## 3 GHG Emissions and Production Costs of Cellulosic Ethanol
Emissions from land-use change estimated by the GLOBIOM model [31] for miscanthus and switchgrass Fisher-Tropsch biodiesel (a value in the same order of magnitude can be assumed for ethanol) produced in the EU are negative (\(-12\) gCO\({}_{2}\)eq/MJ), indicating that land use change from these crops actually reduces GHG emissions compared to a baseline case without them, mainly due to the increase in soil carbon stock where they are grown [29; 31]. Most other modeling studies, reviewed in [36], found that energy crops are not likely to displace food and fiber crops on agricultural land, but would mostly be grown on abandoned agricultural land, cropland-pasture, and other unused land with low-carbon stocks, resulting in low or negative ILUC emissions. However, there is some uncertainty in the magnitude of energy crop ILUC emissions and additional considerations on the environmental risks of energy cropping as well as options for risk mitigation can be found in [35]. A lifecycle analysis looking at indirect effects, i.e., including emissions which would arise when replacing a material that has been diverted from its original use into fuel production was performed by [29] for a number of pathways, and included wheat straw to ethanol. For this pathway, the current usage of straw in heat and power generation and livestock bedding and feed, mushroom cultivation, and horticulture was considered (more detail of the analysis can be found in [29]). The authors estimated a value of 8 g CO\({}_{2}\)eq/MJ (central estimate) of indirect emission for wheat straw ethanol. Direct and indirect emissions for the two considered pathways are summarized in the following table (Table 2). Several sources mention costs as the main issue for the development of the cellulosic ethanol sector [12; 13; 14]. Results from recent studies investigating production costs of advanced biofuels, including cellulosic ethanol, are summarized below. These studies are: the Joint Research Centre (JRC), Eucar and Concawe (JEC) cost analysis (in publication) [37], the 2017 European Commission report by the Sub Group on Advanced Biofuels (SGAB) [38], and the 2016 report from the International Renewable Energy Agency (IRENA) [15]. For cellulosic ethanol from agricultural residues or woody biomass, cost ranges reported by the three studies (for different years) are summarized in Figure 2.  
The cost ranges depend on the assumptions on the various components of the cost calculations and, in particular, on the cost of feedstock, the scale of the plants, and capital cost. Being at an earlier stage of commercialization, cellulosic ethanol is still facing significant technology challenges and is showing significant capital and operational costs due to the complexity of the conversion processes and low maturity of the technology, but there is potential for future cost reduction [37]. The cost of feedstock is the major contributing factor depending on its accessibility, transportation costs, and also the alternative use. Feedstocks that are used in cellulosic ethanol plants have usually regional prices and they are traded locally. Their price depends on the local amount of production as well as their competing uses [39].