Have we ever wonder how brilliant if there a car generated by nuclear fuel (assume all the problems associated with the radioactivity and waste disposal of nuclear fuels are resolved) , and a car is to be powered by Uranium U-235. Actually this assumption sound impossible for today, but who knows if it possible in the future. I got this calculation from my thermodynamics textbook to show how nice if it possible.
Let say:
An average car consumes about 5L of gasoline per day, and the capacity of the fuel tank of a car is about 50L. Therefore, a car needs to be refueled once every 10 days. Also, the density of of gasoline ranges from 0.68 to 0.78 kg/L, and its lower heating value is about 44,000 kJ/kg (that is, 44,000 kJ of heat is released when 1 kg of gasoline is completly burned). If a new car comes with equipped with 0.1 kg of nuclear fuel U-235, determine if this car will ever need refueling under average driving conditions.
m gasoline = (rn)gasoline = (0.75kg/L)(5L/day)=3.75kg/day
Noting that the heating value of gasoline is 44,000kJ/kg, the energy supplied to the car per day is
E= ( m gasoline )(Heating value)
=(3.75kg/day)(44,000kJ/kg)=165,000 kJ/day
The complete fission of 0.1 kg of uranium-235 releases
(6.73x1010kJ/Kg)(0.1kg)=6.73x109kJ
of heat, which sufficient to meet the energy needs of the car for
No. of days= (Energy content fuel/Daily energy use)
= (6.73x109kJ/165,000 kJ/day)= 40790 days.
40790 days which is equivalent to about 112 years. Considering that no car will last more than 100 years, this car will never need refueling!!. It appears that nuclear fuel of the size of a cherry is sufficient to power a car during its lifetime.
