4.      Aluminum

The aluminum sector makes aluminum out of raw materials (like bauxite, primary aluminum) or out of recycled aluminum (secondary aluminum). Most of the recycling takes place in the industry itself (IPCC 2014a). In primary aluminum making, an electrolysis reaction is necessary, requiring a large amount of electricity (IPCC 2014a). 

4.1.  Activity level

In 2010, aluminum production amounted to 87 Mt (neglecting industry internal recycling to avoid double counting). In 2050, this is expected to increase to 234 Mt (IEA 2014), an increase of almost 169 percent. The demand for aluminum is expected to grow significantly because of its increased application in transport, construction and engineering, in particular in developing countries because of expected economic growth.

4.2.  Emission reduction potential

In 2010, the scope 1 CO2 emissions from the aluminum sector were 141 Mt. By 2050, emissions are expected to increase to 333 Mt (IEA 2014), up to 136 percent, because of the large increase in production.

 

Even though the emissions from aluminum are only a small share of global emissions, the expected increase in activity and the current energy intensity allow for a high reduction potential, with Asia holding more than half of the global reduction potential (IEA 2012a). The quality of the ore used is an important factor in the emission intensity, but there is also potential for technical abatement measures (IEA 2012a). The implementation of best available technologies can reduce energy use for aluminum production by about 10 percent (IPCC 2014a). Recycling more aluminum can also reduce emissions significantly.

4.3.  Carbon intensity pathway

Figure I.4 shows the sector’s intensity pathway. The activity index steadily increases up to more than 2.5 from 2010 to 2050. Emissions are allowed to increase, but at a declining pace. The result is that the carbon intensity needs to be reduced by 88 percent from the 2010 intensity.

 

For indirect emissions (scope 2), decarbonization of electricity can reduce the carbon intensity even further (IEA 2012a). With the increasing decarbonization of the power sector, scope 2 emissions are expected to drop significantly from 2011 to 2050 (from 4.47 tons of CO2 to 0.16 tons of CO2 per ton of aluminum).

 

Figure I.4  Aluminum manufacturing activity steadily increases to more than 2.5 times the 2010 activity by 2050, but carbon intensity needs to decline by 88 percent

Source: based on IEA (2014).