Perennial Grasses for Bioenergy and Bioproducts

Production, Uses, Sustainability and Markets for Giant Reed, Miscanthus, Switchgrass, Reed Canary Grass and Bamboo

Efthymia Alexopoulou

• Publisher: Academic Press
• Year: 2018
• ISBN:
  9780128129012
• Topic: Technology & Engineering
• Subtopic: Renewable Power Resources
• Index: Technology & Engineering

Perennial Grasses for Bioenergy and Bioproducts: Production, Uses, Sustainability and Markets for Giant Reed, Miscanthus, Switchgrass, Reed Canary Grass and Bamboo brings together a team of international authors to explore the current utilization, sustainability and future perspectives of perennial grasses in the bioeconomy. The book begins by examining the role of these crops as feedstock for bioenergy, in particular advanced biofuels and bioproducts. It then offers five chapters, each covering one perennial grass type, namely giant reed, miscanthus, switchgrass, reed canary grass and bamboo. The book covers their breeding, cultivation, harvesting, pre-treatment, economics and characterization.

The book goes on to present the thermochemical conversion pathways for different types of feedstock. The last chapter explores issues concerning sustainability of perennial grasses, including their production in marginal lands. This thorough overview is a helpful reference for engineering researchers and professionals in the bioenergy sector, whose understanding of feedstock characterization, sustainability and production is critical in the development of conversion technologies.

Those in the industrial crops sector will benefit from discussion of various issues surrounding crop production, which can guide their feedstock cultivation, harvesting and pre-treatment for specific conversion processes or end use. The book is also a useful resource for instructors and students in Masters and PhD programs in the area of biomass and energy crops. Policy makers and government agents involved in regulating the bioenergy and bioproducts sector will find comprehensive information to guide their decision making.

• Explores the whole value chain of grassy feedstock for advanced biofuels and bioproducts, from cultivation to end use, including biomass characterization (physical properties, chemical composition, etc.) and conversion and sustainability
• Examines the sustainability and economic factors related to perennial grasses and their conversion into biofuels and bioproducts
• Includes a complete list of grasses relevant for energy uses, and tables with their current and expected future uses and markets

1

The Importance of Perennial Grasses as a Feedstock for Bioenergy and Bioproducts

Salvatore L. Cosentino^1,2, Danilo Scordia¹, Giorgio Testa¹, Andrea Monti³, Efthymia Alexopoulou⁴, and Myrsini Christou^{4 1}University of Catania, Catania, Italy ²CNR-IVALSA – Consiglio Nazionale delle Ricerche, Istituto per la valorizzazione del legno e delle specie arboree (CNR-IVALSA), Catania, Italy ³University of Bologna, Bologna, Italy ⁴CRES, Center for Renewable Energy Sources and Saving, Pikermi, Attikis, Greece

Abstract

This chapter describes the increasing importance of perennial grasses as a biomass source for both energy and nonenergy applications in Europe. Special emphasis is given to the current legislation on renewable energy and concerns regarding the use of food crops for first-generation biofuel production that led to food versus fuel debates, land use change scenarios, and other environmental concerns. Perennial grasses as the “ideotype” of bioenergy crops, bioenergy chains involving perennial grasses, environmental sustainability, and future research perspectives to bring these species into cropping systems are also underlined.

Perennial grasses are lignocellulosic, low-cost feedstock, able to grow in variegate environments and to thrive on marginal lands. They have been indicated as the leading candidate feedstock for the modern biobased economy to produce a number of high added-value products (i.e., biopharmaceuticals, nutrient supplements, biopolymers), biomaterials (i.e., buildings, phonic insulating, mulching and biodegradable products for gardening and animal bedding), energy carriers (advanced biofuels, heat and power), and by-products (i.e., soil organic fertilizers, green chemistry products).

However, research is still needed in breeding, agronomy, postharvest logistics, and bioconversion to deliver new elite varieties to expand the European market and allow potential yield and desired biomass quality to be reached, while maximizing resources and conversion efficiencies.

Keywords

Bioeconomy; Bioenergy chains; Bioenergy crop; Biomass; European Union; Ideotype; Land use change; Legislation; Perennial grasses; Renewable energy

1.1. Introduction

In a biobased economy context, steady interest is devoted to seeking the most suited bioenergy crop for a specific environment, with specific traits for end-use destination, high yield, and the ability to grow in degraded lands and to be highly competitive with food/feed crops. Perennial grasses for biomass production, such as miscanthus (Miscanthus spp.), reed canary grass (Phalaris arundinacea L.), switchgrass (Panicum virgatum L.), giant reed (Arundo donax L.), and bamboo (Phyllostachys spp.), among others, feature those characteristics typical of the ideotype of bioenergy crops.

This chapter describes the increasing importance of perennial grasses as a biomass source for both energy and nonenergy applications in Europe. Special emphasis is given to the current legislation on renewable energy and concerns regarding the use of food crops for first-generation biofuel production that led to food versus fuel debates, land use change scenarios, and other environmental concerns. Perennial grasses as the “ideotype” of bioenergy crops, bioenergy chains involving perennial grasses, environmental sustainability in a changing climate context, and future research perspectives to bring these species into cropping systems are also underlined.

Perennial grasses are high resource use efficient and high biomass yielding, and are suitable crops for adverse environmental conditions. Their nonedible nature made up primarily by hemicellulose, cellulose, and lignin makes their raw material a very attractive feedstock to produce advanced biofuels or biobased products, fitting the modern biobased economy criteria. As lignocellulosic feedstock, perennial grasses are expected to play an important role in achieving long-term goals for energy policy in cutting CO₂ emissions and contributing to the maintenance of energy supplies. Furthermore, perennial grasses might be grown on less productive cropland, providing benefits in terms of soil structure and stability (e.g., reduced soil loss, erosion, and runoff), soil quality (e.g., increase in soil fertility, organic matter, and nutrient retention), and biodiversity (e.g., cover for native wildlife), at both global and agricultural community scales.

Perennial grasses have been widely used as fodder crops for centuries, often contributing significantly to energy supply on farms from animal power. There has been increasing interest in the use of perennial grasses as biomass crops in the United States and Europe since the mid-1980s (Lewandowski et al., 2003). From the beginning of the 1990s, several European projects investigated perennial grasses, i.e., Miscanthus productivity networks, Giant reed network, Switchgrass for Energy, Bioenergy Chains, 4FCROPS, and EUROBIOREF, among others (Alexopoulou et al., 2015). The European Commission has funded three research projects under the theme “KBBE.2011.3.1-02, Perennial grasses: optimising biomass production—SICA” with the aim of upscaling both cultivation and bioconversion techniques of perennial grasses, with special focus on marginal lands of south (OPTIMA, 289642), center (OPTIMISC, 289159), and north Europe (GrassMargins, 289461), whose main results can be found at the “Perennial Biomass Crops for a Resource Constrained World” conference proceedings (www.biomass2015.eu).

However, perennial grasses for biomass production are largely undomesticated plants, and are still at the early stages of development and improvement (Zegada-Lizarazu et al., 2010). Most of them are still in their wild form, collected from wild environments and tested in field trials, and hence at the very first stage of breeding programs. Thus proper varieties, their agronomic practices, and other postharvest logistics are still not optimized to reach their potential yield in a given environmental con...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• List of Contributors
• Introduction
• 1. The Importance of Perennial Grasses as a Feedstock for Bioenergy and Bioproducts
• 2. Miscanthus
• 3. Switchgrass: From Production to End Use
• 4. Giant Reed: From Production to End Use
• 5. Reed Canary Grass: From Production to End Use
• 6. Bamboo Production for Industrial Utilization
• 7. Suitability of Perennial Grasses for Energy and Nonenergy Products
• 8. Sustainability of Perennial Crops Production for Bioenergy and Bioproducts
• Index