Greenhouse Gas Emissions and Renewable Energy in Alberta Why are Greenhouse Gas Emissions Important? Over the last century, modern industry and lifestyles have rapidly increased amounts of greenhouse gas (GHG) in the earth s atmosphere. Most scientists who study this topic believe that increased GHG amounts are causing the climate to change. Changes in climate are expected to lead to more severe weather events, such as prolonged droughts and flooding, with associated impacts that may include reduced availability of quality water supplies. Canada has committed to reducing GHG emissions to 17% below 2005 levels by 2020 and 30% below 2005 levels by 2030. Alberta has also made its own commitments to reduce emissions and was the first province to design rules for cutting GHGs. Provinces and territories have been taking steps to address climate change according to their specific circumstances. Businesses and individuals are also reducing emissions by using resources more efficiently and adopting new, cleaner technologies. Alberta s agricultural industry already has many beneficial management practices that can reduce GHG emissions and capture and store carbon. By showing leadership and taking initiative, farmers and ranchers in Alberta can remain competitive, increase efficiencies, adapt to climate change and may be able to capture new opportunities in emerging environmental markets. Fossil Fuel Energy in Agriculture Alberta s economy is largely based on fossil fuels and GHGs are emitted when fossil fuels are burned. Comparing Alberta s various industry sectors, the majority of Alberta s GHG emissions originate from the energy sector. In 2013, Alberta s agricultural industry accounted for approximately 8 % of the province s total GHG emissions, while the oil sands (22%), other oil and gas (24%), electricity (17%), and transportation (11%) sectors accounted for 74% (Alberta Environment and Parks, 2014). What is Renewable Energy? Renewable energy is generated from sources that are replenished in nature at a sufficient rate that they can be used by humans indefinitely. Renewable energy technologies convert renewable resources into forms of energy that can complement or replace conventional energy sources such as fossil fuels into forms of energy with significantly reduced carbon dioxide emissions. Wind, solar, earth energy systems, small scale hydro and biomass (straw, wood, corn) are all sources of renewable energy. Table 1 outlines the various sources of energy in Alberta relative to fossil fuel soures (coal and natural gas), as well as costs and rates of emissions. Ongoing research and development has made many renewable technologies economical, reliable, and environmentally friendly. However, renewable energy technologies are site specific, and what works well on one farm may not work on another (e.g. small scale hydro requires a farm with a stream running through it). Greenhouse Gas Emissions Wind, solar, and small-scale hydro systems have zero GHG emissions. Biomass sources of energy are considered GHG neutral because the carbon dioxide (CO2) generated in producing energy is compensated for by the CO2 used by the growing crop.
Table 1. Alberta generation costs and carbon dioxide equivalents (CO2e) emissions by technology Technology Cents/kWh* Tonnes CO2e /MWh** Coal, with Carbon Capture and Storage (CCS) 23.7 0.11 Coal, without CCS 4*** 0.76 Natural gas, simple cycle 11 0.37 Natural gas, combined cycle 8.2 0.37 Cogeneration 6.9 to 10.6 0.37 Wind 8.9 0 Hydro 10.5 0 PV solar 17.6 0 * AESO Long Term Outlook 2014 ** Source: IPCC 2005, MWh = Megawatt hour *** Aydin et al. 2013 Wind Wind turbines capture wind energy and convert it to electricity. Wind energy systems range greatly in capacity, from small, stand-alone off-grid systems to utility-scale towers that contribute to the provincial power grid. Wind power systems require an average annual wind speed greater than 15 kilometres per hour. Alberta is endowed with abundant wind energy resources (Table 2). In Alberta, wind energy currently has over 1,100 megawatts (MW) connected to the grid or about seven percent of installed capacity (Alberta Energy, 2014). This is enough to serve close to half a million houses. Table 2. Wind generation capacity in Alberta. Value Units Hours in the year 8760 hours Capacity factor 0.34 % Capacity of generating unit 1,100,000 kw Electricity per year 3,276,240,000 kwh Average Alberta residence electricity demand per year 7,200 kwh/year Number of Alberta houses 455,033 Solar There are three types of solar energy systems that can be used to generate heat or electricity: Passive solar systems - collect and store solar energy and distribute it by natural processes such as convection and radiation. Active solar systems - use solar collectors to heat water or air, and a pump to circulate it throughout the building. A typical system will reduce the need for conventional water heating by about twothirds. Dairy, swine and poultry producers, as well as aquaculture operations, are examples of agricultural businesses using solar systems in Canada.
Photovoltaic systems - convert sunlight directly into electricity. Photovoltaic arrays (10 to 20 PV modules, each made up of approximately 40 cells) can provide enough power for a household. For large applications, hundreds of arrays can be interconnected to form a single PV system. Earth energy systems Earth energy systems can provide heating in winter, cooling in summer and year-round hot water for home use. These systems use heat pumps to move heat between the earth and buildings as needed. Heat pumps cost about twice as much as conventional heating systems to install, but on average the operating cost is approximately two-thirds less than traditional systems. More than 30,000 heat pumps or "earth energy" installations in Canada are being used in residential, commercial, institutional and industrial applications. They are considered to be the most energy-efficient, environmentally clean and costeffective heating systems available. Small-scale hydroelectric power Small-scale hydroelectric power technologies use free flowing water to produce electricity. Most micro hydros are run-of-stream systems that divert water through a pipe or channel. The water is directed through a turbine and then allowed to flow back to the river or creek. Because they typically do not require large storage dams, they can be sited, built and operated with minimal environmental impact. Biomass Biomass resources are any plant-derived organic matter available on a renewable basis. This includes forestry and agricultural crops, in addition to animal, food-processing, and municipal wastes. Table 3 outlines the relative effectiveness of a range of biomass feedstocks relative to fossil fuels. There are four ways in which biomass is converted into energy: Incineration - the thermal conversion of biomass into heat energy and ash through complete combustion. Gasification - the conversion of biomass into gases (carbon monoxide and hydrogen) at high temperatures with a controlled amount of oxygen and/or steam. Pyrolysis - the decomposition of biomass in the absence of air and presence of extreme heat, to produce a higher-carbon fuel product Anearobic Digestion the decomposition of biomass in the absence of oxygen to produce energy rich gas. Agriculture operations can benefit from the use of biomass as an energy source because many biomass resources can easily be produced locally and they can be used to produce on-farm energy or sold to producers of bio-energy products. However, for biomass resources to be renewable, sustainable cropping practices are necessary. It is also important to recognize that food crops diverted to produce energy decrease food production for human and animal consumption. Wood Burning wood instead of natural gas or propane can substantially lower heating costs if it is readily available. Wood is more labour-intensive than fossil fuels, which must be taken into account when doing cost comparisons. Depending on the efficiency of the stove or furnace, burning wood emits unburned hydrocarbons, smoke and entrained ash at varying levels. Straw Shredded, loose, and densified straw (pellets, briquettes, cubes, straw logs), square bales and round bales can be burned to heat water, buildings or dry grain. A straw burning system is economical in meeting demands for large heat load. Most bale-burning boilers are about 40 percent efficient. However, the availability of straw varies considerably between regions and between years due to variations in climate and livestock requirements for feed and bedding. Transportation costs from fields to biomass facilities must be taken into account. Sufficient straw must also remain on fields to return crop nutrients and
protect soil from erosion by wind and water. Alberta Agriculture and Forestry recommends that 30 percent of the soil surface be covered by crop residue to prevent soil erosion. Switchgrass Switchgrass (Panicum virgatum) is a native perennial grass that once dominated the North American tallgrass prairie. It grows with minimal inputs of water and fertilizer, can grow on marginal lands and does not require specialized production equipment. A switchgrass plantation can last from 5 to 15 years. The grass is harvested annually, then chopped and pelleted for use in specialized stoves and furnaces. Switchgrass is suitable for production in some parts of Alberta. Grain Grains such as wheat are starch crops that can either be used as a heating fuel or converted to bioethanol. However, grains may not be a good fuel source because it diverts needed foodstuffs, requires large fertilizer, herbicide and pesticide inputs for production, and has a high ash content, making it difficult to burn. Biogas Biogas is generated by the anaerobic (no oxygen) digestion of organic material such as manures and municipal wastes. Biogas can be burned to produce heat, electricity or both. Liquid manure systems work best for anaerobic digestion. The installation and operation of an anaerobic digester requires considerable monetary and manpower investments. The feasibility of anaerobic digestors depends on type of livestock, type of manure management system, and heat and electricity requirements. The feasibility of digestors in terms of cost and continuity of feedstock supply requires careful evaluation. Biofuels Biofuels include biogas, alcohols, ethers, esters and other chemicals made from biomass resources. Biofuels can be used as a supplement or an alternative to fossil fuel to produce electricity, heat and/or transportation fuel. In the short-term, biofuels can be used as blending agents to dilute CO2 emissions from fossil-based fuels. In the long-term, technological advances are expected to allow greater use of biofuels in vehicles. Bioethanol (fuel alcohol) is made from starch (grain crops, corn); sugar (sugar beet or sugar cane); and, although still in the preliminary stages, from cellulose (wood, straw, grass or municipal solid waste). Bioethanol is widely used in Brazil and the USA today. Ethanol-blended fuels such as E85 (85 percent ethanol and 15 percent gasoline) can reduce net greenhouse gas emissions by as much as 37 percent, and E10 (10 percent ethanol and 90 percent gasoline) can reduce net greenhouse gas emissions by almost four percent. Biodiesel is manufactured from most vegetable oils such as canola or soybean, animal fats, recycled grease, as well as low quality oilseeds and tall oil produced from wood pulp waste. Biodiesel can be blended with conventional diesel fuel or used straight (100 percent biodiesel).it is typically added to petroleum diesel in 20 percent blends (B20) for diesel engines and is a direct fuel substitute for #2 petroleum diesel. Biodiesel used as a fuel or additive requires little or no engine modification and biodiesel fueled engines deliver similar mileage, torque and horsepower. Compared to fossil fuels, is that it degrades quickly in the environment and is nontoxic. The combination of improved technological efficiencies, scientific advances, increased environmental awareness and environmental protection regulations have turned biomass conversion into a cleaner, more efficient process. As the biomass energy market grows, so will the market for biomass resources, which may provide farms with another stream of income.
Table 3. A comparison of Lower Heat Values (LHV) for burning different energy sources. Fuel Lower Heat Values BTU/lb MJ/kg Natural Gas 22865 53.18 Propane 19940 46.37 Gasoline 18831 43.80 Diesel (#2) 18401 42.80 Biodiesel 16251 37.80 Fuel Oil (#1) 15910 37.00 Ethanol 11479 26.70 Coal 10318 24.00 Coal (sub-bituminous) 9000 20.93 Flax straw (dry) 8587 19.97 Wood Pellets 8512 19.80 Wheat straw (dry) 7680 17.86 Corn straw (dry) * 7540 17.50 Shelled corn (15% moisture) * 7000 16.20 Flax straw (20% moisture) 6635 15.43 Wood (15% moisture) 6450 15.00 Wheat straw (20% moisture) 5908 13.74 Biogas 55159 17.25 PAMI Research Update #719. 1995. *OMAFRA Agdex #111.768. 1997 Incentives for Energy Improvements In Alberta, carbon credits can also be created from voluntary management improvements that have a sound science basis for lower greenhouse gas emissions, are above and beyond business as usual, and can be verified by independent third parties. Companies who are regulated under Alberta s Specified Gas Emitters Regulation (2002) can use carbon credits as way to meet their requirement to reduce greenhouse gas emission intensities each year. There are a number of carbon offset protocols that provide incentives to support the generation of renewable energy. These protocols outline the science, policy and verification basis for management improvements that are eligible to create carbon credits for sale to regulated companies. More information about agricultural carbon offsets is available at: www.agricuture.alberta.ca/agcarbonoffsets. Summary Renewable energy can complement or replace conventional and reduce GHG emissions at the same time. Wind, solar, and small-scale hydro systems have zero GHG emissions. Biomass resources are considered GHG neutral because the CO2 generated during combustion is offset by the CO2 used by the growing biomass crop. Reducing emissions can improve the industry s production efficiencies, conserve soil and water resources, and help slow global warming. Sources Alberta Electric Systems Operator. 2014. AESO 2014 Long-term Outlook Alberta Environment and Parks. 2014. Climate Leadership Discussion Document. 62pp. Available at: http://www.alberta.ca/albertacode/images/climate-leadership-discussion-document.pdf
Alberta Energy, 2014. Electricity Statistics. Available at: http://www.energy.alberta.ca/electricity/682.asp Aydin, O. and Graves, F. and Celbbi, M. 2013. Coal Plant Retirements Feedback Effects on Wholesale Electricity Prices. The Brattle Group IPCC, 2005. IPCC Special Report on Carbon Dioxide Capture and Storage. Prepared by Working Group III of the Intergovernmental Panel on Climate Change [Metz, B., O. Davidson, H. C. de Coninck, M. Loos, and L. A. Meyer (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, 442 pp. Kralovic and Mutysheva. 2006. The Role of Renewable Energy in Alberta s Energy Future. Canadian Energy Research Institute, Calgary.