𝗪𝗲 𝗵𝗮𝘃𝗲 𝗱𝗶𝘀𝗰𝘂𝘀𝘀𝗲𝗱 𝘀𝗲𝘃𝗲𝗿𝗮𝗹 𝘁𝗶𝗺𝗲𝘀 𝗵𝗼𝘄 𝗚𝗪𝗣 𝗮𝗻𝗱 𝘁𝗵𝗲 𝗙-𝗚𝗮𝘀 𝗳𝗿𝗮𝗺𝗲𝘄𝗼𝗿𝗸 𝗮𝗿𝗲 𝗿𝗲𝘀𝗵𝗮𝗽𝗶𝗻𝗴 𝗿𝗲𝗳𝗿𝗶𝗴𝗲𝗿𝗮𝗻𝘁 𝗰𝗵𝗼𝗶𝗰𝗲𝘀 𝗶𝗻 𝗛𝗩𝗔𝗖/𝗥.

 

But when HFOs, natural refrigerants and other low-GWP solutions are compared, one parameter deserves more attention:

𝗧𝗘𝗪𝗜, 𝗧𝗼𝘁𝗮𝗹 𝗘𝗾𝘂𝗶𝘃𝗮𝗹𝗲𝗻𝘁 𝗪𝗮𝗿𝗺𝗶𝗻𝗴 𝗜𝗺𝗽𝗮𝗰𝘁.

➡️ With GWP, the hierarchy between refrigerants appears immediate.
➡️ With TEWI, the result has to be calculated for the application.

Consider three different systems.

✔️ A 𝘀𝘂𝗽𝗲𝗿𝗺𝗮𝗿𝗸𝗲𝘁 refrigeration system may operate almost continuously, with a relatively large refrigerant charge and significant exposure to leakage.

✔️ A 𝗿𝗲𝘀𝗶𝗱𝗲𝗻𝘁𝗶𝗮𝗹 heat pump has a smaller charge, seasonal operation and a result strongly influenced by seasonal efficiency and local climate conditions.

✔️ An 𝗶𝗻𝗱𝘂𝘀𝘁𝗿𝗶𝗮𝗹 chiller may remain in service for 15 or 20 years, making even relatively small efficiency differences significant when accumulated over its operating life.

➡️ The same technical solution can also produce a different TEWI depending on where it operates.

▪️ Electricity carbon intensity changes from one country to another.
▪️ Climate conditions change annual heating or cooling demand.
▪️ Leakage profiles differ between factory-sealed equipment and large field-installed systems.

➡️ This is why TEWI changes the comparison.

It combines:
▪️ direct emissions from refrigerant leakage and end-of-life losses;
▪️ indirect emissions associated with the energy consumed throughout the system lifetime.

A very low-GWP refrigerant can strongly reduce the direct component.

But the final result still depends on refrigerant charge, leakage, recovery, efficiency, operating hours, electricity mix, climate conditions and equipment lifetime.

This does not mean that TEWI necessarily reverses the advantage of lower-GWP refrigerants.
It means that the advantage should not be assumed from GWP alone.

𝗧𝗵𝗲 𝗰𝘂𝗿𝗿𝗲𝗻𝘁 𝘁𝗿𝗮𝗻𝘀𝗶𝘁𝗶𝗼𝗻 𝗯𝗲𝘁𝘄𝗲𝗲𝗻 𝗛𝗙𝗢𝘀, 𝗻𝗮𝘁𝘂𝗿𝗮𝗹 𝗿𝗲𝗳𝗿𝗶𝗴𝗲𝗿𝗮𝗻𝘁𝘀 𝗮𝗻𝗱 𝗼𝘁𝗵𝗲𝗿 𝗹𝗼𝘄-𝗚𝗪𝗣 𝗮𝗿𝗰𝗵𝗶𝘁𝗲𝗰𝘁𝘂𝗿𝗲𝘀 𝘀𝗵𝗼𝘂𝗹𝗱 𝘁𝗵𝗲𝗿𝗲𝗳𝗼𝗿𝗲 𝗯𝗲 𝗰𝗼𝗺𝗽𝗮𝗿𝗲𝗱 𝗮𝘁 𝘀𝘆𝘀𝘁𝗲𝗺 𝗹𝗲𝘃𝗲𝗹, 𝘂𝗻𝗱𝗲𝗿 𝘁𝗵𝗲 𝗮𝗰𝘁𝘂𝗮𝗹 𝗰𝗼𝗻𝗱𝗶𝘁𝗶𝗼𝗻𝘀 𝗶𝗻 𝘄𝗵𝗶𝗰𝗵 𝘁𝗵𝗲 𝗲𝗾𝘂𝗶𝗽𝗺𝗲𝗻𝘁 𝘄𝗶𝗹𝗹 𝗼𝗽𝗲𝗿𝗮𝘁𝗲.

➡️ TEWI does not change the direction of the refrigerant transition.
➡️ It changes the basis on which competing technical solutions should be compared.