Course:CONS200/2019/The feasibility of using wood waste (logging slash) for bioenergy in BC

From UBC Wiki

In British Columbia, commercial logging for timber produces 85 million cubic meters timber from harvesting the forest land.[1] As how the overview of the BC forestry industry described, “British Columbia is the largest bioenergy producer in North America”.[1] This shows that the production of bioenergy is a significant source of energy in British Columbia. And one important fuel source for the production of bioenergy is the wood waste/logging slash generated from the process of harvesting and production of timber.

The wood waste generated from logging activities and production of timber brought many issues. Including fire hazards, nutrient losses from the soil, and many other detrimental effects for the environment.[1] And by using the wood waste and logging slash as a fuel source for bioenergy production, these factors could be prevented from effecting the environment

However, there are still many other issues related to the use of wood waste for bioenergy. The process is costly and inefficient comparing to other fuel sources. In order to determine the feasibility of the use of wood waste for bioenergy, the different scopes and viewpoints needs to be considered. The impacts and different perspectives towards this issue would reveal important information about the feasibility of using wood waste for bioenergy.

What is Bioenergy

Bioenergy is renewable energy produced from biomass found in biological resources. This sustainable energy has become more common globally because it has the potential to meet human demands. About three-quarters of the world's renewable energy involves bioenergy. Bioenergy provides 10% of total final energy consumption and 1.4% of global power generation.[2] Bioenergy is an outstanding energy resource compared to other renewable energy due to emitting less carbon dioxide and reducing waste. As a result, bioenergy will become widespread in the future.

In recent years, bioenergy has become one of the dominant energy sources for Canada. Currently, bioenergy provides approximately 6% of Canada’s total energy supply.[3] This energy can be used in personal and industrial capacities, such as electricity, transportation, industrial, agriculture, heating and cooking. Provincial governments in Canada have encouraged investment in bioenergy. In 2010, 51% of lodgepole pine volumes in British Columbia (BC) were killed by mountain pine beetle infestation. Therefore, "the provincial government raised the annual allowable cut (AAC) from 50 Mm³ to 80 Mm³ to harvest this dead pine for wood products and bioenergy before it decayed or burned in natural fires".[4] Moreover, the government of BC advocates the education, technology and application of bioenergy in the province, and have spent over $16.1 million in the development of bioenergy in British Columbia by the end of 2013.[4] In the BC Bioenergy Strategy, the government also creates economic opportunities related to the use of environmental resources to generate bioenergy. Those natural resources include mountain pine beetle damaged timber, municipal solid waste, sustainable agriculture, and sustainable forestry. The process of converting these biomass into bioenergy gives job opportunities to the BC population. Also, the government increase their economic income by generating 50 percent of the biomass electricity for Canada.[5]

the biomass resources that use for creating bioenergy in BC

Bioenergy can be converted into three different types of energy: biofuels, biopower and bioproduct.

  • Biofuel is converting biomass into liquid fuel which is similar to fossil fuel or oil. It is mainly used for transportation.
  • Biopower is burning biomass directly or converting it into a gaseous fuel or oil, which can be used for generating electricity.
  • Bioproduct is converting biomass into chemical form. It can be used for making products that are typically made from petroleum.

Bioenergy is important in global industries especially biofuel and biopower. Both of them make the process of production easier and more effective. They provide low and medium-temperature heat in paper and pulp industries, as well as the food processing sector.[6] Moreover, there are some other advantages using bioenergy in the modern era:[7]

  • it emits little or no net greenhouse gas emissions, which result in fewer pollution taxes.
  • it is reliable energy due to the consummate technology.
  • it is easier to manage.
  • it is storable and has minimal energy loss which is conducive for long-term production in the factory.
  • it reduces the pollution and erosion of the surrounding environment.
  • it can generate heat and electricity while converting into other products.

How wood wastes are used for Bioenergy

Waste converts into bioenergy

The burning of wood waste for biomass uses waste timber such as "wood chips, shavings, sawdust, splinters, remains of large-diameter wood after logging, waste from handling, tree stumps and roots.”[8] Healthy trees are not considered as a source for biomass energy. The most common use for wood biomass is direct combustion technology because it is relatively inexpensive, it is easy to handle and is very reliable. To be able to use wood waste as energy, however, there has to be some sort of modification in order to get as much energy as possible from the material. This refinement process leads to: “homogenization of material composition and size, the adjustment of moisture content, the modification of its composition, and the alteration of other physical and mechanical properties.”[8] The shape of solid biomass can also be optimized for better combustion as well as for better transportation of these to minimize costs.

One technology that could do this is densification, which presses wood waste into pellets and briquettes. Before doing this, the wood waste is sorted, disintegrated, and dried, which improves the properties of the biomass.[8] There are several different factors in the densification process that are important to getting the most out of the bioproduct. Among these are “the distribution of pressing forces; parameters affecting the pressing process and their related interactions, ideal material for pressing and their structure and properties, and dependencies between material properties and densification parameters.”[8] Also, because the main sources for wood biomass are wood chips and saw dust, there must be and understanding of their physical properties, including “particle geometry, force interactions between individual particles, and the effect of these “material” properties on the pressing process.”[8] Because of all the different components important for densification, there are standards that must be met which determine the quality of the briquette before it is burnt.[8]

The process of converting biomass into steam for generating energy

Biomass energy uses different sources of biomass such as plant waste and animal waste to make energy. To convert plant waste to bioenergy it is first burned to heat water, which in turn creates steam. The steam creates pressure on a turbine which makes it spin, which then powers a generator creating electricity.[9]

The practice of logging in British Columbia

In 2008, British Columbia’s ‘BC Bioenergy Strategy’ was published, which saw them set goals for bioenergy for the future, while reporting their existing biomass use transparently for the public.[10] With this strategy, their goals included “achieving zero net greenhouse emissions from energy generation, improved air quality, electricity self-sufficiency and increased use of biofuels”.[10] They included several points in relation to the specific use of wood waste for bioenergy not only in the present, but their goals for the future.[10]

Currently, there are two main sources of wood waste biomass in BC. The first one, sustainable forestry accounts for 53% of BC’s total biomass supply and it includes forest residues from logging practices, road cleaning and other forestry activities.[10] The second, Mountain Pine Beetle damaged timber accounts for 34% of BC’s total biomass supply and will be a supply of biomass for approximately 20 years (since the of publication, 2008).[10] The Ministry of Forests and Range began work on wood Biofuel Supply Estimates, evaluate the biomass potential of different regions, and will help power producers in estimating the feasibility of bioenergy opportunities from wood.[10]

A leader in BC of bioenergy is the city of Revelstoke, with an operation in plan since 2005 called ‘The Revelstoke community energy project’ which has “increased energy efficiency, reduces wood waste from sawmills and improves local air quality ”[10]. There are also several different wood pellet bioenergy facilities in British Columbia, located in the cities of Princeton, Kelowna, Armstrong, Williams Lake, Quesnel, Prince George, Vanderhoof, and Houston.[10]  

In the future, BC plans to eliminate the use of beehive burners, which will improve the use of wood waste and lower pollutants. BC also plans to promote the production of wood pellets, facilitate market development opportunities, and improve access to wood fiber feedstocks for forest and energy industries as well as provincial government partners.[10] The province also plans to introduce new technology for a more productive use of wood waste in saw mills and pulp mills and is also working on developing ethanol from wood waste.[10] There is also a program to “support value-added uses for wood residue” called Ethanol BC.[10] This program has funded “research and development of softwood residue-to-ethanol technology by Lignol Innovations”, “advances in wood gasification technology by Nexterra” as well as “fuel pellet design, engineering and emission performance assessments testing wood, agricultural fibre and other feedstocks.”[10]

The impacts of using wood waste for bioenergy in British Columbia

The impacts of wood waste for bioenergy in British Columbia

Pollution emission of biomass vs. fossil fuel

The impact of using wood waste for energy in B.C. has seen a mixed review in recent years. The main process in which wood waste is turned into fuel is the creation of pellets, or compacted wood. Much of B.C.’s pellet production comes from wood mill wastes, industry notes.[11] A major point of controversy is the extent to which any of those pellets come from whole trees cut just for fuel. Studies strongly suggest that generating power by burning whole trees that would otherwise, even dead, lock up carbon for decades to come in a forest, releases more carbon, sooner, than if they were left standing.[11] At present, wood is commonly considered as a carbon-neutral resource. Heavy discussions regarding research have changed the view of the BC government regarding wood biomass, leading it to consider wood as a potentially not CO2 or GHG neutral  if not managed properly, that is, by means of  sustainable practices. However, by using wood waste and wood coming from forests certified SFM (Sustainable Forest Management), UBC (as a public sector organization) avoids further major changing in its GHG emissions as the government is not considering changing protocols for these two types of wood.[11] The only regulations existing today is to report separately the CO2 emission from non- bio sources. If the wood doesn’t come from wood waste or certified SFM forests, its emission could be considered in the future as non-bio emissions, which means that they will count as non-bio CO2 emissions requiring an offset.[11]

Advantages of using wood waste for bioenergy in British Columbia

Carbon dioxide cycle of bioenergy and fossil

There are many benefits to the use of wood waste towards energy production. Wood waste used as a fuel source is a renewable energy that can replace a significant chunk of energy that would otherwise be using coal, oil, or gas. These energy sources are not renewable and only add to pollution. Trees produce oxygen, and if more were planted to use for fuel, there would be an addition of oxygen given, and a significant number less of CO2.[12] Wood waste is also something that is available in most areas of the world, and is easier to find than new sources of fossil fuels, replacing the fossil fuel to a renewable source.[12] Also, the leftover and unused wood waste after a major disturbance can be burned. And by using the wood waste for bioenergy rather than disposing it directly on forest land reduces the risk of a major forest fire in the near future.

Disadvantages of using wood waste for bioenergy in British Columbia

There are some disadvantages to using wood waste as energy. Wood waste may lead to more pollution as plantation farms are resource intensive and the process of harvesting may be more polluting than the energy they are getting out of the trees.[12] More research will be needed as of now the process of harvesting on a large scale is not ecologically sound or cost effective.[12] On the other hand, the process of using wood waste for bioenergy in British Columbia requires investment into new power plants to replace traditional power generators.[13] Most of the power generated in British Columbia is already from a renewable source so that bioenergy would not have significant effects, considering the vast amount of capital needed to produce bioenergy.[14]

Different perspectives on the use of wood waste for bioenergy in British Columbia

Environmental perspectives

Wood waste produced from logging creates fire hazards

For many years, people have been exploiting the timber resources from the forests in British Columbia. The environmental focus is mainly towards the deforestation from the process, ignoring the minor issues about the wood waste produced during the process. The main environmental issue about logging slash is its effect on the forest floor after harvesting. If the logging slash is not properly treated from the process, it would increase the pH of the forest floor, bringing detrimental effects towards the environment.[15]  Also, the logging slash produced during logging could potentially create fire hazards in the forest areas, making the logging slash harmful for the environment.[16] By using the wood waste for bioenergy, people are able to prevent the waste of logging slash produced throughout the process of logging and the production of timber. And by preventing the wasteful disposal of logging slash, the process also produces bioenergy which contributes to emission reductions.[17] Since bioenergy is considered to be renewable, this process favors the protection of the environment. And it could potentially reduce the use of other unrenewable energy sources such as fossil fuel.[18] However, by using the logging slash for other purposes other than disposal onto the forest floor resulted in nutrient losses in the soils.[19] And there would be detrimental effects if the soil is not managed properly after harvesting.

Economical perspectives

Hydroelectricity generating plant in British Columbia

Although the use of logging slash for bioenergy is beneficial for the environment and supported by society, the processes are very expensive compared to the other sources of energy.[20] There are no economic incentives for the logging companies to support the use of logging slash for bioenergy, where they do not benefit directly from this process.[21] Therefore, it is likely that policies regarding the production of bioenergy from wood waste difficult to enforce. This process does not favor the profit of the logging companies, and it could also potentially affect the economy if the policies are forced towards people. However, there are many types of researches about more efficient methods of using wood waste for bioenergy.[22] And the use of logging slash for bioenergy could become economically beneficial in the future.

Social perspectives

In British Columbia, people have always supported environmental protection and the use of renewable energy. Where over 90 percent of energy usage is from renewable sources.[14] Although the economic outcomes of the policies are not favorable towards many people, these outcomes related to environmental issues will favor the majority of society.[23] The social benefit is satisfied in this case, with the loss of benefit from fewer individuals. However, many organizations and campaigns regarding environmental issues do not stress on the use of wood waste. By disregarding this issue, there is limited public awareness of this subject.[24] As a result, there are only minor social impacts on the use of wood waste for bioenergy.

Other alternatives for the use of wood waste

Wood waste could be used to replace timber in furnitures

Using wood waste for bioenergy prevents the logging slash to further damage the environment. However, there are many other alternative uses for wood waste that could also solve this issue. It is disputable that using wood waste for bioenergy is not the most efficient way for its use. One alternative to the use is using wood waste as cement replacing material.[25] By replacing cement with the products of logging slash generated from logging activities reduces its harm towards the environment. Not only is the use of wood waste to replace cement beneficial environmentally, but it is also a cheaper alternative to the use of it for bioenergy.[26] Therefore, this could potentially become a more feasible replacement for the use of wood waste. And there are many other options possible for the alternative use of wood waste, including the use of constructions and furniture.[27] So that people should not be limited to just the use of wood waste as an energy source.

Conclusion and recommendations

Even though there are policies already devised by the government to regulate the disposal and use of logging slash, it is always useful to explore new options for the use of wood residues.[28] The use of wood waste for bioenergy is a promising energy source that could be sustainable for the future. From assessing this issue from many different perspectives, it is evident that bioenergy provides a great option for the use of wood residues. However, there are still many problems related to the use of wood waste for bioenergy, including the economic problems associated with this issue. Therefore, the process of the production of bioenergy should be further developed before it would be considered to be valuable from all perspectives. While the process of generating bioenergy from wood waste should be improved and perfected before it would be used to replace unrenewable sources of energy, there are many other alternatives that one should consider. And the most feasible approach for the use of wood waste is to compromise with other alternative uses of wood waste until there are significant improvements and advancement in the production process of bioenergy.  

References

  1. 1.0 1.1 1.2 Overview of the BC forestry industry. (2015). Retrieved from: https://www.bccpa.ca/CpaBc/media/CPABC/News_Events_Publications/Publications/Industry_Update/industry_update_fall_2015.pdf
  2. "Bioenergy". Bioenergy. International Renewable Energy Agency.
  3. "Bioenergy Research and Development at CanmetENERGY". Bioenergy Systems. Natural Resources Canada. 2018.
  4. 4.0 4.1 Bradburn, K. (2014). 2014 Canbio Report on the Status of Bioenergy in Canada. Retrieved from: http://www.fpac.ca/publications/2014_CanBio_Report.pdf
  5. BC Bioenergy Strategy: Growing Our Natural Energy Advantage. British Columbia Ministry of Energy, Mines and Petroleum Resources, 2009. Retrieved from:https://www2.gov.bc.ca/assets/gov/farming-natural-resources-and-industry/electricity-alternative-energy/bc_bioenergy_strategy.pdf
  6. "Bioenergy and biofuels". Bioenergy. International Energy Agency.
  7. "Advantages and disadvantages of bioenergy". Advantages and disadvantages of bioenergy. Origin Energy.
  8. 8.0 8.1 8.2 8.3 8.4 8.5 Krizan, Peter (2015). The Densification Process of Wood Waste. Warsaw/Berlin: De Gruyter Open Ltd. Retrieved from: https://www.degruyter.com/viewbooktoc/product/458852
  9. "Renewable Biomass Energy - Waste not, want not!". Biomass Energy. Green Mountain Energy Company. 2019.
  10. 10.00 10.01 10.02 10.03 10.04 10.05 10.06 10.07 10.08 10.09 10.10 10.11 BC Bioenergy Strategy. (2008). Retrieved from https://www2.gov.bc.ca/assets/gov/farming-natural-resources-and-industry/electricity-alternative-energy/bc_bioenergy_strategy.pdf
  11. 11.0 11.1 11.2 11.3 Robert, M. Sketchy Claims Inflate BC’s Wood Energy Exports" The Tyee. "https://thetyee.ca/News/2014/04/24/BC-Wood-Energy-Exports/, 2014,04,24
  12. 12.0 12.1 12.2 12.3 Courtney ,M, "Biomass Advantages and Disadvantages." Syntech. https://www.syntechbioenergy.com/blog/biomass-advantages-disadvantages
  13. Ravindranath, N. H., Balachandra, P., Dasappa, S., & Rao, K. U. (2006). Bioenergy technologies for carbon abatement. Biomass and Bioenergy, 30(10), 826-837. Retrieved from: https://www.sciencedirect.com/science/article/pii/S0961953406000535
  14. 14.0 14.1 Keeney, R. L., & McDaniels, T. L. (1992). Value-focused thinking about strategic decisions at BC Hydro. Interfaces, 22(6), 94-109. Retrieved from: https://pubsonline.informs.org/doi/abs/10.1287/inte.22.6.94
  15. Staaf, H., & Olsson, B. A. (1991). Acidity in four coniferous forest soils after different harvesting regimes of logging slash. Scandinavian Journal of Forest Research, 6(1-4), 19-29.Retrieved from: https://www.tandfonline.com/doi/abs/10.1080/02827589109382643
  16. Pyne, S. J. (1984). Introduction to wildland fire. Fire management in the United States. John Wiley & Sons. Retrieved from: https://www.cabdirect.org/cabdirect/abstract/19850601055
  17. Hawley, L. F. (1952). Combustion of wood. Wood Chemistry, LE Wise, editor, 671-679. Retrieved from: https://www.tandfonline.com/doi/abs/10.3155/1047-3289.61.1.63
  18. Fergusson, G. J. (1958). Reduction of atmospheric radiocarbon concentration by fossil fuel carbon dioxide and the mean life of carbon dioxide in the atmosphere. Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences, 243(1235), 561-574. Retrived from: https://royalsocietypublishing.org/doi/abs/10.1098/rspa.1958.0021
  19. Brown, G. W., Gahler, A. R., & Marston, R. B. (1973). Nutrient losses after clear‐cut logging and slash burning in the Oregon Coast Range. Water Resources Research, 9(5), 1450-1453. Retrieved from: https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/WR009i005p01450
  20. Wahlund, B., Yan, J., & Westermark, M. (2004). Increasing biomass utilisation in energy systems: A comparative study of CO2 reduction and cost for different bioenergy processing options. Biomass and bioenergy, 26(6), 531-544. Retrieved from: https://www.sciencedirect.com/science/article/pii/S0961953403001661
  21. Niquidet, K., Stennes, B., & van Kooten, G. C. (2012). Bioenergy from mountain pine beetle timber and forest residuals: a cost analysis. Canadian Journal of Agricultural Economics/Revue canadienne d'agroeconomie, 60(2), 195-210. Retrieved from: https://onlinelibrary.wiley.com/doi/full/10.1111/j.1744-7976.2012.01246.x
  22. Kalt, G., & Kranzl, L. (2011). Assessing the economic efficiency of bioenergy technologies in climate mitigation and fossil fuel replacement in Austria using a techno-economic approach. Applied Energy, 88(11), 3665-3684. Retrieved from: https://www.sciencedirect.com/science/article/pii/S0306261911001711
  23. Elliott, D. (2004). Energy, society and environment. Routledge. Retrieved from: https://content.taylorfrancis.com/books/download?dac=C2009-0-25286-4&isbn=9781134407026&format=googlePreviewPdf
  24. Sweet, H. R., & Fetrow, R. H. (1975). Ground‐Water Pollution by Wood Waste Disposal. Groundwater, 13(2), 227-231. Retrieved from: https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1745-6584.1975.tb03080.x
  25. Cheah, C. B., & Ramli, M. (2011). The implementation of wood waste ash as a partial cement replacement material in the production of structural grade concrete and mortar: An overview. Resources, Conservation and Recycling, 55(7), 669-685.Retrieved from: https://www.sciencedirect.com/science/article/pii/S0921344911000231
  26. Udoeyo, F. F., Inyang, H., Young, D. T., & Oparadu, E. E. (2006). Potential of wood waste ash as an additive in concrete. Journal of materials in civil engineering, 18(4), 605-611.Retrieved from: https://ascelibrary.org/doi/abs/10.1061/(ASCE)0899-1561(2006)18:4(605)
  27. Daian, G., & Ozarska, B. (2009). Wood waste management practices and strategies to increase sustainability standards in the Australian wooden furniture manufacturing sector. Journal of Cleaner Production, 17(17), 1594-1602. Retrieved from: https://www.sciencedirect.com/science/article/pii/S0959652609002212
  28. Demirbas, A. (2008). Biofuels sources, biofuel policy, biofuel economy and global biofuel projections. Energy conversion and management, 49(8), 2106-2116.Retrieved from: https://www.sciencedirect.com/science/article/pii/S0196890408000770


Seekiefer (Pinus halepensis) 9months-fromtop.jpg
This conservation resource was created by Will. It is shared under a CC-BY 4.0 International License.