Energy is a key resource in the production of both alumina and aluminium due to the energy intense nature of the businesses. In 2016 AWAC continued the transformation of its asset portfolio which commenced in 2014. Concentrating on repositioning its portfolio of assets resulting in the closure or sale of high cost assets and concentrating on low cost production facilities. In 2016 it was announced that all production at the Point Comfort refinery in Texas would be curtailed.This transformation process included the challenge of replacing reliance on more expensive and inefficient fuel sources at existing operations such as the alumina refinery located at San Ciprian in Spain. In 2016, energy represents approximately 23% of the cash cost of production for alumina and 24% for aluminium.
Direct energy (coal, natural gas, fuel oil) is largely used in the alumina refining processes and is often determined by regional access to fuel sources. AWAC’s Australian and US refineries are largely dependent on natural gas – a clean transitional fuel. In February 2015, the San Ciprian alumina refinery completed its transition from reliance on residual fuel oil as its principle energy source to the cheaper, more efficient and more environmentally friendly natural gas. In January 2017, AWAC announced the closure of the Suralco alumina refinery in Suriname (which has been fully curtailed since late 2015). The Suralco refinery was dependant on fuel oil as its major source of energy. The Alumar refinery in Brazil in which AWAC has a 39% interest, is dependent on a mix of coal and fuel oil. Comparatively small amounts of petrol/gasoline and LPG are used, while biodiesel fuels power some mobile equipment and industrial vehicles on site.
In recent years the availability and rising cost of energy has been a driver for a shift in the geographical location of alumina/aluminium facilities. Energy rich regions such as the Middle East witnessed an increase in investment in aluminium production facilities. AWAC has a 25.1 per cent interest with Saudi company Ma’aden in the development of a bauxite mine and a low cost alumina refinery.
In 2016, the Portland aluminium smelter in which AWAC has a 55% interest, sourced its electricity (indirect energy) from coal fired energy providers.
Energy efficiency is a key factor in sustainable business and environmental performance. AWAC has achieved success in technology and process advancements that have resulted in improved energy consumption and reduced GHG emissions.
Energy utilisation and security
Energy security is vital to maintaining a sustainable business. AWAC’s operations are highly dependent on the availability of base load energy. In 2016 energy consumption for all of AWAC's operations globally on a full facility basis was approximately 37 million MWh (2015: 40 million MWh). The reduction in energy usage compared to 2015 is largely attributable to the curtailment of production at the Point Comfort alumina refinery.
In 2014 it was announced that a new 12 year natural gas supply agreement had been entered into for the Western Australian refineries which secured approximately 75% of the maturing energy supply requirements from 2020 to 2030. In Western Australia, AWAC's three alumina refineries - Kwinana, Pinjarra and Wagerup - are currently powered on gas sourced primarily from the North West Shelf and have two gas-fired cogeneration units.
Cogeneration is around 75% energy efficient compared to 30% to 50% for other power plants operating in Western Australia. A year’s electricity from each of Pinjarra Refinery’s cogeneration units saves approximately 450,000 metric tons of greenhouse gas emissions compared to a similar-sized coal-fired plant. That’s roughly equivalent to preventing the annual emissions from around 112,000 average cars. In addition, the cogeneration plants reduce our refinery emissions by 270,000 metric tons per year through more efficient steam generation.
It was announced in 2017 that an agreement was reached to supply electricity to the Portland aluminium smelter for a period of four years.
Results and goals
- In 2016, alumina production decreased by approximately 16.5 per cent compared to 2015 across the AWAC network of refineries largely due to the closure of the Suralco refinery in Suriname and the curtailment of production of the Point Comfort refinery in 2016 partly offset by increased production at Australian refineries and the Spanish refinery. Over the same period, AWAC's total absolute energy usage at its alumina refineries decreased by approximately 14.5 per cent as a result of refinery curtailments and closure of Suralco.
- AWAC's alumina refineries total energy intensity (energy per tonne of production) in 2015 was 2.56MWh per tonne of production, in line with 2015. Direct energy intensity for alumina production remained static year on year.
- Total energy intensity at AWAC's Portland aluminium smelter in 2016 improved marginally by approximately 0.9% compared to the 2015 year.
- In 2010, Alcoa recommitted to driving further improvements by setting 2020 and 2030 goals focussing on decreasing energy intensity and greenhouse gas emissions. Alcoa’s long-term strategic targets for its Global Primary Products business (that includes AWAC’s alumina refineries) are a 10 per cent reduction in energy intensity from a 2005 baseline by 2020 and 15 per cent by 2030.
- In 2016 AWAC had experts investigating whether the use of solar energy to power the calcination process and solar gas reforming (using solar energy to increase a gas streams energy) in the refining process.
AWAC Full Facility Direct Energy consumption by source (Mines, refineries and smelters)
|AWAC DIRECT ENERGY SOURCE||PURCHASED/PRODUCED||2012 GJ||2013 GJ||2014 GJ||2015 GJ||2016 GJ|
|Residual fuel oil||Purchased||43,525,955||42,758,746||38,482,698||17,297,114||9,908,159|
*Coal energy usage is higher due to the application of a higher energy content factor (14.5 actual) compared to an estimate of 10.2 applied in previous years.
** Reliance on coal declined with the closure of the Pt. Henry aluminium smelter located in Victoria in August 2014 and the subsequent closure in 2015 of the Anglesea (coal fired) power station.
AWAC Indirect Energy consumption by source (Mines, refineries and smelters)
|FULL FACILITY 2012GJ||FULL FACILITY 2013GJ||FULL FACILITY 2014GJ||FULL FACILITY 2015GJ||FULL FACILITY 2016GJ|
Non-renewable electricity declined in 2016 partly due to the closure of the Suralco alumina refinery in Suriname and the full curtailment of the Point Comfort refinery in Texas. Renewable electricity declined significantly due to the closure of Suralco refinery that received electricity from the Afobaka hydroworks.