Renewable Energy Handbook 2010 - Department of Finance - The ...

Wood represents 3.1 per cent of Australia’s totalprimary energy consumption. Most of the heat energythat is produced is consumed as fi rewood in theresidential sector. The remaining heat energy is usedin the wood products, paper and food industries.Western Australia has several sources of bioenergyresources that could be developed further:Forestry and tree crop resources include residues·from forestry plantations and the potential newwoody crops for wheat belt agriculture, such as oilmallee; agricultural crops which have high starch/sugar content (such as cereals and sugar cane),or herbaceous annual crops which have high oilcontent (sunfl owers or canola). The waste fromthese crops can be used in the production oftransport fuels (ethanol and biodiesel).Animal wastes, classifi ed as wet wastes, can be·ideal feedstocks for anaerobic digestion. The mostcommonly used animal wastes are manures frompigs, chickens and cattle (in feedlots). As theseanimals are reared in confi ned spaces, and thusgenerate a large amount of waste in a small area,these resources are ideal for bioenergy generation.Meat processing and abattoir wastes are alsopotential resources, for example tallow can beused as a feedstock for biodiesel.Industrial wastes – the food industry produces a·large number of residues and by-products that canbe used as bioenergy energy sources. Dry wastesinclude peelings and scraps from fruit andvegetables, food that does not meet quality controlstandards, pulp and fi bre from sugar and starchextraction, fi lter sludges and coffee grounds.···OFFICE OF ENERGYRENEWABLE ENERGY HANDBOOK 2010Dry wastes may be suitable for direct combustion,gasifi cation or pyrolysis. Wet industrial wastestreams are generated by washing meat, fruit andvegetables, blanching fruit and vegetables,pre-cooking meats, poultry and fi sh, cleaning andprocessing operations and wine making. Thesewaste waters contain sugars, starches and otherdissolved and solid organic matter. The potentialexists for these industrial wastes to beanaerobically digested to produce biogas,or fermented to produce ethanol.Municipal Solid (Green) Waste (MSW) can beconverted into energy by direct combustion,gasifi cation or through anaerobic digestionoccurring when the material is disposed in alandfi ll. In Western Australia there are a numberof landfi ll gas plants. The gas produced at thesesites through the anaerobic decomposition ofMSW (approximately 50 per cent methane and50 per cent carbon dioxide) is collected from thestored material and scrubbed before feeding intointernal combustion engines or gas turbines togenerate heat and power.Sewage Energy can be extracted from sewageusing anaerobic digestion to produce biogas.The sewage sludge that remains can then becombusted or undergo gasifi cation or pyrolysisto produce more biogas and ‘bio-oil’.Table 7 provides some current examples ofbioenergy projects in Western Australia.TABLE 7. EXISTING AND PROPOSEDBIOENERGY PROJECTS IN WESTERN AUSTRALIA57RENEWABLE ENERGY IN WESTERN AUSTRALIAPROJECTPROPONENTCAPITAL(MW)START DATELandfi ll gas (produced from the anaerobicdecomposition of commercial, industrial anddomestic wastes) at Redhill, Canning Vale, MtClaremont, Kalamunda and Tamala ParkLandfi ll Gas and Power12.3 MW(total capacity)1995 – 2004Woodman Point Wastewater Treatment Plant: Water Corporation 1.8 1998Manjimup Bioenergy power facility Western Australian Bioenergy 40 Late 2010Perth metropolitan (2 sites) landfi ll gas project Landfi ll Management Services 4.4 –Perth metropolitan (1 site) landfi ll gas project Waste Gas Resources 2.1 –Landfi ll gas extraction and generation site:AGL Energy Services Pty LtdGosnellsRockingham2.11.62003