As of 2010, total world greenhouse gas (GHG) emissions amounted to about 45,000 million metric tons (mmt). In order to control climate change, the Intergovernmental Panel on Climate Change (IPCC) estimates that total emissions will need to fall by about 40 percent as of 2030, to 27,000 mmt, and by 80 percent by 2050, to about 9,000 mmt.
Of the 45,000 mmt of total GHG emissions, about 82 percent are generated by energy-based sources. This includes 33,615 in CO2 emissions from energy sources, equaling about 75 percent of total GHG emissions itself.
This report focuses on measures to reduce CO2 emissions from energy-based sources. Expressed on a per capita basis, global CO2 emissions in 2010 averaged 4.6 metric tons (mt). We can express our intermediate emissions reduction goals in terms of this measure, within the framework of reducing the absolute level of carbon emissions by 40 percent, to around 20,000 mmt, within 20 years. With global population expected to rise to about 8.4 billion by 2030, this means that carbon emissions will need to be at no more than 2.4 mt per capita within 20 years.
The purpose of this report is to examine policy frameworks through which these CO2 emission reduction targets can be met, without inhibiting the opportunities for economies to grow and expand well-being for their citizens. We are especially concerned that developing countries be able to grow at healthy rates as the global clean energy transition advances. For developing countries to sacrifice economic growth as a means to reverse climate change will also entail sacrificing opportunities to expand decent employment opportunities and dramatically reduce poverty. Limiting opportunities for countries to proceed on a healthy economic growth trajectory will also face formidable political resistance. This resistance will in turn create unacceptable delays in proceeding with effective policies to control climate change.
The core arguments of this report are simple. We argue that the global economy is capable of meeting the IPCCs’ 20-year intermediate emission reduction target if most countries – including especially most countries with either large GDPs or population - devote about 1.5 percent per year of their economy’s GDP to investments in energy efficiency and clean renewable energy sources. These clean renewable sources include solar, wind, geothermal, and small-scale hydropower, as well as low-emissions bioenergy sources. They exclude corn ethanol and other high-emissions bioenergy sources, whose use generates CO2 emissions at levels equivalent to oil. We conclude that, as a general proposition, countries that sustain this 1.5 percent of GDP level of annual investments in energy efficiency and clean renewables will also be able to maintain economic growth at healthy rates while providing a sufficient supply of energy resources to undergird growth. These investments in energy efficiency and renewable energy will also be a net new source of job opportunities. More specifically, new investments in energy efficiency and renewable energy will generate more jobs for a given amount of spending than maintaining or expanding each country’s existing fossil fuel sectors.
