Emergy Analysis and Sustainability Efficiency Analysis of Different Crop-Based Biodiesel in Life Cycle Perspective

Table 2

Calculation of the available energy of each item for soybean-based biodiesel.

Sunlight	Area = 23304.59 m^2
	Insolation = 4.77𝐸+9 J/m^2/yr
	Albedo = 0.3
	𝑇=0.35 yr
	Energy (J) = (Area) × (Insolation) × (1 − Albedo) × 𝑇 = 1.17𝐸+13 J
Rain geopotential	Area = 23304.59 m^2
	Rainfall = 0.3 m
	Rain-off rate = 0.20
	Average elevation = 100 m
	Density = 1000 kg/m^3
	Gravity = 9.80 s/m^2
	Energy (J) = (Area) × (Rainfall) × (Rainoff rate) × (Average elevation) × Density × Gravity = 1.37𝐸+09 J
Rain chemical potential	Area = 23304.59 m^2
	Rainfall = 0.3 m
	Density = 1000 kg/m^3
	Gibbs free energy = 1940 J/kg
	Energy (J) = (Area) × (Rainfall) × (Density) × (Gibbs free energy) = 1.36𝐸+10 J
Wind	Area = 23304.59 m^2
	Air density = 1.23 kg/m^3
	Drag coefficient = 0.001
	Average annual wind velocity = 2.4 m/s
	Geostrophic wind = 10 Average annual wind velocity/6 = 4.17 m/s
	𝑇=0.35 yr
	Energy (J) = (Area) × (Air Density) × (Drag coefficient) × (Geostrophic wind)^3 × (3600 × 24 × 365 × 𝑇) = 2.29𝐸+10 J
Topsoil loss	Area = 23304.59 m^2
	Topsoil loss energy = 1.32𝐸+09 J/hm^2
	Energy (J) = (Area) × Topsoil loss energy = 3.08𝐸+09 J