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Bioenergy is thought to have many advantages such as promoting economic well-being especially in rural areas and developing countries, allowing better use of unproductive land, increasing the energy security and reducing greenhouse gas emissions. However, the full potential of bioenergy can only be reached once problems associated with the large-scale production of biofuels have been addressed. The benefits and negative effects of biofuels must therefore be assessed case-by-case and must take the following factors into account:
It is important to note that energy production from biomass depends on the type of crop and its productivity among other things. For example, for a given amount of energy, corn requires twice as much land as sugar cane, and soybean more than ten-times as much. Replacing a fourth of the transportation energy by biofuels from sugar cane would require 17% of the world arable land (200% if using soybean). It is therefore unreasonable to expect that biofuels will ever completely replace fossil fuels. Instead, biofuels should be viewed as a potential energy source to be used in conjunction with others. More...
List of potential benefits and negative effects of bioenergy development
Different studies present the production of biomass for bioenergy as a new source of income for developing countries leading to a reduction of poverty and increased food security. In reality, the expansion of bioenergy can have both positive and negative impacts on livelihoods.
On the one hand, the production of bioenergy will likely create more jobs than those required for the import of fossil fuel. But the number of jobs that could be created will depend on the type of crop, as some require more work than others.
Also, the development of bioenergy could make energy available to rural areas which often have limited access to other energy sources.
On the other hand, bioenergy development can also lead to social conflicts such as land disputes and human rights abuses. For instance, to reduce transport costs and increase economic viability, facilities that convert the harvested biomass into biofuel should be located near energy plantations, but when large energy plantations supply centralized conversion facilities, it can result in increased concentration of landownership and displacement of traditional farmers that can lead to conflicts. Such problems can be reduced by shifting from a centralized to a more local management and by providing incentives to invest in small farms.
In addition, increases in the price of biofuel crops would likely encourage farmers to convert food croplands to energy crops. Competition for land and agricultural products may in turn increase food prices and therefore improve the farmers’ incomes – especially those who generate large surpluses. However, an increase in food prices would affect the poor especially in developing countries, the greatest impact being on those living in urban areas. More...
Globally, there are significant areas of land available for growing bioenergy resources, but few are located in regions with the highest future energy demands. For example in some highly populated Asian countries, most of the cropland is needed for food production, thereby limiting land availability for biofuel production. Significant amounts of bioenergy could, however, be provided in those countries through the use of agricultural and forest wastes, efficient energy conversion technologies and a cultivation system combining agriculture and forestry where trees and shrubs are among crops (agroforestry).
Many developing countries consider using degraded lands for the expansion of bioenergy plantations. This is thought to reduce erosion, restore ecosystems, regulate water flow and provide shelter for communities and agricultural lands. However, large-scale growth of a single energy crop can potentially threaten biodiversity, limit the amount of food available to domestic and wild animals, reduce soil fertility, and cause soil erosion. Furthermore, increased water use can affect the irrigation of food crops and potentially reduce food supply. Increased biomass combustion may also cause air pollution.
With regard to forests, increases in the demand for bioenergy could make way for additional energy crops resulting in a higher deforestation rate, while the opposite may occur if wood becomes the main resource for bioenergy. Deforestation leads to the release of carbon dioxide and to biodiversity loss. Economic incentives to produce biofuels have been blamed for the clearing of rainforests – especially in Malaysia, where nearly 80% of deforestation occurs to make way for oil-palm plantations. Even large areas of degraded forests are at risk. For example, China has announced plans to convert several million hectares of degraded forests and croplands to bioenergy plantations by 2015. These forests, while not in perfect condition, still absorb large amounts of carbon and maintain high levels of biodiversity.
Carbon dioxide (CO2) emissions are particularly high when plantations are established on drained peatlands. More than a quarter of the oil-palm plantations in Southern Asia are located in such areas. Indonesia holds the third place in terms of CO2 emissions after the United States and China because of emissions resulting from high deforestation rates, peat fires and peat decomposition. European biodiesel has contained palm oil and contributed to this trend.
In light of the many advantages and drawbacks to bioenergy development, countries must consider the long-term impacts of various energy alternatives. In particular, the amount of greenhouse gas emissions and the environmental impacts associated with production, including land-use change, should be carefully considered. To avoid negative impacts and maximise benefits, well-enforced land-use regulations are needed. More...
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