using the new system, since it helps them achieve their corporate average fuel economy scores for tax credits & to avoid paying fee's. 

Chemically HFO-1234yf a hydrofluoroolefin or HFO, the first of a new class of refrigerants, also blended as a component of R-454B in air conditioning & heat pump systems. Chemours calls it Opteon YF while Honeywell calls it Solstice YF. Governments gave automakers incentives to adopt HFO-1234yF because it has a GWP or global warming potential score of less than 1, or 4 during its lifetime after it leaks out of older automative HVAC systems as they break down & leak during long life or toward EOL or end of life operating. Nothing lasts forever since entropy breaks everything down. This means all mechanical systems have a finite useful life, after which they will fall apart or break down, leak, rust, corrode, become ashes & dust eventually. Even people can't get out of here, Earth, alive, since every human person eventually dies. 

As of model year 2022 about 90% of vehicles make use of the HFO-1234yf refrigerant. One environmental concern is how it eventually breaks down into a POP or persistent organic pollutants of the PFCA or perfluorinated carboxylic acids, sort chain molecules that are poisonous to life on Earth.

Barbara Haviland Minor & her team at DuPont developed HFO-1234yf working with engineers at Honeywell to comply with the European directive 2006/40/EC effective 2011, requiring all new cars sold in Europe to use an AC system with a GWP or global warming potential of less than 150. The 100 year GWP of HFO-1234yf less than 1, and can be used in R134a systems. 

R134A has a GWP of 1430 by comparison. Of the available lower GWP systems, HFO-1234yf systems were the least costly for the automakers to adopt into existing assembly lines with virtually no modification, other than the improved hardware required to use the new HFO-1234yfd with ND 11 oil. Servicing HFO-1234yf systems requires specialized equipment because of flammability and specialized oil. The service plugs or ports for recharging HFO-1234yf are different than R-134a, to prevent the charging of newer systems with older refrigerants or the wrong lubricating oil. ND 11 used because it resists combustion even if oxygen introduced to the system. 

Systems exist that mix 10-15% R-134A with the HFO-1234yf to make it not flammable R451A & R451B, with a resulting GWP of 147, below the 150 rating score required by the European laws. 

In collisions where HFO-1234yf leaks, it breaks down into trifluoracetic acid, a strong organic acid that is also phytotoxic without any known biodegradation mechanisms in water. When combusted by fire, HFO-1234yf releases corrosive toxic HF over hydrogen fluoride gas, and carbonyl fluoride a highly toxic gas.