Light-emitting diodes, commonly called LEDs, are a technology that uses semiconductors and electroluminescence to create light. LED lighting can be more efficient, durable, versatile and longer lasting than traditional incandescent light bulbs or compact fluorescent lamps (CFL). As a result, LEDs have become the standard lighting technology for mobile phones, flat-screen televisions, tablets and computer monitors, and growth in global demand for LEDs has largely been driven by the expanding market for these consumer goods. The other main application of LED technology is in street and space lighting - but the timing and penetration of LED lighting versus phosphor (fluorescent) lighting will play a key role here. Forecasts show LED penetration reaching 30% of the total European lighting market by 2015, 46% by 2016, and 72% for 2020 (JRC 2013 / McKinsey, 2012).
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This growth in demand for LEDs has gone hand-in-hand with growth in demand for the critical raw materials used in their manufacture. White light LEDs contain a range of different metals, such as nickel, gallium, arsenic, indium, antimony, cerium, europium and yttrium (JRC 2013). Lutetium and gold are also used in LED production. Gallium arsenide (GaAs) has historically been the most widely used gallium compound semiconductor in LEDs, largely thanks to the fact that it is a faster and more efficient substrate material than silicon and is able to operate over a wider range of temperatures. However, the use of gallium nitride (GaN) semiconductors is expanding. GaN power semiconductors can operate at higher temperatures, power levels, voltages and frequencies than gallium arsenide and silicon and GaN semiconductors are used in LEDs for backlighting of liquid crystal display (LCD) flat panel displays in computers, TVs and mobile telephones, and in signage.1
In 2013 the Joint Research Centre - the European Commission’s in-house science service - conducted a study on Critical Metals in the Path towards the Decarbonisation of the EU Energy Sector, which aimed to identify the metals for which bottlenecks could form in the supply chain of various low-carbon energy technologies. The list of eight metals that were given a high criticality rating and therefore classified as ‘critical’ in the report includes two of the LED components mentioned above - gallium and, to a lesser extent, yttrium. Demand for critical raw materials is predicted to grow generally but, largely thanks to their use in two emerging energy-related applications - LED lighting and solar photovoltaic - the average growth in demand to 2020 for gallium and for heavy rare earths such as yttrium is forecast to be particularly strong, at greater than 8% per year for the rest of the decade.2 Growth in the other main market for gallium – semiconductors - is relatively more modest at around 6% per year (Indium Corporation, 2011). These forecasts clearly indicate that the demand growth for gallium will be very high and that, consequently, there is a risk of market deficits for these materials.3
According to a report from Roskill Information Services, Chinese capacity for primary gallium production has increased and accounted for 80% of the global total in 2013.1 As a by-product of aluminium refining, gallium is highly dependent on one of the most energy intensive metal refining industries. Consequently, it is a resource that the Chinese government has put limitations on in the past.4 Despite an increase in global production capacity, the U.S Geological Survey estimates world production of primary gallium at 280 metric tons in 2013, down 27% from 383 tons in 2012. 5 China, Germany, Kazakhstan, and Ukraine were the leading producers; countries with lesser output were Hungary, Japan, the Republic of Korea, and Russia. Refined gallium production in 2013 was estimated at 200 tons, about 30% less than primary production. China, Japan, the United Kingdom and the United States were the principal producers of refined gallium. Recycling, particularly in Japan, is also an important element of supply.
Scenarios for the installation of lighting and LED penetration in Europe*
*(millions per year)
Source: JRC 2013
In light of China’s monopoly of the market for primary gallium - Europe is faced with a number of options. Although Europe already has a degree of self-sufficiency for gallium and tellurium, a number of opportunities may exist to further boost supply of these materials. One strategy is to adapt technologies and production processes with a view to reducing the amount of critical materials required. Another is to find substitute materials that perform as well or nearly as well at a comparable cost. In this regard, quantum dots are a promising technology for lighting applications. The first commercial lighting applications of quantum dots used them as a coating on blue LEDs to help create a warmer white light - these are known as quantum dot LEDs (QD-LED). Organic light emitting diodes (OLEDs) also have the potential to become a viable rare earth-free alternative to other low-energy lighting technologies such as LEDs and fluorescents. A third option to shore up the European market is to find new or enhanced recycling technologies to increase available supplies.6
One project that aims to do just this is CycLED,7 which is being financed under the European Commission’s Seventh Framework Programme (FP7), and will run from January 2012 to June 2015. CycLED is focused on optimising the resource flows for LED products, including the recycling of scarce key metals in LED production. The project also aims to find ways to optimise the reliability and extend the lifetime of LED products. Another project goal is to identify opportunities for reduced resource losses during production, use and recycling. The expected results of the CycLED project include reducing the environmental impacts and costs of LED production and increasing resource efficiency. The project will also promote closed-loop resource management and separate collection of waste LEDs and LED products.
In its 2013 report, the Joint Research Centre outlines six key areas to address the various concerns regarding the supply risks for critical raw materials, including those used in LED production. These include data collection and dissemination to eliminate information gaps regarding the production, trade, use and even pricing of critical materials. Other important areas are investment in primary production and design and innovation (substitution) and the implementation of resource efficiency strategies. Finally, international cooperation to exchange knowledge, and procurement and stockpiling policies aimed at securing the materials supply chain will also play an important role.8 While highlighting the importance of action to secure Europe’s supplies of critical resources the JRC nevertheless introduces a note of optimism by stressing that the risks of raw materials bottlenecks for key decarbonisation technologies should not be overstated, as numerous risk mitigation options exist.