Agriculture Reference
In-Depth Information
Rapeseed and canola require the application of fertilizers and pesticides in produc-
tion. The energy required to make these pesticides and fertilizers detracts from the over-
all net energy produced (Frondel and Peters 2007); conventional production of corn
requires energy inputs totaling 32 x 106 kcal per hectare, while production of a hectare
of corn using an organic system only requires a 3.5 x 106 kcal, though it requires 40%
more human labor. Organically grown corn reduces energy inputs almost enough to
balance energy inputs to the ethanol energy output, in addition to greatly decreasing the
environmental impacts of corn cultivation (Pimentel et al. 2008). Although soybeans
contain less oil than canola—about 18% soy oil compared with 30% oil for canola oil—
soybeans can be produced with nearly zero nitrogen inputs (Pimentel et al. 2008).
The biomass yield of rapeseed/canola per hectare is also lower than that of soy-
beans—about 1,600 kg/ha for rapeseed/canola compared with 2,890 kg/ha for soy-
beans (Pimentel et al. 2008; USDA 2004). The production of 1,568 kg/ha rapeseed/
canola requires an input of about 4.4 million kcal per hectare and costs about $669/ha
(Pimentel et al. 2008). About 3,333 kg of rapeseed/canola oil is required to produce 1,000
kg of biodiesel (Pimentel et al. 2008). Therefore, all 333 million tons of rapeseed and
canola produced in the United States in 2006 (USDA 2007) could be used to make 100
million liters of biodiesel, or 0.005% of the total oil used in the United States. The total
energy input to produce the 1,000 liters of rapeseed/canola oil is 13 million kcal. This
suggests a net loss of 58% of energy inputs (Pimentel et al. 2008). The cost per kilogram
of biodiesel is also high, at $1.52. Rapeseed and canola are energy-intensive and eco-
nomically inefficient biodiesel crops.
Oil Palm
There is a major effort to plant and harvest oil palms for biofuels in some tropical devel-
oping countries, especially Indonesia, Malaysia, Thailand, Colombia, and some in
West Africa (Thoenes 2007). From 1997-98 to 2012-13 the production of palm oil has
more than tripled, from 17 x 106 metric tons to 55 x 106 metric tons with production
by Indonesia and Malaysia accounting for about 85% of total world production (USDA
Foreign Agricultural Service 2001; USDA Foreign Agricultural Service 2013). Palm oil
makes up over 34% of vegetable oils produced worldwide (USDA, Foreign Agricultural
Service 2013a). The oil palm, once established after four years, will produce about 4,000
kg of oil per hectare per year (Carter et al. 2007). The energy inputs for maintaining the
hectare of oil palm are indicated in Pimentel et al. (2008). The data suggest that about
7.4 million kcal are required to produce 26,000 kg of oil palm bunches. This 26,000 kg
is sufficient palm nuts to produce 4,000 kg of palm oil. A total of 6.9 million kcal are
required to process 6,500 kg of palm nuts to produce one ton of palm oil (Pimentel et al.
2008). Thus, the net return on fossil energy invested in production and processing totals
30%. This is clearly a better return than corn ethanol or soybean biodiesel. However,
an estimated 200 milliliters (ml) (2,080 kcal) of methanol is a required addition to the
 
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