Qualitative vs Quantitative?

[turtlebanana]

For ''fuel cells'', one of the key knowledge points from the study design is:
The comparison of the use of fuel cells and combustion of fuels to supply energy with reference to their energy efficiencies (qualitative), safety, fuel supply (including the storage of hydrogen), production of greenhouse gases and applications


What do they mean by ''qualitative'' energy efficiency? When talking about energy efficiency, wouldn't you describe something as having like 90% energy efficiency? Isn't that quantitative? Am i misunderstanding something?

[khai.ling]

For ''fuel cells'', one of the key knowledge points from the study design is:
The comparison of the use of fuel cells and combustion of fuels to supply energy with reference to their energy efficiencies (qualitative), safety, fuel supply (including the storage of hydrogen), production of greenhouse gases and applications


What do they mean by ''qualitative'' energy efficiency? When talking about energy efficiency, wouldn't you describe something as having like 90% energy efficiency? Isn't that quantitative? Am i misunderstanding something?

Hello!

I'm pretty sure they just say "qualitative" because they don't really expect you to know the exact percentage efficiencies of each method - in questions you will most likely be referring to how fuel cells are more efficient at producing electricity due to a fewer number of energy transformations (chemical --> electrical) than with combustion (chemical --> thermal --> mechanical --> electrical).

Hope that helps!