NREL Cellulosic Ethanol Innovation Lab ∨

GOAL

Make cellulosic ethanol cost-competitive

CHALLENGE

Existing processes are energy intensive

METHOD

Innovation Lab

OUTCOME

Design improvements that could see a 20 percent yield increase and also net massive savings in capital and operational expenses.

OVERVIEW

Cellulosic ethanol is an alternative to gasoline that is produced from the woody and grassy parts of various plants like switchgrass.

In contrast to first-generation biofuels, such as corn ethanol, cellulosic ethanol does not use food crops as feedstock and does not need to compete with food crops for land. Despite these benefits, cellulosic ethanol currently costs more to produce than corn ethanol because the feedstock must be broken down into its components before being fermented into a combustible alcohol.

Seeing an opportunity for innovation, RMI and the National Renewable Energy Lab (NREL) convened a diverse group of experts in June 2007 to devise strategies for reducing the capital and operating costs of the biological conversion process.

The organizers set a goal of making cellulosic ethanol cost-competitive first with corn ethanol and ultimately with gasoline.

Participants began the workshop by touring NREL’s pilot commercial-scale enzymatic hydrolysis cellulosic ethanol plant to understand the current production process.

After the tour, the group embarked on two days of discussion, reflection, and planning -- alternating between small, focused breakout groups and larger feedback and plenary sessions.

The result -- participants identified over two-dozen distinct design improvements that could potentially result in a 20 percent higher yield with a capital cost savings of $29 million and operational expenses savings of $22 million per year.

These cost reductions included a roughly 50 percent reduction in plant energy demand.

Taken together, the design innovations could result in a break-even price of $1.08 per gallon of ethanol.