What Makes eNergy Tuber an ABF 
​(Advanced Biofuel Feedstock)
Sustainable Green Energy Crop? 

What factors are needed in a
​sustainable advanced biofuel crop? 
Feedstock
Nitrogen/A
in lbs
Yield in
gal/A
​Pounds of N per 100 gallon 
​Percentage of corn
Corn
210
400
52.5
100.0
Sorghum
160
500
32.0
61.0
Energy Tuber recommended
90
1800
5.0
9.5
​Energy Tuber
 SC test
45
1800
2.5
4.8
Current Status of SC Land​
How To Get 1.2
​Million Acres?
Trees - convert 350,000 acres of tree
​              farm land (of 11 million)
Cotton – 150,000 acres (of 347,000)
Hay – 480,000 acres (of  570,000)
Corn - 205,000 acres (of 423,000)
CRP - land 15,000 acres (of 30,000)
ENERGY TUBER Uses Less Land to Support 1.2 MGY Ethanol Than Other Feedstocks. Less Land means less diesel used for Tractors, less Chemicals and Water per Gallon of Ethanol Produced.  
Preliminary GHG (Green House Gas) Analysis of an Energy Tuber 
Dr. Richard Plevin, UC Davis
18 to 23 g CO2e MJ-1

The initial Green House Gas (GHG) analysis was calculated by Dr. Richard Plevin, of Transportation Sustainability Research Center, UC Berkeley. The initial analysis showed the ENERGY TUBER would reduce emissions, over 75%, with a carbon footprint of about 18 to 25% of gasoline. 
Compared to 95.86 for gasoline. Could be even lower if:
  • Dr. Plevin used a conservative conversion efficiency - 85%.  
    ​Could have a lower GHG score with higher conversion (estimated in laboratory tests to be 95%).
  • Would lower score if including low water useage compared to corn and other biofuel crops.
  • Would lower score if renewable energy was used to process the crop, like biogas made from the stillage and energy from waste from waste heat generated in processing the crop. 
  • Fermentation to ethanol in half the time of corn would reduce energy use. 
  • Did not take co-product credit for extracted protein for food products, and Energy Tuber vines for feed.
Greenhouse chambers with CO2 pumped under Energy Tuber plants to be taken up during Photosynthesis.  
Instrumentation that measures CO2 uptake and Photo-synthesis rates on actively growing ENERGY TUBER plants.