Renewable energy

although a precise baseline was not specified. The 80 per cent reduction would yield some space for developing countries to have a less stark reduction trajectory while reaching the global 50 per cent target. There are still large uncertainties, however, concerning how to reach the emission reduction goals and the two-degree target agreed by most countries at the UN Climate Change Conference in Copenhagen in 2009. If pledges made subsequent to the conference were implemented together with other policy options under consideration in the negotiations,5

reach 49 GtCO2

emissions in 2020 are projected to -eq, which leaves a gap of at least 5 GtCO2

-eq (UNEP 2010b). In the -

eq relative to the projected level required for the two- degree target of 39-44 GtCO2

IEA Current Policies Scenario, fossil fuels are projected to continue dominating energy supply in 2030 (see Table 2). Additionally, several models project that GHG emissions will rise fastest in high-growth countries such as China and India (IEA 2010b, 2010d).

A shift from fossil fuels to renewable energy in the energy supply can contribute to achieving ambitious emissions-reduction targets, together with significant improvements in energy efficiency. To reduce emissions to a level that would keep the concentration of GHGs at 450 ppm in 2050, the IEA projects that renewable energy would need to account for 27 per cent of the required CO2

reductions, while the remaining part would

result primarily from energy efficiency and alternative mitigation options such as carbon capture and

sequestration (CCS) (IEA 2010b). A major part of the CO2 reductions resulting from the promotion of renewables would take place in developing countries.

2.3 Impacts of energy technologies on health and ecosystems

There are high indirect costs associated with the pollution

arising from combustion of fossil and

traditional fuels. The release of both black carbon particles (from incomplete combustion of fossil fuels) and other forms of air pollution (sulphur and nitrogen oxides, photochemical smog precursors, and heavy metals, for example) have a detrimental effect on public health (UNEP and WMO 2011). Indoor air pollution from burning solid fuel accounted for 2.7 per cent of the global burden of disease in 2000 and is ranked as the largest environmental contributor to health problems after unsafe drinking water and lack of sanitation (WHO

5. These options include countries moving to higher ambition, conditional pledges; and the negotiations adopting rules that avoid a net increase in emissions from (a) “lenient” accounting of land use, land-use change and forestry activities, and (b) the use of surplus emission units (UNEP 2010b). .

6. The IEA calculation includes international costs of pollution control equipment and has been done using a four per cent (social) real discount rate. All costs and prices are expressed in constant € 2005 and include “current policy” pollution control legislation.

Total energy use

[Mtoe]

Coal Oil

Gas

Nuclear Hydro

Biomass and agricultural waste and/or residueb

Other renewables Total

2008 3,315 4,059 2,596 712 276

1,225 89

2035 5,281 5,026 4,039 1,081 439

1,715 468 12,271 18,048

Current Policies scenario Source: IEA (2010d)

2006). Burning fossil fuels costs the United States about US$ 120 billion a year in health costs, mostly because of thousands of premature deaths from air pollution (NRC 2010). This figure reflects primarily health damage from air pollution associated with electricity generation and motor vehicle use. According to the IEA, the costs of air pollution controls worldwide amounted to about € 155 billion in 2005 and are estimated to triple by 2030 (IIASA 2009; IEA 2009a).6

Renewable energy can mitigate or

avoid many of these public health risks caused by the mining, production and combustion of fossil fuels.

The use of fossil and traditional energy sources in both developed and developing countries also impacts global biodiversity and ecosystems through deforestation, decreased water quality and availability, acidification of water bodies, and increased introduction of hazardous substances into the biosphere (UNEP 2010a). These impacts also reduce the natural capabilities of the planet to respond to climate change.

Renewable energy technologies are not without impacts and careful planning to address possible environmental and social impacts are essential. Production of biofuels, for example, can have negative impacts on biodiversity and ecosystems, while the environmental and social impacts of large-scale hydropower can be significant. The World Commission on Dams has provided guidelines for reducing possible negative impacts of hydropower development. First-generation biofuels

have also

received substantial attention for their impacts due to land-use change and agricultural production practices, leading to the development of biofuel sustainability standards (see Section 5.7). Increased mining activity and deforestation could result from increased use of renewable energy sources requiring rare earth elements,

207

Growth rate 2008-2035a [%]

1.7 0.8 1.7 1.6 1.7

1.3

6.3 1.4

Share in total energy mix [ % ]

2008 27.0 33.1 21.2 5.8 2.2

10.0 0.7 100.0

a. Compound average annual growth rate. b. Includes traditional and modern uses. Table 2: World primary energy mix in the IEA

2035 29.3 27.8 22.4 6.0 2.4

9.5 2.6 100.0