Abstract

According to the Intergovernmental Panel on Climate Change (IPCC), global greenhouse gas (GHG) emissions must be reduced by 50 to 80 percent by 2050 to avoid dramatic consequences of global warming. Scenarios from the International Energy Agency (IEA) indicate that the potential for reduced CO₂ emissions through enhanced energy efficiency and increased renewable energy production is limited. According to the IPCC, a delay in CO₂ emission reductions can lead to dramatic consequences, and a new strategy for reducing CO₂ emissions as soon as possible is required. CO₂ Capture and Storage (CCS) is a technology with potential for large reductions in CO₂-emissions within 10 to 20 years. Therefore, the strategy for reducing global CO₂-emission must be a combination of (1) increased energy efficiency, (2) more renewable energy production, and (3) a wide implementation of CCS. By establishing stronger incentives favouring energy efficiency and renewable energy and by ensuring wide deployment of CCS, global CO₂ emissions can be reduced by approximately 70 percent by 2050 compared to emissions today.

1. Introduction

Emissions of greenhouse gasses (GHG) will increase the average global temperature by 1.1 to 6.4 oC by the end of the 21^st century [1], according to the Intergovernmental Panel on Climate Change (IPCC). A global warming of more than 2 ^oC increase in global average temperature will lead to serious consequences, and IPCC have therefore stated that global GHG emissions should be reduced by 50 to 80 percent by 2050[2].

The consequences of too high global warming will be melting of glaciers, leading to reduced water and food resources. The sea level will rise, and there will be more extreme weather, more draughts, and more floods. As a consequence more than 200 million humans can become climate refugees. Ecosystems will be disrupted, and 15 to 40 percent of all species can be extinct[3,4,5].

CO₂ is the most important greenhouse gas, and anthropogenic CO₂ emissions are mainly a consequence of fossil fuels being the most important global energy sources. Enhanced energy efficiency and increased renewable energy production will reduce CO₂ emissions, but according to the International Energy Agency (IEA)[6], energy efficiency and renewable energy do not have the potential to reduce global CO2 emissions as much as IPCC’s target, i.e. 50 to 80 percent by 2050.

The objective of this paper is to discuss different options for reducing global CO₂ emissions. Furthermore, a strategy for achieving 50 to 80 percent reductions in global CO₂ emissions by 2050 will be suggested. The paper starts by presenting scenarios for global energy and CO2 emissions in Section 2. Different options for reducing global CO₂ emissions are discussed in Section 3, and a strategy for reducing global CO₂ emissions by 50 to 80 percent by 2050 is suggested in Section 4. Conclusions are given in Section 5.

2. Scenarios for Global Energy Demand and CO₂ Emissions

2.1. Global Energy Demand

Analyzing the future energy demand is a prerequisite for predicting future CO₂ emissions. IEA has established two scenarios for future energy demand, a Reference Scenario (RS) which is a business-as-usual scenario, and an Alternative Policy Scenario (APS). In the APS it is assumed that new policies favoring existing environmentally friendly technologies are implemented. Therefore, APS assumes more renewable energy production and a larger potential for energy efficiency than RS.

Future global energy demand is presented in Figure 1. This figure shows that a large increase in global energy demand is expected and that according to the RS, the global energy demand will increase by 50 percent by 2030.