Case Studies

Unlocking Limitless Renewable Energy

Nuclear fusion—the opposite of nuclear fission, which happens in nuclear power plants—occurs naturally in the sun, and we have it to thank for life on Earth. Hydrogen atoms fuse to form helium, which has a smaller mass than the original atoms, and the difference is released as energy that we experience as sunlight. If scientists can reproduce this process here on Earth, we could have an inexhaustible source of clean fuel. UK-based company Tokamak Energy is seeking to achieve just this, and copper is a key piece of the puzzle.

Mimicking the sun is an enormous scientific and engineering challenge. The temperatures needed for efficient fusion are over 100 million degrees. Thanks to its excellent electrical conductivity, copper—specifically oxygen-free high conductivity copper (OFHC)—can be used make field coils that enable the generation of very strong magnetic fields to contain the reaction, bringing us one step closer to the Holy Grail of limitless renewable energy.

A Greener Way to Travel

When it comes to electric vehicles, copper plays a critical role in their production, energy storage and charging infrastructure. Just as vehicles with internal combustion engines require a network of filling stations, electric vehicles will need a network of charging stations, and these are based on copper technologies.

Energy storage is thought to be the most copper-intensive aspect of electric vehicles, with an estimated 1.1–1.2 kg of copper used for every kilowatt hour of a lithium ion battery. Beyond that, copper is used in the rotors that drive electric motors, busbars, windings and wiring.

Looking farther ahead, copper’s importance in electromobility may increase still more with the emergence of energy-independent vehicles that use copper-powered solar photovoltaic panels to harness the power of the sun.

Making Batteries Safer

Many objects around the home—such as shavers, mixers, TV remotes, cameras and torches—would be useless without the batteries that power them.

Alkaline battery operation is based on the conductivity of copper, with so-called battery nails functioning as anode current collectors, and a new type of battery wire has simplified the mechanics even further, making batteries safer and more environmentally-friendly.

The new battery wire uses a modified copper alloy that already contains a necessary element—tin—thereby eliminating the old electro-plating process and its related waste stream. The new wire increases safety by halving the production of hydrogen gas. It also offers cost savings, limits leakage and extends battery life.

Improving Vehicle Comfort and Safety

Automotive manufacturers are continually striving to make their products more fuel efficient and environmentally friendly, comfortable and attractive, but they need to achieve all this without adding extra weight.

Brass alloys have been used for decades in the automotive and industrial equipment sectors. However, as the operating temperature of combustion engines has continued to increase, new alloys are required to deliver the necessary performance. The copper industry has designed an innovative brass alloy, specifically to meet the high-performance requirements of automotive and machine building applications.

The new alloy offers the potential to realise lightweight construction and space savings, supporting the downsizing trend in automotive engine technology. It has a far better resistance to heat—compared to competing materials—and shows no signs of softening even up to 400°C. It also has outstanding wear resistance, is more environmentally friendly (in both production and end-use) and retains the advantages of other brass alloys, such as superior machinability and workability.

Empowering Affordable Solar Energy

With traditional sources of energy unlikely to last forever, the hunt is on to find the most sustainable alternative means of supply. Photovoltaic technology, powered by the sun, has matured far more rapidly than foreseen and surpassed what was originally expected of it. Solar panels have quickly become more popular and hence more affordable, and copper has played a key role.

Due to its intrinsic characteristics—such as conductivity and useful mechanical properties—copper has always been the material of choice for the efficient extraction of electricity from solar cells. Relatively thick but soft copper is preferred for use in silicon cells to reduce fragility, and because soft copper offers faster throughput and better low yield strength.

With this in mind, manufacturers created a new copper-based material that makes the automated, mass production of solar panels possible. The new PV connector ribbon, as it’s known, consists of an extremely pure type of copper rolled flat from a round wire and then coated with tin. The product’s key benefit is its strength. PV ribbons allow for the production of thinner wafers, reduced electrical resistance, maximised power output and a far more automated production process.

Keeping Trains Fast and Reliable

Now that we’ve experienced the benefits of high-speed trains, taking us to where we want to be faster and more conveniently than even before, we wouldn’t want to go back. Thanks to the copper industry, we won’t even have to think about it. A new generation contact wire provides a superior alternative to the costly copper-silver contact wire commonly used in the overhead catenary systems, and it’s kinder to the environment. The new wire, which is still > 99.9% copper, incorporates very small amounts of alloys that improve wear resistance, by up to 50%, without reducing conductivity. By adjusting the alloy composition, a producer can tailor the wire’s performance to meet specific customer requirements.

One important factor in increasing the top speed of trains is the ability to keep the engine’s pantograph in continuous contact with the overhead power line. As the train’s speed increases, the more the power line moves up and down, a phenomenon known as wave propagation. The higher tension of the new wire reduces this movement enabling maximum speeds to be increased.

In comparison to existing copper-silver based wires, the new wire also offers a 40% cost saving and up to 50% lower wear. The latter results in substantially longer service lives, lowers routine maintenance efforts and improves resource efficiency, since fewer replacements lines are required.

Protecting Offshore Power Plants

As the need for alternative energy supplies increases, offshore structures, such as wind farms become more important. However, as with existing oil and gas platforms, their marine locations expose them to heavy stresses and a severely corrosive environment. They must withstand seawater and UV light, plus tidal and wave action. Protection of these steel structures has always been a challenge for traditional protection methods since part of the metalwork is not continuously in contact with seawater. A new type of boat-landing, developed by the copper industry specifically for wind farms, provides a protective cloak around vulnerable areas and offers reliable protection against humidity and high salinity.

The boat-landing is completely sheathed with a copper-nickel alloy which has proven to be a very cost-effective and long-lasting alternative to conventional coating systems. It is seawater-resistant and already used widely in marine applications due to its excellent resistance to corrosion. Copper-nickel also more easily absorbs impacts from the docking manoeuvres of the maintenance ships. This alloy is easy to work with and has outstanding welding properties both of which shorten installation times and maintenance work.

Increasing the Efficiency of Air Conditioning

Originally designed for public spaces, in warm climates, air conditioning (AC) systems have become increasingly popular in our offices, our modes of transport and even our homes. As a result, the amount of energy used by these systems has also increased. The HVAC industry has responded by looking for solutions that are more energy efficient, use less refrigerants, including those that are not harmful to the ozone layer, and are more economical overall.

Copper innovations in tube design have delivered significant performance benefits to the overall performance of AC units. New the tubes are both smaller in diameter and feature micro grooves on the inside wall. Together, these characteristics improve heat transfer between the refrigerant and the tube walls and improve energy efficiency. The tubes require less material, allow the use of lower refrigerant charges, and offer enhanced design flexibility. While consumer unit redesign may be desired, for aesthetic purposes, the new tube technology remains compatible with existing production methods and equipment used in the HVAC industry. These MicroGroove tubes are available in a range of alloys to ensure they can meet all market needs.

Enabling Smaller Electronic Devices

When Alexander Bell invented the telephone, his aim was to enable two individuals to talk to one another without being in the same location. What would he make of today’s devices? Making and receiving phone calls is a very minor part of what today’s (mobile) phones are used for. Consumers demand large memories, cameras, music players, sensors and many other features, and all in a much smaller package. The need for miniaturisation makes the micro-soldering of gold wire or tin-based flip chip extremely difficult and, as a result, traditional wire bonding interconnections between chips and external circuitry has reached its limits.

The industry has found a way to extend those limits by using copper pillar technology. This eliminates the problem of micro-soldering as the pillars are deposited directly onto the wafer through a so called ‘bumping’ with the tin-silver solder caps that create interconnections between the chip and the substrate. This innovation allows smaller input-output distances, compared to micro-soldering, and increases the quality and reliability of interconnections. For manufacturers, it means cost savings, increased design flexibility, processability and reliability, and less environmental impact. For consumers, it means the enjoyment of increasingly performing products.