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There is no doubt now that energy is fundamental to our development. Global energy trends such as higher energy demand and prices, big differences across regions, structural changes in an oil and gas industry increasingly dominated by national companies, the prospect of irreversible climate change, as well as demand for energy security all highlight the need for a rapid transition to a low-carbon, efficient and environmentally benign energy system. The search for energy alternatives involving locally available and renewable resources is one of the main concerns of governments, scientists and business people worldwide. As researchers tackle problems according to global trends, an overwhelming body of research focusing on bioenergy in relation to other types of renewable energy might illustrate the role bioenergy has as the most important renewable energy source for the near and medium-term future. Thus, analyzing the amount of existing research, we found that about 50% (4,911 records) of 9,724 renewable energy records available were bioenergy records. We also found that publications on each of the four main sources of biomass (agriculture, forest, waste and other) represent about one quarter of the 4,911 bioenergy records retrieved. Biomass – the fourth largest energy source after coal, oil and natural gas - is the largest and most important renewable energy option at present and can be used to produce different forms of energy. As a result, it is, together with the other renewable energy options, capable of providing all the energy services required in a modern society, both locally and in most parts of the world. Renewability and versatility are, among many other aspects, important advantages of biomass as an energy source. Moreover, compared to other renewables, biomass resources are common and widespread across the globe. The sustainability potential of global biomass for energy is widely recognized. For example, the annual global primary production of biomass is equivalent to the 4,500 EJ of solar energy captured each year. About 5% of this energy, or 225 EJ, should cover almost 50% of the world's total primary energy demand at present. These 225 EJ are in line with other estimates which assume a sustainable annual bioenergy market of 270 EJ. However, the 50 EJ biomass contributed to global primary energy demand of 470 EJ in 2007, mainly in the form of traditional non-commercial biomass, is only 10% of the global primary energy demand. The potential for energy from biomass depends in part on land availability. Currently, the amount of land devoted to growing energy crops for biomass fuels is only 0.19% of the world's total land area and only 0.5-1.7% of global agricultural land. Although the large potential of algae as a resource of biomass for energy is not taken into consideration in this report, there are results that demonstrate that algae can, in principle, be used as a renewable energy source. From all of these perspectives, the evidence gathered by the report leads to a simple conclusion: Biomass potential for energy production is promising. In most cases, shifting the energy mix from fossil fuels to renewables can now be done using existing technology. Investors in many cases have a reasonably short pay-back because of good availability of lowcost biomass fuels. The latter is of course dependant on local incentives, however. Overall, the future of bioenergy is also to a large extent determined by policy. Thus, an annual bioenergy supply covering global energy demand in 2050, superseding 1,000 EJ, should be possible with sufficient political support. Global production of biomass and biofuel is growing rapidly due to the increasing price of fossil fuels, growing environmental concerns, and considerations regarding the security and diversification of energy supply. There are many scenarios that predict a high potential for biomass in the future. There have also been many studies performed in recent decades to estimate the future demand and supply of bioenergy. Overall, the world's bioenergy potential seems to be large enough to meet the global energy demand in 2050. The current stock of standing forest is a large reservoir of bioenergy and in line with the theoretical potential of biomass energy. However, most of the research studies on biomass potentials ignore existing studies on demand and supply of wood, despite the extensive literature and data on the subject. Taking into account data from a variety of international sources, rough estimates of the energy production potential of woody biomass from forestry show that, in theory, the demand for wood fuel and industrial roundwood in 2050 can be met, without further deforestation, although regional shortages may occur. However, the shift in the energy mix requires much more investment in infrastructure, equipment and in some cases R&D. Moreover, a prerequisite for achieving bioenergy's substantially high potential in all regions is replacing current inefficient and low-intensive management systems with best practices and technologies.