Bio-ethanol: Grass not Corn
Jan 8th, 2008 by Matt
The BBC has a good summary of recent research into ethanol produced from switchgrass. What makes this study interesting is that it’s a large scale, “on the farm” analysis of what it actually takes to plant, grow, and harvest the crop across 10 different farms outside Lincoln, Nebraska over a period of five years. Previous studies have been based on small research plots over much shorter time scales.
The highlights:
- One acre of grassland is estimated to produce an average of 320 barrels of ethanol
- Grass-based ethanol delivered 540% more energy than was required to grow and manufacture the fuel (up from a previous USDA estimate of 343%)
- Production and consumption of the grass-based ethanol produced 94% less CO2 emissions than an equivalent volume of petrol
The key point for me is the energy delivered versus the energy required. I know the process for making ethanol from grass (or any cellulose) is harder than that required for corn (or other seeds/nuts), but the energy return in dramatically better. I’ll definitely be interested to see how this technology progresses.
