The Real Ground Zero for Renewable Fuels is Dirt

By Craig Patterson | March 11, 2011

Every day seems like the dawn of a potential new era in biofuels. Technology announcements of advancements in enzyme efficiencies, fast pyrolysis reactors, new thermochemical methods and cellulosic ethanol breakthroughs pepper the news. The race to convert biomass to fuel on a commercial scale is a dizzying and important one if we are to truly replace fossil fuels.

The most important race is not in conversion of biomass, however, but in the actual growing of biomass.

The market for new, high-performance energy crops suffers from “the chicken or the egg” conundrum. End users won’t commit to utilizing energy crops without large-scale availability of feedstock. And growers won’t commit to planting it without large-scale demand from end users. Someone must take the risky first move, and it’s going to have to be the growers.

I recently watched a planter demonstration in a field of miscanthus on a farm in central Georgia. Miscanthus, alongside switchgrass, is a perennial energy grass with great promise as a biofuel crop, especially in the Midwest and Southeast. The crop produces up to 20 tons per acre—far more biomass than trees or switchgrass—so it seems to be an easy answer to the problem of reliable, efficient and environmentally friendly feedstocks. The problem with miscanthus is in establishment. The crop only reproduces from cuttings called rhizomes—actual pieces of the underground plant system that must be dug up and replanted, at the rate of around 5,000 rhizomes to the acre. The speed and cost of planting, it turns out, is a large bottleneck in viability of this crop as a successful feedstock.

Here is a quick bit of math to illustrate this bottleneck. Current planting technology can plant, at best, 20 acres per day. Let’s assume that a biorefinery needs 3,000 acres of crop on which to run. That 3,000 acres would take 150 days to plant. By the time planting was done, the planting season would be long over. Putting five pieces of equipment on site reduces the planting to 30 days, but imagine that the planting is going on in five different states, on 15 different farms. Suddenly you need 75 teams planting all at once, across several states. In this scenario, 45,000 acres—a drop in the bucket of what is required—would require millions of dollars of equipment and labor to achieve. And that is a bottleneck.

Back at that farm in central Georgia, the planter we watched might double the speed of planting. A planter my company is working on might triple or quadruple that speed. It’s a vital point in the energy supply chain. Farm machinery, it turns out, is critical to the ability to make the feedstock affordable, and therefore critical to the race to renewable biofuels. The inventor of this particular machine isn’t wearing a lab coat and doesn’t have a degree in chemical engineering, but he’s at the forefront of the race towards commercially viable biofuels.

This is just one example of the hurdles my industry is working on in bringing the best biofuel feedstocks to market. Add to this equation weed control, fertilizer optimization, harvesting efficiencies, proper storage and handling and you can quickly see the array of potential bottlenecks to cellulosic feedstocks.

There are only a handful of companies tackling the problem of commercializing energy crops. And, fortunately, we enjoy the fact that we are technology independent. It doesn’t matter which conversion “wins” in the end, whether pyrolysis, gasification, enzymatic conversion or microwave bombardment. No matter what, the crops must be in the ground and growing at maximum efficiency. Fortunately for the U.S., we have some of the most savvy, creative and crafty innovators in the history of man working on these problems—the American farmer.

The American farmer has already commercialized growing on a monumental scale through innovations that rival that of the information technology industry for speed of change. Corn, soybean, cotton and wheat production yields are often-ignored testaments to this fact. This same dedication and quickness is critical now to America’s energy independence.

Author: Craig Patterson
Manager of Commercial Operations,
REPREVE Renewables
(888) 447-6938