Simply defined, sustainability is ensuring that future generations have access to the resources that we enjoy today. It was the topic of a recent workshop at the Cary Institute, where over forty ecologists discussed the sustainability of biofuel, an emerging source of alternative energy.
Most of us are aware of the negative impact that fossil fuel combustion has on the environment. Once controversial, climate change is now broadly accepted. Moving into the future, we must reconcile our need for energy with our need for a healthy planet.
A lot of hope has been pinned to biofuels. They hold the promise of being a renewable energy resource that is kinder to the environment. But are biofuels really sustainable or carbon-neutral? And which models are most likely to be effective over the long-haul? These were among the questions before workshop participants.
The biomass needed to make biofuel can come from an array of sources, from agricultural crops such as soy and corn to managed natural areas and landfill waste. Even algal blooms have been given consideration. To date, corn-based ethanol has received the most attention from industry and the media.
Workshop participants identified several critical flaws common to most agriculture- based biofuel models. Intensive farming, and subsequent fertilizer use, would degrade terrestrial habitat, freshwater ecosystems, and coastal oceans. Current biomass-to-fuel conversion technology is both inefficient and energy intensive. And, perhaps most insurmountable, there is not enough arable land to grow the sea of plant material that would be needed to replace fossil fuel with liquid biofuel.
Participant Dr. John Harte, a UC Berkeley professor with expertise in energy and global change, commented, “Starch- based ethanol does not make sense energetically or environmentally. There is too much degradation for too little energetic return. Biodiversity loss and pesticide pollution would be externalities passed along to future generations. ”
Workshop organizer Dr. Charles Canham, a forest ecologist at the Cary Institute, noted, “We need to be cautious about converting forests and natural areas into biofuel crops. Recent research has shown that this conversion releases 10 to more than 400 times as much CO2 as the potential annual savings from biofuels produced on those lands.”
For the time being, the most obvious energy solution is still energy conservation. Proceedings from the workshop will help provide research recommendations to the National Science Foundation. They will also be communicated to decision makers who need to understand the limitations of biofuel models. A brochure is forthcoming.
