Bioenergy Crops: the Good, the Bad & the Ugly
Alternative Agricultural Enterprises for the Treasure Coast
October 19, 2011
Tim Gaver , Extension Agent – CitrusIFAS/St. Lucie Extension
Why Grow Bioenergy Crops?
• Biomass: A renewable biological energy source used to produce heat, ethanol or biodiesel
• South Florida would seem to be ideal for biomass production because of available acreage, long growing season and rainfall
• U.S. is dependent upon imported petroleum for over 60% of its transportation fuels
Demand for BioFuels
• U.S. Renewable Fuel Standard (May, 2009)
• Mandates use in US of 36 billion gallons of renewable transportation fuel by 2022- 16 billion gallons cellulosic biofuels- 15 billion gallons corn-based ethanol- 1 billion gallons biodiesel- 4 billion gallons advanced biodiesel
• - Mandates by the U.S. Navy and Air Force to significantly reduce their dependence on petroleum jet fuel
Ethanol Production
• Corn or “sugar” ethanol - 200+ plants in US producing >14 billion gallons- Cost of production about $1.40 per gallon
using Midwest corn- Cost estimated at $2.00 per gallon using
Florida –grown corn- Sugarcane generates more $ from sugar
than from ethanol- US will export 900 million gallons in 2011- Food vs Fuel controversy
• Cellulosic ethanol- US production this year estimated at 6.6
million gallons- Only about 33% as efficient as corn
ethanol
Cellulosic Ethanol
• Estimated 94 million tons of
biomass annually could be produced in Florida
• Potential for 8 billion gallons of cellulosic ethanol
• BP/Verenium is building a new plant in Highlands County
($250 million+)
• Potential feedstocks:- Energy cane- Sweet sorghum- Giant reedgrass- Elephantgrass- Switchgrass- Miscanthus- Yard waste
“Energy” cane
• Sugarcane varieties that have high stalk contents of sugar and fiber
• Scientists working on varieties with increased cold tolerance
• Grown the same as conventional sugarcane
• 1200 gallons ethanol per acre?
Sweet Sorghum
• Silage types for ethanol• 2 crops from one planting
in early spring• Must be grown as a
rotational crop• Needs less water &
fertilizer than sugarcane• Yields of 15+ dry tons• 160 – 400 gallons ethanol
per acre• New variety research for
higher yields and pest resistance continues
Giant Reedgrass
• Arundo donax• Considered invasive in
some states• Grown from rhizome or
stem pieces• Can grow in wet soils• 20+ tons per acre• Requires 60 lbs N per
year on mineral soils• Harvest every 7-12
months (once /yr optimum)
• More research needed
Elephantgrass
• Pennisetum purpureum
• Many varieties• Established with stem
pieces• 20 tons per acre• Needs 150-300 lbs N per year• “Do not plant” list in
South Florida
Miscanthus & Switchgrass
• Miscanthus (Miscanthus x giganteus
(Sterile hybrid)• Switchgrass (Panicum
virgatum)• Research showed both
of these plants grow too slowly in Florida
Kenaf
• 6 month crop• Grows 15+ feet high• Dried and pelletized
for burning in electrical power plants
• High cellulose content• 6-10 tons/acre
Biodiesel and *Advanced Biofuel Crops
• Seeds or nuts are crushed to remove the oil
• Canola• Camelina• Sunflower• Jatropha• Soybean• Peanut• *Algae
Canola
• Brassica napus• Normally grown in the
upper Midwest• USDA trials in Ft. Pierce showed problems with downy mildew & aphids
Camelina
• Camelina sativa• Oilseed crop normally
grown in the Midwest• 85-100 day crop• 38-40% oil • Stops growth at 85°• Up to 2000 lbs/acre• 2000 x $0.12 = $240• Cost of production $400+
- Land Preparation- Seed- Fertilizer
Sunflower
• 70 day crop from seed• Susceptible to excess
rainfall, insects, nematodes, fungus disease and a plant virus
• Low inputs, accept fertilizer
• Research needed for varieties adapted to Florida
Jatropha
• Jatropha Curcas L.• Normally grown in
tropical areas• High oil content (45%)• Production increases
with inputs• Must be harvested 3X
per year• Not cold tolerant!
Land Preparation
• Necessary for successful production in South Florida
• Shallow beds provide drainage following heavy rainfall
• Drilling preferable to broadcast seeding
• Harvest efficiency increased in level fields
A Short Summary
• No sustainable bioenergy crop opportunities for small farmers at this time
• Biofuel crops need variety research and a local crushing facility
• As cellulosic ethanol technology improves, funding for new plants will become available
• Opportunities for production of biomass will increase as a result
Thanks!
Questions?
Thanks to: Dr. Dan Chellemi, USDA, ARS, Ft. Pierce Dr. John Alleyne, IFAS/Sarasota Extension Dr. David Wright, IFAS/NFREC