[katieHaylor (OP)]

Charles asks:

I know that a 200 mph car is far more than a 100 mph car. So how much more is a minus 80 degree freezer than a simple minus 24 or 40 freezer? Which countries have them? How many does the UK have and are they near or in hospitals? What are they used for at present? Is the western world the only maker and user?

What do you think?

[alancalverd]

"Dry ice" - solid carbon dioxide - is common wherever food or medical supplies are packed  for passive transport at -79 deg C. It's very easy to make and handle, and a decent styrofoam picnic box is usually adequate for a few hours' air or land transport.

Once you get to shipping container or air pallet quantities, active refrigeration may be preferable - the integrated fridge-container is chilled at the factory and can be maintained by truck, ship or aircraft auxiliary power anywhere.

In a word, the stuff can arrive in its refrigerated container, wherever it is delivered. 

[evan_au]

To compare temperatures, scientists use the "Kelvin" scale, where 0K = absolute zero = absolutely impossible to reach.
- 300K is considered to be "room temperature" in an air-conditioned room (but it is expected to reach around 315K where I am, today).
- Standard vaccine refrigerators at your pharmacist or local doctor operate at 4C, like the main body of your refrigerator at home. 4C = 277K
- Your freezer at home operates around -20C = 253K
- Dry ice (frozen carbon dioxide) at atmospheric pressure  is -79C = 195K. As Alan says, this is used for food transport, requiring no active power supply
- Liquid Nitrogen is -196C = 77K. This is used industrially, and also in hospitals and dermatologists for freezing tissue samples and destroying cancer cells
- Liquid Helium is -269C = 4K. This is used in hospitals for cooling MRI machines.
- The closer you get to absolute zero, the more energy you must spend to get it down to that temperature - and the more power you must spend to keep it at that temperature.

So your standard vaccine fridge aims to reach 277K/300K, which you could consider to be "92% of room temperature". In many parts of the world, it is hard to guarantee even this temperature, so a temperature-stable vaccine will be essential.

You could consider Dry Ice to be 195/300K, which you could consider to be "65% of room temperature". This will require enhanced infrastructure to increase capacity at dry ice plants*, and produce the required number of "picnic boxes".

*I'm afraid that you can't consider a SARS-COV2 vaccine as a carbon sequestration project, since the carbon dioxide evaporates straight back into the atmosphere...

[Bored chemist]

Why all this talk about dry ice?
-80C freezers are commonplace in labs.
They are not cheap- lab equipment never is.
For example.
https://www.telstar.com/lab-hospitals-equipment/ultra-low-freezers/?gclid=Cj0KCQiAzZL-BRDnARIsAPCJs72JpiZ78dZhiCDbb3TBAqNbCP2pvTapE6QT-Lul3rR4mwhmulSXZukaAld3EALw_wcB

[alancalverd]

One current concern is the maintenance of vaccine cold chains, which I presume prompted the question. Small propane powered refrigerators have been used to get previous vaccines to field stations but AFAIK not below -20C.

Part of the fun of translating from lab to field is to develop an indicator that will show whether a product has indeed been maintained within its specified time/temperature envelope. The joy of dry ice is that you can pack and seal under controlled conditions. If there's any solid CO2 remaining at the destination you can assume the product is OK. If not, some kind of ball-in-liquid telltale will trip if the maximum transit temperature has been exceeded at any point.

[Petrochemicals]

200 mph cars tend to cost alot due to low uptake, if made for the mass market they would cost as much as if not less than a car that was made to go 100mph if it had low sales. The cost of an item to produce and the sale price are 2 different things. Mobile phones are incredibly technically expensive things, the cost to produce the first IPhone is very large, but it is only by using technology already developed and the mass production of new technology that makes them anywhere near affordable to the masses.  The actual maintenance of a 200mph car is far greater than a 100mph car if driven at their top speeds, fuel tyres servicing all happen far more frequently far beyond distance travelled.

Relating this to freezers, I imagine there will be manufacturers trying desperately to kick out small  freezers of the correct temperature in large volumes, so hopefully the price will not be too bad as compared to the niche market small uptake medical equipment. The maintenance  of these freezers I am not sure of and cannot think why they will cost more, but I do believe that they will cost more to maintain.

[Bored chemist]

and cannot think why they will cost more,

They either need thicker insulation (and thus have smaller capacities for a given size box so you need more building space and also need to buy more freezers) or they need to pump more heat out and thus need bigger components.

[evan_au]

How readily available are -80 degree freezers?

After you transport and store your vaccine in a -80C freezer...

...you need a rapid, reliable and accurate means to bring the vaccine back to something approximating room temperature (eg 15C to 37C).
- Injecting a vaccine that has only warmed up to (say) -40C will kill all the human cells that you rely upon to manufacture the spike-protein antigen.

[Bored chemist]

- Injecting a vaccine that has only warmed up to (say) -40C will kill all the human cells that you rely upon to manufacture the spike-protein antigen.

No. It won't.
For two reasons.
First, you don't usually inject a solid. Most vaccines are mainly water and  will undergo a phase transition on cooling to -40C
Here's an educational video about it: see the comment a1 1:30

Secondly, if you made up the vaccine in alcohol (which would probably wreck it but would keep it liquid at 40 below,) or you used a powder injection system, the very cold material would possibly freeze a small amount of tissue near the injection site, but the rest of the body would be unaffected.

To be blunt, raising the temperature rapidly to 37 degrees is literally "piss easy".

Dry ice is a good way to do two things.
It keeps the material cold in transit
It asphyxiates the driver if they are not careful.