An old-school material could offer an a low-tech solution to our renewable energy needs — but not without some significant changes to the way we treat it now.
Using wood in bioenergy — a process that turns organic matter into fuel — may offer a potential renewable energy source that benefits the climate in more than one way.
At the same time as powering our homes and businesses, investing in wood bioenergy could also help keep trees alive and healthy. Boosting the world's forests may be critical to curbing global warming, as forests take in and sequester carbon dioxide.
But the idea presents a paradox. Turning to wood for bioenergy means burning trees, which means depleting forests, not saving them.
A new study tries to reconcile these ideas, suggesting that strong environmental policies would make it possible to both capitalize on wood bioenergy and protect forests.
To come to their conclusion, the researchers modeled different timber harvesting and management scenarios in more than 200 forests worldwide.
The found that, with proper land management, and close attention to timber economics, the benefits of using wood for energy would outweigh the costs of increased tree cutting.
The study was published on Wednesday in the journal Science Advances.
Weighing the pros and cons
If done correctly, the laws would ensure that large portions of environmentally valuable, old-growth forest remain untouched, the researchers say.
The benefits could be twofold:
“Incentivizing both wood-based bioenergy and forest sequestration could increase carbon sequestration and conserve natural forests simultaneously,” the researchers write.
Making sure the balance is favorable would require some serious regulations, the researchers say. Using wood-based bioenergy increases demand for wood, making forests more profitable. That can have resounding effects on prices, harvests, forest area, and how intensively forests are managed.
Over-harvesting can hinder the benefits that trees have in the first place — namely, sequestering carbon dioxide that would otherwise contribute to global warming.
Serious land-management policies would need to keep carbon emissions in balance, the researchers say.
But ultimately, more wood for bioenergy, they say, “will result in net carbon benefits, but an efficient policy also needs to regulate forest carbon sequestration.”
Part of the argument rests on the idea of supply and demand. As timber demand rises from the energy sector, so too would forested areas have to increase to supply the demand.
Every one percent increase in timber price, the researchers found, the forests grown to supply the wood would increase by about 0.32 percent. In the scenario tested in which wood bioenergy demand is highest, Earth’s forested areas could increase 30 percent by the year 2100.
But no matter the demand, policy will ultimately drive the protection of forests, the researchers say.
“Across all ranges of bioenergy demand, efficient forest carbon sequestration policies can be deployed to ensure that forests are carbon neutral and that forest carbon stocks are maintained,” the study authors write.
Abstract: There is a continuing debate over the role that woody bioenergy plays in climate mitigation. This paper clarifies this controversy and illustrates the impacts of woody biomass demand on forest harvests, prices, timber management investments and intensity, forest area, and the resulting carbon balance under different climate mitigation policies. Increased bioenergy demand increases forest carbon stocks thanks to afforestation activities and more intensive management relative to a no-bioenergy case. Some natural forests, however, are converted to more intensive management, with potential biodiversity losses. Incentivizing both wood-based bioenergy and forest sequestration could increase carbon sequestration and conserve natural forests simultaneously. We conclude that the expanded use of wood for bioenergy will result in net carbon benefits, but an efficient policy also needs to regulate forest carbon sequestration.