Energy Policy Scenarios to 2050
10.1.6. Climate Change
If policies are to be effective at dealing with climate change, they have to be aimed at the right targets -those parts of the energy sector significant in their emissions and their opportunities for cost-effective reductions. Sustainability will not be achieved if lower emissions are reached at the cost of social and economic development, especially for the two billion people who lack access to modern energy and its attendant services. The analysis shows how different the emissions trends are in different regions of the world and how different are the underlying drivers. It is clear that each country will have to develop its own response to climate change - no simple single solution or even set of solutions will solve all problems for every country.
There are some overall patterns - greenhouse gas emissions tend to rise as the population grows and gets wealthier. If this were the whole story, reducing emissions would indeed be incompatible with sustainable development - the only way of reducing emissions is to slow population or economic growth.
Fortunately, it is not the whole picture. The emission intensity of economies varies significantly (Table B-2). While big, populous economies like the United States and China naturally have the highest level of overall emissions, there are many examples of economies at similar levels of development but with very different levels of emission intensity. France and Sweden, for instance, have relatively low levels of emissions intensity compared with broadly similar countries like Germany and Australia; similarly, Brazil's emissions are lower than South Africa's. There are different reasons for this such as climate differences (there is less demand for heating in some countries than in others) and differences in industrial activity and efficiency, and differing fuel mixes.
Decades are required, even with the most effective application of policy and technologies, to achieve significant sustainable reductions in CO2 emissions from the world's energy economy, in large part because of the time and cost involved in replacing existing and building new infrastructure and other long-lived assets. Just to keep pace with the world's growing energy demands will require $800 billion per year of investment over the next 25 years, according to the IEA. To make this investment climate-friendly is an even greater challenge, but it is possible to scope out a roadmap to try and meet this challenge in three stages: