Consider the Following Three Applications of Fuel Cells for Producing $\mathrm { CO } _ { 2 }$

question 16

Essay

Consider the following three applications of fuel cells for producing electricity to power a vehicle.
(i) A proton exchange membrane fuel cell uses hydrogen produced by electrolysis using electricity generated by burning coal.
(ii) A proton exchange membrane fuel cell uses hydrogen produced by electrolysis using electricity generated by a photovoltaic array.
(iii) A solid oxide fuel cell uses methane as a fuel.
For each case discuss as quantitatively as possible
(a) The overall efficiency of converting primary energy to energy at the vehicle's wheels
(b) The $\mathrm { CO } _ { 2 }$ emissions per $\mathrm { MJ }$ of energy at the vehicle's wheels

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Definitions:

Paired Factors

Fundamental entities in genetics that occur in pairs and determine specific characteristics or traits of an organism.

Gametes

Sexual reproduction cells that unite during fertilization to form a new organism, with sperm being the male gamete and eggs the female gamete.

Genotype

The set of genes in our DNA which is responsible for a particular trait, as opposed to the physical expression of those genes which is known as the phenotype.

Phenotype

The collection of traits that can be seen in a person, which emerge from how their genetic makeup interacts with their surroundings.