The Department of Energy recently released its second “Critical Materials Strategy” report. Credit: DOE.

In late December 2011, the Department of Energy released its 2011 update (pdf) to its report, “Critical Materials Strategy.” This is an update to the inaugural issue report released in 2010.

The 189-page report evaluates the issues relevant to critical materials for wind turbines, photovoltaic thin films, electric vehicles and energy efficient lighting in terms of criticality, market dynamics and technology. The report looks at the rare earth elements that are most used in energy technology and also other elements, such as lithium (see graphic).

Here are the highlights adapted from the executive summary.

Criticality Assessment
Sixteen elements were assessed for criticality in wind turbines, EVs, PV cells and fluorescent lighting. The methodology used was adapted from one developed by the National Academy of Sciences. The criticality assessment was framed in two dimensions: importance to clean energy and supply risk. Five rare earth elements — dysprosium, terbium, europium, neodymium and yttrium — were found to be critical in the short term (present-2015). These five REEs are used in magnets for wind turbines and electric vehicles or phosphors in energy-efficient lighting. Other elements-cerium, indium, lanthanum and tellurium — were found to be near-critical. Between the short term and the medium term (2015-2025), the importance to clean energy and supply risk shift for some materials.

Market Dynamics
In the past year, the prices of many of the elements assessed in this report have been highly volatile, in some cases increasing tenfold. This Strategy includes a chapter exploring market dynamics related to rare earth metals and other materials [including growing demand and slow response from global suppliers, university activities, business reactions to price volatility and material scarcity and roles for government.

Technology Analyses
Building on the 2010 Critical Materials Strategy, this report features three in-depth technology analyses.

Rare earth elements play an important role in petroleum refining, but the sector’s vulnerability to rare earth supply disruptions is limited. Lanthanum is used in fluid catalytic cracking, an important part of petroleum refining. However, lanthanum supplies are less critical than some other rare earths and refineries have some ability to adjust input amounts. Recent lanthanum price increases have likely added less than a penny to the price of gasoline.

Manufacturers of wind power and electric vehicle technologies are pursuing strategies to respond to possible rare-earth shortages. Permanent magnets containing neodymium and dysprosium are used in wind turbine generators and electric vehicle motors. Manufacturers of both technologies are currently making decisions on future system design, trading off the performance benefits of neodymium and dysprosium against vulnerability to potential supply shortages. For example, wind turbine manufacturers are deciding among gear-driven, hybrid and direct-drive systems, with varying levels of rare earth content. Some EV manufacturers are pursuing rare-earth-free induction motors or switched reluctance motors as alternatives to PM motors.

As lighting energy efficiency standards are implemented globally, heavy rare earths used in lighting phosphors may be in short supply. In the US, two sets of lighting energy efficiency standards that come into effect in 2012 will likely increase demand for fluorescent lamps containing phosphors made with europium, terbium and yttrium. The first set of standards applies to general service bulbs. The second set of standards applies to linear fluorescent lamps. The projected increase in US demand for CFLs and efficient LFLs corresponds to a projected increase in global CFL demand, suggesting upward price pressures for rare earth phosphors in the 2012-2014 timeframe, when europium, terbium and yttrium will be in short supply. In the future, light-emitting diodes (which are highly efficient and have much lower rare earth content) are expected to play a growing role in the market, reducing the pressure on rare earth supplies.

The executive summary also outlines DOE’s strategy, which is three-fold: diversify global supply chains (systemic risk management), develop substitute materials and improve recycling/reuse. The strategy was developed through a series of DOE workshops held between Nov. 2010 and Oct. 2011.

The six appendices provide much of the specifics, such as detailed evaluations for each element, market share data for each energy technology, congressional legislation, joint governmental international conference information, DOE funding activities and REE use in refineries.

The report appears to be well organized and comprehensive. The addition of subheadings to the table of contents would have been helpful for navigating quickly through the document.

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