STIJN CORNELISSEN, MICHELE KOPER, and YVONNE Y. DENG

3.1 INTRODUCTION

To reduce human dependence on fossil fuels and to reduce climate change, we need to make a switch to a fully renewable energy system with no or low associated greenhouse gas emissions. In our Ecofys Energy Scenario modelling, we describe the transition to such a system towards 2050 reach­ing 95% renewable energy without a major reduction in activity levels [1]. In the Ecofys Energy Scenario we describe how energy efficiency options and non-bioenergy renewable options can accommodate the majority of this transition. However, after applying these options, there is still a large demand that needs to be met with sustainable bioenergy options. This is illustrated in Fig. 1.

From Fig. 1 it becomes clear that the majority of this remaining de­mand consists of energy carriers that cannot be easily provided by renew­able options other than bioenergy. These include:

• Transport fuels where energy storage density is often a crucial factor; es­pecially:

о Long distance road transport о Aviation о Shipping

• Industrial fuels where electric or solar heating is insufficient; especially: о Long distance road transport

о Applications that require a specific energy carrier, e. g. a gaseous fuel or solid fuel. One example is the steel industry where the structural strength of a solid fuel is required.

In this study we answer the question: can we meet the remaining en­ergy demand in a fully renewable system like the Ecofys Energy Scenario using only sustainable bioenergy options?

In literature, there have been several attempts to quantify the potential of biomass available for energy supply with varying degrees of sustain­ability constraints. Estimates can differ within a very large range, depend­ing on whether the study takes a holistic view at land management and how stringent the applied sustainability criteria are. Not many of these studies look at the end uses for this biomass potential in detail [2], [3], [4], [5], [6], [7], [8], [9], [10] and [11]. Other studies postulate the use of biomass to fill a demand need, but do not always specify in detail where this biomass would come from [12], [13] and [14]. None of these studies is as comprehensive, as stringent in the applied sustainability criteria and as detailed on both the supply potential and the demand side use of biomass as the study we present here.

This is represented by our detailed bioenergy potential modelling ap­proach that acknowledges that:

• Bioenergy requires a thorough analytical framework to analyse sustainabil­ity, as cultivation, harvesting and processing of biomass and use of bioen­ergy have a large range of associated sustainability issues.

• Bioenergy encompasses energy supply for a multitude of energy carrier types, e. g. heat, electricity and transport fuels, using a multitude of differ­ent energy sources. Therefore a detailed framework of conversion routes is needed.

■ Fossil & Nuclear

■ Remaining demand tor bioenergy: Transport fuels

■ Remaining demand for txoenergy: Industry heat A fuels

1 Remaining demand for bioenergy: Building heat

Remaining demand for bioenergy: Electricity

Other renewables

2000 2010 2020 2030 2040 2050

The outline of this approach is described in Section 2. For clarity, Sec­tion 3 presents detail on the steps of the followed methodology alongside the results obtained from the analysis. In Section 4 we discuss the sensitiv­ity of our results and compare them to bioenergy potential values found in literature. In Section 5 we draw conclusions from our work and answer whether sustainable bioenergy options can meet the remaining demand in the Ecofys Energy Scenario.

3.2 APPROACH

From the demand modelling and supply modelling of all non-bioenergy options in the demand scenario, we find a remaining energy demand that needs to be met with bioenergy options. We applied technological choices (Section 2.1) and sustainability criteria (Section 2.2) to establish how this demand could be met.