After the oil crises of the 1970s, there was great interest in Australia in the development of biomass as an alternative energy source. This study was initiated to try to define the market potential of biomass as an alternative energy source and to develop a strategic plan for the future of the industry.
EXECUTIVE SUMMARY
INTRODUCTION
In addition to the main body of the report, there are seven appendices which mainly comprise the detailed reports of individual consultants that support this part of the report. These appendices allow the reader to gain much more detailed knowledge and analysis, even though the main report is written as a stand-alone document.
ENERGY MARKET ASSESSMENT
There are already a number of state and federal subsidies in the US for ethanol used as an automotive fuel. During this period there has also been steady growth in estimates of the world's total oil resources, undermining the use of such estimates as measures of scarcity of production potential.
AUSTRALIAN ENERGY MARKETS
The other main applications are the production of wood and related products and paper production. In the context of the remainder of this research, Australian energy prices used are those of mid-1994.
RESOURCES ANALYSIS AND DISTRIBUTION
- Oilseed Crops
- Lignocellulose
Canning produces pineapple waste consisting of skin and pith (the tops are left in the field during harvest). Available food crop residues account for 30 million of the 54 million tonnes of crop residues produced in Australia.
CONVERSION TECHNOLOGIES
A large part of the work in reviewing the major thermal and biochemical technologies was to reliably identify their capital and operating costs. Where possible, information on capital and operating costs is obtained from plants that have been built and are commercial. Care is exercised where it has not been possible to follow up on the best available estimates derived from pilot plants and engineering studies for energy technologies.
Representative examples of each technology were selected and used to document the required data on capital and operating costs, process inputs and outputs, major waste streams, and overall process energy balances.
CONVERSION TECHNOLOGY OPTIONS .1 Direct Combustion
- Fuel Methanol
- Fuel Ethanol
- Anaerobic Digestion
- Anaerobic Digestion of MSW
- Oxygenates
The Hydrocarb process, originally developed by Brookhaven National Laboratories, is now being developed by Hydrocarb Corp in the US. Companies in the US are reportedly building demonstration plants as a prelude to the commercialization phase. Organizations at the forefront of this field include Iogen and StakeTech in Canada (steam explosion pathway) and the National Renewable Energy Laboratory (enzyme hydrolysis and fermentation), the Tennessee Valley Authority (dilute and concentrated acid hydrolysis), and Arkenol in the USA.
The oil can be pressed from the seeds, leaving a 5-7% oil in the remaining flour.
SUMMARY
Pyrolysis is the conversion of biomass into gases or liquids by heating in the absence of oxygen. Other commercialization activities include a number of projects in the 18-90MWE range using a range of biomass gasification technologies integrated with gas turbines. Technology for ethanol production from lignocellulosic biomass is under development and some companies claim to be in the commercialization phase.
Organizations at the forefront of ethanol recovery in the US are Stake Tech (steam explosion route), Tennessee Valley Authority (dilute and concentrated acid routes), National Renewable Energy Laboratories (saccharification and single-stage fermentation enzyme) and Arkenol (acid pathway).
SYSTEMS SELECTION
SYSTEMS SELECTION 5.1 INTRODUCTION
BIOMASS ENERGY COSTS .1 Introduction
- Methodology
- Biomass Energy Costs
Using capacity and operating cost estimates given for the Australian small-scale technology being developed by BES T, electricity costs are expected to be in the range of 0.5 M W e to 4 M W e with between 9 and 3 cents per Kwhe. Products that fall into the category of crude diesel, biocrude or aromatic gasoline are produced in a price range of 35 to 85 cents per liter, depending on the technology used. The price of lignocellulosic ethanol is surprisingly high considering the current state of development of TVA's dilute and concentrated acid processes, between $1.15 and $1.90 per liter.
An initial estimate of the cost of producing furans from biomass in the newly developed CSIRO process shows a furan price of between 40 cents and 60 cents per liter in a very narrow price range.
BIOMASS STUDY
ENVIRONMENTAL REVIEW .1 Introduction
- Environmental Criteria
- Lignocellulose Residues to Electricity
- Lignocellulose to Ethanol
- Oilseeds to Oilseed Esters
- Biomass to Oxygenates
The significant environmental benefits outlined for the lignocellulosic to electricity option generally apply to this option, with the main benefit being a significant reduction in greenhouse gas emissions. A detailed assessment of the environmental impacts of this option is not possible as there are no operational conversion facilities. This option provides environmental benefits by potentially reducing the use of fossil fuels for transportation, thereby reducing greenhouse gas emissions from vehicles.
This option offers similar environmental benefits and costs to those outlined for the options from lignocellulosic to ethanol and methanol.
SELECTION CRITERIA AND METHODOLOGY .1 Introduction
- Development and Commercialisation Issues
- Summary
A wide range of biomass systems options have been considered in the study up to this point. In the case of the sawmill waste plant in Orbost, electricity costs are estimated at 5-8 cents per kWh, depending on the feasibility of combined generation at this site. The financial analysis was carried out on the basis of zero raw material cost, for co-production with electricity return prices in the range of 3-7 cents per kWh.
Lignocellulose (including the cellulose component of MSW) was selected, based on the information in the Resources section of this study, as the lowest cost feedstock.
- International Market Opportunities
Cost, competition from non-renewable energy for their production and environmental considerations played a significant role in the decision not to analyze these systems further. An assessment was made of the potential of the seven selected systems in a number of countries in the Asia-Pacific region. A detailed profile for each of these countries has been developed and is presented in the Appendix dealing with international markets.
The starting points are the current status of each system in the US market and the current federally funded development program for biofuels.
LIGNOCELLULOSE
A large part of the hydroelectric power plants is in the scale of mini-hydroelectric power plants and was installed at a relatively low cost. Coal-fired power generation is characterized by low cost, cheap fuel and low conversion efficiency. Coal-fired generation is likely to become even more competitive as plant efficiencies improve.
BIOGAS (ANIMAL AND HUMAN WASTES)
ETHANOL FROM LIGNOCELLULOSE
BIO-DIESEL FROM OILSEEDS
OCTANE ENHANCERS/OXYGENATES
A possible opportunity if the Indian government is successful in reducing the use of animal waste sources directly as domestic fuel. Indian government policy is to discourage the use of animal waste as heating fuel; (Established program to produce biogas in 140 distilleries in India, but this is not in the system definition). Any development or use of this technology in India will only follow the global technological development that will become cost effective (US, Europe).
There is no potential in India for any system that would utilize land, crops or produce suitable for food production.
BIOGAS (ANIMAL AND HUMAN WASTES) Insufficient data available. Prospects would be long term if any
Possible opportunities at agricultural processing plants, especially sugar and rice mills, and from forestry residues. Residue is available from forestry operations and from sugar mills, rice mills, palm oil plants and coconut processing plants. Urban waste management practices and the composition of MSW at Indonesian cities have not been studied from an energy perspective, but will certainly be different from those in Australia and may be unsuitable for energy production.
Any development or application of this technology in Indonesia will follow worldwide technology developments by becoming cost effective (USA, Europe).
METHANOL FROM UGNOCELLULOSE As for System 4
The total potential of agricultural and forest residues is 3700 PJ per year; Current consumption is: firewood 72 PJ; rice residues 30 PJ; other agricultural residual flows 15 PJ; all for thermal use in the rural domestic sector. No reported current use or costs for this system or its resource (however, there are reported to be 361 industrial waste incineration units producing energy for some purpose).
BIOGAS (ANIMAL AND HUMAN WASTES) Potential unknown. Feasibility study required
Feasibility studies are required to evaluate economic viability, but the high cost of electricity production in Korea is favorable. Korea would be a significant potential export market should this system become cost-effective due to the substantial R&D programs in North America and Europe.
OCTANE ENHANCERS/OXYGENATES As for System 4
Production costs: Current production costs are high, but should come down significantly as a result of dramatic increases in generating capacity based on lower-cost resources. Great opportunities with forest waste and in sawmills and plywood factories; especially to upgrade existing low pressure boilers in cogeneration facilities. Also opportunities to expand the already significant cogeneration capacity in palm oil mills, and significant opportunities in rice mills; Considerable source of rubber wood suitable for gasification.
Cogeneration is the norm in the palm oil industry, which is self-sufficient in energy (640 Gwh per year).
BIOGAS (ANIMAL AND HUMAN WASTES) Possible minor opportunity
METHANOL FROM LIGNOCELLULOSE As for System 4
OCTANE ENHANCERS/OXYGENA TES
Resource potential: 15600 PJ per year; logging residues 800 PJ per year, urban wood waste and land clearing 1200 PJ per year; forest production residues 2100 PJ per year; environmentally-collectible agricultural residues 2000 PJ per year; commercial forest wood 4500 PJ per year; improved forest management 4500 PJ per year; shift 2 5 % of the timber industry to energy 500 PJ per year. Current utilization: 25 PJ per year power generation from utilities from wood; 1650 PJ per year industrial heat and power from wood (mainly paper and related products); 20-40 PJ per year commercial heat and power from wood. Existing Capability: For Mass-Burn Type, there are more than 80 installations, either operational or under construction; typically 5-10 MW, and there are numerous US suppliers of the technology.
14 communal boilers have been retrofitted for co-firing RDF with coal or oil, and there are also equipment suppliers from the USA.
METHANOL FROM UGNOCELLULOSE Too early to know whether R&D cost targets will be achieved
Targeted R&D costs: woody plants for energy $3 per GJ; herbaceous energy crops (lignocellulosics) $3 per GJ. competitive with the projected unsubsidized wholesale price of gasoline). Existing Capacities: Research and development is underway to optimize acid pretreatment, xylose conversion systems, cellulase production and economically viable co-products. Existing Capabilities: R&D is underway to engineer gasification auxiliaries and new catalytic synthesis systems.
In addition, research and development is planned and funding is allocated for the commercial development of catalysts and for hot gas conditioning for both catalysis and the BCL gasifier.
OXYGENATES/OCTANE ENHANCERS
In the United States, this system is not considered to have the potential to become cost competitive. Instead, the program has allocated significant funds to the development of biodiesel from aquatic species.). If cogeneration cannot be attracted, the break-even price will fall to $8.7/ton, even for peak electricity prices.
4 Southern California Edison reports that almost all solid waste incineration projects have had major "deposit" facility problems caused by alkali levels in the biomass.
SITE SPECIFIC CASE STUDIES
SITE SPECIFIC CASE STUDIES 6.1 INTRODUCTION
ELECTRICITY FROM DIRECT COMBUSTION AND GASIFICATION Case studies to illustrate the application of heat and/or power generation from biomass
- Cogeneration from Wood Waste .1 Site Energy Demand
- Biomass Resources Available
- Conversion Technologies
- Environment
- Summary and Conclusions
- Cogeneration from Rice Hulls .1. Site Energy Demand
- Biomass Resources Available
- Conversion Technologies
- Economics
- Summary and Conclusions
- Cogeneration from Cotton Wastes
- Site Energy Demand and the Wider Market
- Summary and Conclusions
- Cogeneration from MSW .1. Site Energy Demand
Some of the possible power generation configurations and their characteristics are discussed below. i) The wood waste can be fed into the gasifier to produce combustible gases to fuel a gas engine that drives an alternator. At 14% moisture content, however, the gross caloric value is much lower and is approximately 9.9 MJ per kg. This is the figure used for the economics of the power generation plant. The balance of the steam produces electricity and goes to a condenser for eventual return to the boiler as feed water.
Rice husks are free and by using them in the cogeneration plant, part of the disposal cost is saved.
