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