Minor Metals
Renewable Energy Technologies

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Key Facts

Inexhaustible and readily available energy can be harvested by Renewable
Energy Technologies from sources such as the sun, ocean and wind without theenvironmental degradation and depletion of finite resources resulting fromtraditional methods of energy production.

Renewable Energy Technologies provide promising solutions for mitigating therelease of man-made GHGs such as carbon dioxide (CO2) and methane (CH4) into
the atmosphere.

The reliable availability of renewable energy sources helps planning and reducesrisks through more predictable energy prices.

Life Cycle Assessments (LCA) and similar methodologies, when applied toproduct development, aid in recovering minor metals in Renewable EnergyTechnologies.

The deployment of Renewable Energy Technologies on a mass scale across theglobe will create new jobs through the development of new supply chains andinfrastructure.

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The Renewable Energy Outlook
According to the OECD / IEA ‘Medium Term Renewable Energy Market
Report 2013’ the share of renewables in total energy production willincrease across all regions towards 2018. Total renewable generation
equals the sum of bioenergy, hydropower (including pumped storage),onshore and offshore wind, solar PV, concentrating solar power (CSP),
geothermal, and ocean technologies.

Summary
Climate change from man-made emissions is a threat to our current way oflife. Sustainable and secure sources of energy will be key for offsetting
emissions and reducing the potential consequences.

On average, Earth’s surface
continuously receives more than
1000 W/m2 of solar energy.
Photovoltaic(PV)materials
convert solar energy to electricity,with the conversion efficiency(CE) of a material measuring
efficiency of conversion.

Renewable energy technologies have grown massively in the last decade,with technology breakthroughs, support from policy makers anddevelopment of infrastructure.
Photovoltaic (PV) panel manufacturing has been transformed into a mass
production industry in the last five years, in thin-film technologies, as wellas in Si-based technologies (thick-film), which currently dominate thesector. Wind energy turbine installations have also grown massively innumber in recent years, with an increasing use of Rare Earth Element (REE)permanent magnets for efficiency.
Minor metals* are important raw materials in the production ofphotovoltaic systems, wind turbine magnetic motors and structures, andwill remain so, even with technological advances, due to their unique
technical properties. Many minor metals are described by governments andpolicy makers as ‘strategic’ or ‘critical’ due their exceptional characteristics,
certain supply constraints and importance for ensuring a sustainable future.

Did you know that one hour of
direct sunlight is equivalent toour global annual energy
consumption ?
Source : University of Toronto

Wind power density ranges fromClass 1 (the lowest) to Class 7 (thehighest). Good wind resources(with an average annual windspeed of at least 20 kilometres
per hour) are found in manylocations. Wind speed is a criticalfeature of wind resources,
because the energy in wind is
proportional to the cube of thewind speed. In other words, thestronger the wind, the greater thepower.

*The term 'minor metals' encompasses a vast array of metals, including tungsten,titanium, cobalt and molybdenum, to name just a few. Traditionally, minor metals
were those metals not traded on formal exchanges, although cobalt andmolybdenum are now traded on the London Metal Exchange, along with basemetals. Minor metals usually have a relatively low annual production volume,
compared to base metals, and very specialist, and often high technology,
applications.

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The Challenge
To create secure, renewable sources of energy, thereby decreasing
dependence on fossil fuels and reducing CO2 emissions
Carbon dioxide (CO2) is the largest contributor to Earth’s Green House Gas(GHG) inventory, with levels rising dramatically since the start of theIndustrial Revolution. These emissions have increased averagetemperatures, putting the planet at risk from adverse weather events,
rising sea levels and less secure food supplies, amongst other serious anddestructive effects.
Fossil fuel combustion produces the majority of man-made CO2, withapproximately 25% of all GHGs coming from electrical power generation.
Concerns about CO2 in particular are therefore driving demand for
low-carbon and carbon-free sources of energy. Government
decarbonisation strategies around the globe reflect the urgency andimportance of this issue to society. Development of supply chains andinfrastructure, and their associated job creation, is also a key priority forgovernment policy.
Renewable energy resources help to create a secure supply of energy forcountries that do not have their own reserves of fossil fuels. Renewable
resources mitigate risks of supply disruption from natural disasters or
political instability, as well as insulating against price fluctuation.
Global perceptions of renewable energy have shifted considerably over thelast decade. Continuing technology advances and rapid deployment of anarray of renewable energy technologies have demonstrated that theirpotential can be achieved.
Renewable energy provided an estimated 19% of global final energy
consumption in 2012. Of this total share, modern renewables accounted forapproximately 10% , with the remainder coming from traditional biomass*(Renewables 2014 Global Status Report) However, although promising,these figures need to increase significantly if they are to tackle and mitigate
climate change, as well as to cope with a rapidly growing global population.

The Solution
Increase the share of renewable energy resources: with solar, wind,geothermal, (modern) biomass and hydropower all classed as renewableenergy sources.
Energy demand from non-fossil sources has grown steadily since the late
20th Century and is estimated to more than double in the period to 2050,
with the contribution met by solar energy increasing more rapidly.

*Solid biomass, including fuel wood, charcoal, agricultural and forest residues, and animal dung, that is usually produced unsustainably and typicallyused in rural areas of developing countries

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Where minor metals help
Photovoltaics (PV)
Minor metals used in photovoltaics – silicon, indium,gallium, cadmium, tellurium, selenium
Photovoltaic cells (PV) are made up of two semi-conducting layers. Onelayer containing a positive charge and the other a negative. Photons fromsunlight excite electrons into a higher state of energy allowing them to act
as charge carriers for an electric current.

Figure 1 Source: National
Renewable Energy Laboratory

The main commercial PV materials today are:
Crystalline silicon (c-Si)

Amorphous silicon (a-Si)

Cadmium telluride (CdTe)

CIGS (or CIS), an alloy of copper (Cu), indium (In), gallium (Ga) andeither selenium (Se) or sulphur (S)Technologies based on crystalline silicon use relatively thick and rigid
wafers in solar panels, whilst others are thin-film technologies.

Silicon-based cells
Crystalline silicon-based cells dominate PV technology, accounting fornearly 90% of the total global PV market in 2011 (NREL 2011). The main
reasons for this are the relatively low price of silicon-based solar cells and amore complex manufacturing process for CIGS solar cells which has to date
impeded mass production. Figure 1 shows the typical layers found in asilicon solar cell.

Share of Market

PV technologies generate jobs throughout
the value chain in manufacturing, installation,
operation and maintenance of equipment
PV can be easily installed in remote sites,
bringing electricity to underdeveloped
regions, vastly improving quality of life
Small scale PV on domestic roofs localises
energy supply and reduces the need fortransport / pipelines, as associated with fossil
fuels

Indium: PVs make up 8% of the main end uses
(2012) (Indium Corporation)
Gallium: In 2010, PVs (CIGs) accounted for 8% of theoverall demand for gallium

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5Where Minor Metals help
Thin-films
The alternative, thin-film technologies, including CIGS are slightly lessefficient than silicon-based cells, but they have the advantage of being
lightweight, flexible and durable and can be integrated directly into building
materials. Thin-films require less functional material, are manufactured oncontinuous rolls and can be deposited on to flexible substrates. Apart fromCIGS, thin-film technology uses cadmium telluride (CdTe). As of 2011, CdTe
accounted for roughly 10% of the total solar PV market, while CIGS market
share was still closer to 1% of the market. Figure 2 shows the structure of a
CIGS solar cell.

Figure 2 shows a CIGS solar cell

Solar Panels on domestic roofs
For several years, PV panels, mostly thick-film technology, have been appearing on domestic roofs
Benefits of solar panels according to The Energy Saving Trust are:
Cheaper bills



Income earned for the electricity generated

Excess electricity sold back to the grid

Reduced carbon footprint

As of January 2014, 500,000 houses in the UK had solar panels (Department of Energy and Climate Change)
In July 2013, Germany set a world record for electricity produced from solar photovoltaic systems. They had
between 1.3-1.4 million systems producing 23.9 GW of power.
One solar system is installed every 4 minutes in the USA according to Green Tech Media Researchwww.mmta.co.uk
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Where Minor Metals help
Wind turbines – Magnets and Construction
Minor metals used for wind energy - chromium, manganese, molybdenum and rare earths: neodymiumand dysprosiumWind turbines are normally grouped together into wind farms, either
onshore (which includes along the coast) or offshore. Generally windturbines produce more energy offshore due to the more constant andstronger wind. Nevertheless, land-based turbines still account for 98% of all
installed capacity. Industry and academia agree that the in the future there
will be a focus on larger turbines situated offshore.
The basic principle behind wind turbines is that kinetic energy in the formof wind moves the blades, driving a generator. REEs neodymium anddysprosium are used in the generator in permanent magnets. Permanentmagnets reduce the size and weight of the generator. Slow-speed turbines
generate more electricity at slower wind speeds, but these require larger
permanent magnets, which consequently require more REEs.
Wind turbine technology is divided between permanent magnet andelectromagnet generators and between geared and gearlesstransmission. Studies have estimated that 20% of global wind turbine
installations between 2015 and 2020 are likely to use permanent magnets,
rising to 25% for the years 2021-2030.

The use of REEs inpermanent magnets is thehighest value market
sector, and is forecast toincrease. The use of
Nd-bearing magnets inlarge wind turbines is alarge contributor to thistrend. Source: Critical Metals
Handbook

The other minor metals mentioned: chromium, manganese andmolybdenum are to be found in the steel used to build the turbines, inorder for them to withstand sometimes extremely hostile and corrosive
environments, particularly in offshore installations where salt spray andhigh winds test the wind turbines to the maximum.

Facts from the World Wind Energy Association

Wind power meets close to 4% to the global electricity demand
In total, 103 countries are today using wind power on a commercial basis.
WWEA predicts a wind capacity of more than 700,000 MW as possible by 2020.

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Looking Forward
Minor Metals in the Renewable Energy Technology
supply chain
New technologies capable of meeting society’s environmental
requirements have begun to challenge the current power generation
practices across multiple industries. Managing and monitoring the life
cycles of new products and their materials will present new challenges, aswell as opportunities.

Life Cycle Assessments
Life Cycle Assessments (LCAs) provide an opportunity to reduce theenvironmental impact of a product’s supply chain, as well as its life cycle.
This methodology measures the material and energy inputs, and theenvironmental releases of a product throughout its entire life cycle. Someof the largest companies in the world are currently developing LCA
evaluation tools with their software partners. The LCA methodology willcontinue to develop as new techniques are created, and more data iscaptured for evaluation.

Cradle-to-Cradle & Reclamation
A fairly recent approach to product development, cradle-to-cradle, focuses
on a product’s entire life cycle. It sets out understand and better plan notjust for the creation but also for the disposal of products. This is significant
because the greater the integration of the entire supply chain, the morechance there is of creating a product with reduced environmental impacts,and decreased costs. For example, if the product design phase considers
the end-of-life-cycle disposal process, there is a greater chance ofrecovering recyclable materials. Given that many of the materials used inrenewable energy technologies can be difficult to obtain or expensive,product life cycle planning presents an opportunity to recycle and recoverthese materials. Therefore, new models for product development,
distribution and end-of-life-cycle product recovery will be essential for
reducing environmental degradation caused by mining, energy use andwaste disposal.
Although the use of Renewable Energy Technologies shows promise for
reducing the transmission of man-made greenhouse gasses into theatmosphere, it is equally important to consider the supply chains andlifecycles of these technologies. Without an improvement in these systems,society will experience more difficulty achieving its social andenvironmental goals.

8The use of Gallium may
increase in the future dueto the increased interest inconcentrator photovoltaics(CPV). In this technology,
sunlight is concentrated on
to solar cells. Developments
such as improved
conversion efficiency will
help this technology tobecome a significant part of
the PV market by 2016.
Source: Critical Metals Handbook

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The Minor Metals Trade Association (MMTA) has made every effort to ensure that the information presented is technicallycorrect. However, MMTA does not represent or warrant the accuracy of the information contained in this case study or its
suitability for any general or specific use. The reader is advised that the material contained herein is for information purposes
only; it should not be used or relied upon for any specific or general application without first obtaining competent advice.
MMTA, its members, staff and consultants specifically disclaim any and all responsibility of any kind for loss, damage, or injury
resulting from the use of the information contained in this publication.

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