T. R. BROWN, Iowa State University, USA, M. M. WRIGHT and Y. ROMAN-LESHKOV, Massachusetts

Institute of Technology, USA and R. C. BROWN, Iowa State University, USA

DOI: 10.1533/9780857097385.1.34

Abstract: This chapter covers techno-economic assessments (TEA) of advanced biochemical and thermochemical biorefineries. We discuss how governments, companies, and academic institutions are affecting the economic prospects of advanced biorefineries. The text describes their economic challenges and the various strategies being pursued to increase commercial adoption of advanced biorefineries: government incentives, facility scale-up, and technological innovation. Finally, we present an overall view of emerging trends in biorefinery TEAs with the intent of identifying key opportunities for improvement.

Key words: biorefinery techno-economic analysis (TEA), advanced biofuel incentives, biomass costs and logistics, thermochemical and biochemical conversion.

2.1 Introduction

The pace of biorefinery technology research and development is increas­ing, fueled by concerns over energy security and environmental impacts. Academic institutions and national laboratories are leading the assessment of promising biorefinery concepts. These assessments investigate concepts at various development stages — from laboratory research to plant-scale commercialization. In this chapter we summarize recent techno-economic analysis findings, discuss how policy influences biomass trade and industry subsidies, and describe the differences between national and regional biorefineries. Our concluding section contemplates the impacts of current challenges and emerging trends.

The term biorefinery encompasses different types of facilities that can convert biomass into valuable products (Brown, 2003). We define a biorefinery as an integrated facility capable of producing fuel, electricity, chemicals, and other types of bioproducts. This concept allows for the full

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utilization of biomass compounds and the versatility to vary the product distribution. This concept builds upon the desire to replace every product derived from a barrel of crude oil. In addition to the main industrial building blocks, researchers envision biorefineries that could produce novel types of chemicals and polymers.

There are several biorefinery concepts at various stages of development and commercialization. Their future prospects depend on technological innovation and market conditions. Given the multiple steps required to convert biomass into marketable products, research breakthroughs along any of the conversion steps could accelerate the adoption of a given pathway. Similarly, market conditions could turn formerly unprofitable schemes into commercial successes. More than likely it will be a combination of technological and economic changes that lead the way to commercially — viable biorefineries. Thus, techno-economic assessments provide a unique perspective on current and future biorefinery technologies.

The United States and European governments have established guidelines and incentives to develop renewable fuels. Biorefineries that meet specific government conditions are eligible to receive financial incentives in the form of subsidies. Biorefinery subsidies are projected to increase from US$66 billion today to almost US$250 billion by 2035 (Anon., 2011).

Some biorefinery subsidies have expired in recent years without major impacts to industry growth, signaling the maturity of the biofuel market. However, government subsidy programs have begun to set strict requirements relating to direct and indirect lifecycle greenhouse gas emissions (GHG) on advanced biorefineries as a condition of participation. In order to meet these requirements, renewable energy companies are seeking novel approaches to convert a wider range of biomass into cleaner, cheaper bioproducts. This search requires the assessment of the technical and economic prospects of novel pathways. Therefore, governments are collaborating with academic institutions, national laboratories, and commercial enterprises.

The diffuse nature of biomass availability means that biorefinery scale-up will have wide area impacts on local, regional, and national scales. Although most biorefineries today are limited to capacities of about 100 million gallons (379 million liters) per year, process development and improved biomass logistics could lead to larger biorefineries that gather biomass from hundreds of square kilometers via truck, rail, or barge transport. These biorefineries will present novel, international case scenarios. Thus, there is interest in studying the challenges and opportunities for biorefineries in the global market from a TEA perspective.

The biomass industry presents a rapidly changing landscape with challenges and opportunities. Three recent trends have emerged as the result of faltering government support, sustained high petroleum prices, and changing public opinions on biorenewables: the replacement of starch feedstocks with lignocellulosic biomass, interest in thermochemical pathways, and public and private investment in high-risk, high-reward alternatives.

Lignocellulosic biomass has historically proven difficult to convert into bioproducts with traditional biochemical approaches due to the biological recalcitrance of cellulose and antimicrobial properties of lignin. Develop­ments in genetic and metabolic engineering have opened new pathways to convert hemicellulose into valuable products. These avenues range from enhancing biomass growth to developing bacteria strains capable of digesting formerly discarded or toxic parts of biomass crops.

Thermochemical research pathways have attracted recent attention due to their ability to inexpensively convert lignocellulosic feedstocks to energy — dense gases and liquids. Most of the recent development in the field has been on adapting conventional commercial processes (such as those employed by petroleum refineries) to handle biomass feedstocks and biobased intermediate products. However, there are growing efforts in the search for novel catalysts that can optimize the selectivity and yield of desired bioproducts. Finally, researchers have also proposed hybrid approaches that combine the strengths of the biochemical and thermochemical platforms (Brown, 2005).

There is growing commercial and political support for the develop­ment of high-risk, high-reward platforms such as microalgae-to-fuels, furan synthesis, and sugar-based hydrocarbons. Government-funded algae research was eliminated in the 1990s in favor of ethanol but has recently staged a resurgence due to concerns over land availability and GHG emissions.