International Scholarly Research Notices

Review Article

Technoeconomic Assessment on Innovative Biofuel Technologies: The Case of Microalgae

Table 1

Comparison of biofuel feedstock environmental impacts for transportation fuels.


Crop type	Used to produce	GHG emissions^* (Kg of CO₂ created per mega joule of energy produced)	Use of resources during growing,				Pros and Cons
			harvesting, and refining of fuel				Pros and Cons
			Water	Fertilizer	Pesticide	Energy

Corn	Ethanol	81–85	High	High	High	High	Technology ready and relatively cheap; reducing food supply.
Sugar cane	Ethanol	4–12	High	High	Med	Med	Technology ready; limited as to where it will grow; reducing food supply.
Switch grass	Ethanol	−24	Med-low	Low	Low	Low	It will not compete with food crops; technology not ready.
Wood residue	Ethanol, biodiesel	N/A	Med	Low	Low	Low	Technology ready; reducing food supply.
Soybeans	Biodiesel	49	High	Low-med	Med	Med-low	Technology ready; reducing food supply.
Rapeseed, canola	Biodiesel	37	High	Med	Med	Med-low	Technology ready; reducing food supply.
Algae	Biodiesel	−183	Med	Low	Low	High	Potential for huge production levels; technology not fully ready for scale up.

^*Emissions produced during the growing, harvesting, refining and burning. Gasoline is 94, diesel is 83.
Data source: Adapted from [2].