Parratt & Associates Scoping Biorefineries: Temperate Biomass Value Chains

Chapter 3. Biomass Assessments in Temperate Australia

Biomass, as covered in this report, is defined as lignocellulosic or second generation feedstocks (incorporating crop residues and timber) – that is, biomass with minimal impact on food supplies for animals and humans. Biomass types include crop stubble; low-value logs and harvest residues from hardwood and softwood plantations and native forests; processing residues from sawmills; and biomass produced from crop residues and timber plantings. These categories are considered to be the major potential sources of temperate lignocellulosic biomass from Australia that could be used for energy or fuel production⁴³. They are therefore likely to be key sources for any future biorefinery. Feedstock availability and cost is recognised as a potential key factor for Australian production of bioelectricity, biofuels or other bioproducts. In order to assess the economic viability of a future biorefinery, it is crucial to estimate the potential availability of feedstocks and their likely cost.

A number of regional and national studies estimate the potential production of various biomass feedstocks for biofuel or bioenergy. However, few contain original data, and they often fail to specify whether the reported results refer to wet or dry tonnes, or the assumed moisture content or density of the biomass types considered. Currently available national assessments include the Clean Energy Council’s appraisal of biomass resources from agriculture, urban waste streams and energy crops⁴⁴; Geosciences Australia’s review of current and potential production of bioenergy from existing agricultural, forestry and urban biomass⁴⁵; and a CSIRO study of the potential production of biofuel from current and potential future biomass resources⁴⁶. In addition, the Department of the Environment, Water, Heritage and the Arts has developed an online bioenergy atlas of Australia⁴⁷; however, it contains no data for biomass production. Regional assessments include an assessment of biomass waste streams for bioenergy for the Central Highlands of Victoria⁴⁸, and an analysis of biomass, nutrient and potential energy recovery for the Murrumbidgee Irrigation Area in NSW⁴⁹.

There is currently a lack of reliable state-based or national-based estimates of availability and cost of different biomass types. In this report, we provide indicative estimates of the amount and cost of potential biomass available, both currently and into the future, for all temperate Australian states (i.e. excluding Queensland, Northern Territory and north-western Australia). These estimates are derived from ABARE figures for sawlog, pulp log and grain production; assumptions regarding residue fractions; modelled predictions of future growth of existing and new plantations; and industry surveys. They should therefore be viewed as indicative only, and should not be taken as definitive quantities or prices.

3.1 National assessments

The biomass resource appraisal by the Clean Energy Council (CEC) estimated the amount of biomass potentially available for bioenergy production in the following categories;

• 
  agricultural-related wastes;
  
• 
  sugarcane;
  
• 
  timber-related wastes;
  
• 
  energy crops;
  
• 
  landfill and sewerage gas;
  
• 
  sewerage gas; and
  
• 
  urban biomass (including urban timber wastes).
  

This study has undertaken an overall analysis of various sources of data on biomass. Results from this assessment are summarised in Table 3-1a Agriculture, Table 3-1b Forestry, Table 3-1c Energy Crops, Table 3-1d Waste Streams and Table 3-1e Total Assessment, together with sources of the data. The sources used in the CEC report are often not primary references, and some sources are not listed at all. This can result in confusion and a lack of substantiation. For example, the figure for crop stubble⁵⁰ was actually obtained from previous conference proceedings⁵¹. Further, in terms of potential energy crops, biomass from mallee systems (of which at least 13,000 ha have already been planted⁵²) are discounted as being considered commercially unviable prior to 2020. Also, Fibrecell Australia estimates that a virtually untested potential species called enercane (Arundo donax) could provide 200,000 tonnes of biomass from currently non-arable land.

The Clean Energy Council study estimates that 48 Mt/y biomass could be available nationally. This consists of 24 Mt/y from crop stubble, 9 Mt/y from bagasse and cane trash, 9 Mt/y from forest and sawmill residues, 6 Mt/y from urban and municipal waste and 0.2 Mt/y from energy crops and woody weeds. The report indicated that this biomass would be sufficient to produce approximately 7.8TWh/y electricity in 2020 rising to 63.4TWh in 2050. In 2008-09, renewable (non-hydro) based electricity production was 2.5GWe capacity or 4.5% of the 56 Gigawatt (GWe) capacity producing 249TWh/y.

In 2010, Geoscience Australia⁵³ released a report reviewing the different resources available in Australia for the production of energy. The document included a chapter on bioenergy that focused on Australia’s current bioenergy market, comparing it to worldwide bioenergy markets. While the report cited the Clean Energy Council⁵⁴ figures for sugarcane bagasse and cane trash, it did not indicate where the data for other biomass resources were sourced⁵⁵. However, these figures are almost identical to those in the Clean Energy Council report, suggesting that this was the primary source (Table 3-1c). In fact, the only differences between the two sets of figures are that the Geoscience Australia figures – contrary to the Clean Energy Council report – assumes that mallee energy plantings will be economically viable prior to 2020, while enercane plantings will not.

A third National assessment of biomass resources was produced by CSIRO for Rural Industries Research Development Corporation (RIRDC) in 2007⁵⁶. This report outlined the prospects for biofuel in Australia, and highlighted issues surrounding the emerging biofuel industry. It featured a number of scenarios based around biomass feedstock and the potential production of biofuel, including the current production (i.e. based on 1 generation feedstocks) and potential future production (i.e. based on 2^stnd generation feedstocks). Scenario 1 allowed for the total amount of Australian feedstock production to be converted to biofuel. Scenario 2 allowed for the conversion of only the export fraction of biomass feedstock. The authors point to the variability in both the data and the resource base, particularly in assessing the potential level of future biomass production. The report reviews the reasons for this variability, plus the impacts on other industries and sustainability issues related to the use of biomass feedstocks for biofuel production.

This last assessment estimated the potential total amount of lignocellulosic biomass produced across Australia to be 110–219 Mt/y with a maximum of 49–148 Mt/y (approx 50%) likely to be available for biofuel production in the future. The latter higher figure included a large contribution from mallee energy plantings (2–100 Mt/y) in addition to the 31 Mt/y from agricultural residues; 16 Mt/y in the form of logs and residues from native forests, plantations and sawmills; and 1 Mt/y from municipal and industrial waste. These feedstocks could contribute 13–45 GL/y ethanol, potentially replacing between 10–140% of Australia’s 2004–5 petrol usage. The range of values reflects the variable estimates of the scale of biomass.

While many of the figures used in the report are sourced from other publications, others, such as those for crop or forest residues, are based on unpublished estimates from models. The estimated range for the potential contribution of biomass from mallee energy plantings in particular is based on limited data, and does not account for potential displacement of cropland or grazing land. This figure should therefore be considered highly speculative.

Table 3-1: Estimates of biomass availability across Australia for energy or fuel

Table 3 1a Agriculture
^57^58^59Biomass type		Clean Energy Council			Geoscience Australia								CSIRO
		Biomass			Biomass					Electricity			Biomass							Ethanol
										2020		2050	Total					Available
		Mt/y			Mt/y					TWh/y		TWh/y	Mt/y					Mt/y		GL/y
^60^61Stubble residues		24			24		^74			0		47	53					30		9.0
Sugarcane
^62	- Bagasse	5.0			5.0		^74			3.0		4.6	NDA					NDA		NDA
	- Cane trash	4.0	^NR		4.0		^74			0.2		3.2	NDA					NDA		NDA
^63Grassland		NDA			NDA					NDA		NDA	10-20					0.5-1.0		0.15-0.30
Total Agriculture		33			33					3		5.5	63-73					30.5-31		9.15-9.3

Table 3 1b Forestry
^64^65^66Biomass type				Clean Energy Council		Geoscience Australia				CSIRO
				Biomass		Biomass		Electricity		Biomass			Ethanol
								2020	2050	Total		Available
				Mt/y		Mt/y		TWh/y	TWh/y	Mt/y		Mt/y	GL/y
Current
^67	Logs			NDA		NDAA		NDA	NDA	14		4.7	1.4
	Forest Residues
^68^69		- Native		2.2		2.2	^74	0.6	1.1	2.7		1.35	0.15-0.50
^70		- Plantation		3.8	^79	3.8	^74	1.1	2.0	2.1		1.05	0.25
^71^72		- Sawmill		2.8		2.8	^74	0.8	1.4	1.3		0.65	0.35
		Total		8.8		8.8		2.4	4.6	6.1		3.1	0.8-1.1
Future additional
			Native	NDA		NDA		NDA	NDA	2.5		2.5	0.25-1.30
^73			Plantation	NDA		NDA		NDA	NDA	14		4.7	1.0
^74Firewood				NDA		NDA		NDA	NDA	5		0.5	0.1-0.55
Total Forestry				8.8		8.8		2.4	4.6	41.6		15.5	3.6-5.4

Table 3 1c Energy crops
^75^76^77Biomass type	Clean Energy Council		Geoscience Australia				CSIRO
	Biomass		Biomass		Electricity		Biomass			Ethanol
					2020	2050	Total		Available
	Mt/y		Mt/y		TWh/y	TWh/y	Mt/y		Mt/y	GL/y
^78^79^80^81Mallee	0		?	^74	0.11	0.48	2-100	^,,	2-100	0.4-30
^82Enercane	0.2		0	^74	0	0	NDA		NDA	NDA
^83Woody weeds	0.04		0.04	^74	0.083	0.02	NDA		NDA	NDA
Oilseed trees	NDA		NDA		NDA	NDA	?		?	?
Algae	NDA		0	^74	0	0	?		?	?
Total Energy Crops	0.24		0.04		0.20	0.50	2-100		2–100	0.4-30

Table 3 1d Waste streams
^84^85^86Biomass type	Clean Energy Council		Geoscience Australia				CSIRO
	Biomass		Biomass		Electricity		Biomass			Ethanol
					2020	2050	Total		Available
	Mt/y		Mt/y		TWh/y	TWh/y	Mt/y		Mt/y	GL/y
^87^88Wood and timber	1.6	^,	1.6	^74	0.30	1.37	NDA		NDA	NDA
Paper and cardboard	2.3	^83,84	2.3	^74	0.04	1.74	NDA		NDA	NDA
Urban and garden	2.3	^83,84	2.3	^74	0.12	0.46	NDA		NDA	NDA
^89Total Waste streams	6.2		6.2		0.45	3.57	3.3-4	^79,	1.1-1.3	0.20-0.36

Table 3 1e Total Assessment
^90^91^92Biomass type	Clean Energy Council		Geoscience Australia					CSIRO
	Biomass		Biomass		Electricity			Biomass				Ethanol
					2020		2050	Total		Available
	Mt/y		Mt/y		TWh/y		TWh/y	Mt/y		Mt/y		GL/y
Total Agriculture	33		33		3		5.5	63-73		30.5-31		9.15-9.3
Total Forestry	8.8		8.8		2.4		4.6	41.6		15.5		3.6-5.4
Total Energy Crops	0.24		0.04		0.20		0.50	2-100		2–100		0.4-30
^93Total Waste streams	6.2		6.2		0.45		3.57	3.3-4 ^79,		1.1-1.3		0.20-0.36
Total Assessment	48.2		48.0		6.3		63.4	110-219		49-148		13-45

NDA: No data available; NR: No reference provided.

None of the reports reviewed here attempted to provide a detailed regional or state-based breakdowns of current or potential biomass resources. While the reports are useful in providing an indication of the potential scale of a biobased industry at a national level, they are practically useless for showing prospective regions for locating a plant or the amount of resource available in a specific region. Further, although a crude effort has been made to show the potential resource availability, there is no data on the likely cost of producing or transporting the feedstock. The reports thus provide no way of assessing the potential economics of such an industry, or even of assessing which feedstocks might be the most promising.