W ith increasing global population and advancing technological innovations, the energy demand is increasing at an alarming rate. On the other hand, consumption of non-renewable energy, fossil fuels, has stimulated climate change concerns. As a result, countries have been actively considering policies to increase the share of renewable energy consumption. When it comes to the increasing global demand of biomass for renewable energy, an important question is whether the bioenergy would be supplied sustainably.
We have taken an initiative to probe into this issue. Wood chip, used to produce paper and other products traditionally, has also been used to produce biofuel. Even though there has been fierce debate over treating wood as green source energy (see this recent Science article), the global demand for wood chip is increasing as policies promote the use of biomass for renewable energy. The lack of models to analyze the effect of local renewable energy policies on the global market of biomass prohibit policy makers from making sustainable renewable energy policies.
We built the first global trade model for wood chip using available wood chip trade data from FAOSTAT database. Our study focuses on how wood chip supply and trade would be affected by increased demand. We considered 5 different scenarios against the base case, which is the historical wood chip supply and trade between different countries during the year 2011.
Fig. 1 Comparison of export of wood chip from different regions between the base case and the first three scenarios. Exports from the Middle East, North Africa, Central America and South Asia were omitted here because they are negligible. Base case: actual exports in year 2011. Scenario 1: Increase in U.S. demand for cellulosic biofuel. Scenario 2: Increase in EU demand for renewable energy mandate. Scenario 3: Combined demand increase in U.S. and EU.
Fig. 2 Comparison of export of wood chip from different regions between the base case and the fourth and fifth scenarios. Exports from the Middle East, North Africa, Central America and South Asia were omitted here because they are negligible. Base case: actual exports in 2011. Scenario 4: Increase in U.S. demand for cellulosic biofuel and biomass power. Scenario 5: Combined increase in U.S. demand for cellulosic biofuel and biomass power and EU demand for renewable energy mandate.
Our model-based analysis using optimized Spatial Price Equilibrium(SPE) model would be a good tool to illustrate the type of effects that are likely to occur as a result of renewable energy policies such as the U.S. Renewable Fuel Standard(RFS) and the European Union’s Renewable Energy Directive(RED).
One of the most important consequences of increased demand for wood chip would be increased harvests. Our scenario analysis shows that the increased harvests will mainly come from tropical regions of Latin America and Southeast Asia, as well as the Former Soviet Union. If forest governance in some of these countries is weak, US and EU renewable energy policy could inadvertently exacerbate deforestation in these regions, leading to unsustainable development of bioenergy.
Global wood chip trade flow changes for base case
Fig 3. Global wood chip trade flow changes for base case. The regions are color coded based on the quantity of wood chip export.
Global wood chip trade flow changes for scenario 1
Fig 4. Global wood chip trade flow changes for scenario 1. The regions are color coded based on the quantity of wood chip export.
This quantitative approach to determine the effects of energy policies on the global market of wood chip supply and trade would be very helpful in making more sustainable bioenergy policy decisions. Further studies need to be carried out regarding the actual impact of the resulted changes in wood chip supply on the carbon stocks, biodiversity of the major sourcing countries. Our model can be combined with these further studies to investigate if a bioenergy policy is sustainable in a global context.