Plant Biofuels & Green Technologies

Biofuel

fuel that contains energy from recent photosynthesis; renewable fuels that are produced from living organisms

Bioethanol

alcohol made by fermentation of sugars or starches, mainly from corn, sugarcane, or cellulosic biomass

Biodiesels

plant vegetable oils that are modified to produce diesel

how ethanol compares as transportation rating

69% of energy content of gasoline on a per volume basis, high octane rating, lower vapor pressure, corrosive to aluminum, and hygroscopic

Pros of corn ethanol biofuel

may reduce emission of greenhouse gases produced by fossil fuels & less reliance on foreign oil

Cons of corn ethanol biofuel

may increase prices, affect consumption of the food it is made from, and very inefficient to produce from the specific cop it is made from since it has a high input of water, fertilizers, & fossil fuels needed to grow it

1 : 1.2

Energy input to output ratio of corn ethanol biofuel

Pros of sugarcane biofuel

yields more ethanol per ton and requires less energy to produce

1 : 8

Energy input to output ratio of sugarcane biofuel

Cons of sugarcane biofuel

it only grows in hot, wet, tropical climates limiting its range of use b/c it doesn’t transport well

Cellulosic ethanol

made from breaking down farm waste, wood chips, and non food grasses like switchgrass

agricultural wastes and residues, forestry residues, and paper + paperboard products

things that could be used as cellulosic biomass

doesn’t require use of farmland

the pro of cellulosic ethanol

costly and difficult to make + energy intensive

the cons of cellulosic ethanol

Saccharophagus degradans

bacteria that produce useful enzymes for making cellulosic ethanol

Switchgrass

a perennial grass native of North America

has been researched as a bioenergy crop in the last few decades because it grows well in marginal lands, provides high yields of biomass w/ low input of water & fertilizers, and takes low energy to produce with a high energy output

1 : 20

Energy input to output ratio of swtichgrass

Pros of biodiesels

can provide up to 90% more energy than is required to produce it & can cut greenhouse emissions by up to 40%

Cons of biodiesels

can boost up prices of oil plants and replanting rainforests with palm oil plantations has many detrimental environmental effects