Global infrastructure requires major transformation to counter growing congestion in cities, problems with pollution, and intensified trade. Transport systems in particular are fundamental to moving goods and people, while facilitating education, healthcare and economic opportunities. These systems can become more inclusive and sustainable thanks to technology – bolstered by products from the mining and minerals sector.
Transport infrastructure is a key driver of economic and social development – connecting people to jobs, education, and health services.
In developing countries, rural roads play a crucial role in improving access to healthcare, connecting farmers to markets, and enabling children to reach school. Yet around one billion people in the more remote areas of developing countries remain without access to an all-weather road network.
Simultaneously, more than 55% of the world’s population live in urban areas, with this figure expected to grow to 68% by 2050. According to predictions, this ongoing process of urbanisationwill be accompanied by an increase in the number of vehicles on the roads, reaching an estimated two billion by 2050. This in turn is associated with growing congestion and air pollution.
As well as providing connectivity at a more local level, transport infrastructure also facilitates global trade – allowing for more integrated systems of production, distribution and consumption. And as demand for goods increases, infrastructure continues to expand.
For example, intra-African freight volumes are projected to increase more than sevenfold by 2050, and intra-Asian freight volumes more than fourfold – with the bulk of this being reliant on road transport. Due to changing global trade patterns, it is estimated that average transport distances around the world will increase by 12% by 2050, while international freight transport volumes will increase more than fourfold during the same timeframe.
The expansion of infrastructure brings many economic benefits, but it also creates sustainability challenges. It is expected that CO2 emissions from freight transport alone will grow by 290% by 2050, with freight becoming the main source of CO2 emissions from surface transport.
Transport as a whole is also responsible for a significant share of resource use and contribution to climate change – with its environmental impact expected to grow dramatically if a business-as-usual approach is continued. Transport accounts for 64% of all global oil consumption, 27% of energy use, and around a quarter of energy-related CO2 emissions. Though cars and trucks are responsible for the majority (around 75%) of transport-related CO2 emissions, aviation and shipping emissions are also growing rapidly. What’s more, each year almost 185,000 deaths around the world can be directly attributed to pollution from vehicles.
In order to meet the aims of SDG9, there’s an urgent need for innovative infrastructure solutions that not only connect people, goods and services while facilitating trade, but also make strides towards minimising harmful environmental impacts, boosting resilienceand promoting more sustainable practices. This means taking a smarter approach to fixed infrastructure (including roads, railways, airways, waterways, airports and bus stations) and vehicles (cars, buses, trains, aircrafts, ships, etc.), as well as logistics and operations.
Smarter infrastructure for sustainability
A sustainable transport system involves many elements, including logistics, vehicles and fixed infrastructure. Metals, minerals and other raw materials are indispensable as building materials for everything from more basic facilities, such as roads or shipping containers, to more sophisticated solutions, including autonomous cars and smarter traffic control systems.
Railways provide essential connectivity between urban and rural areas, adding speed and efficiency to a country’s progress. Rail usage is rising, with total rail journeys doubling in the UK over the past 20 years. In China, there were 9,090 million passengers in 2015. Not only do trains transport people, but they are a means of moving materials that would not be possible using road vehicles. There are also environmental benefits of railway use, with cargo by rail resulting in an 80% decrease in CO2 emissions per kilogram in comparison to road haulage.
Modern railway technologies wouldn’t be made possible without metals and mined materials. Today, railroad tracks are made of parallel rolled rails, made from steel alloys, subject to international standards. They must be able to withstand both heavy loads and high speeds – achieved by the addition of carbon and manganese. Rails are connected by sleepers made of timber, concrete or steel, set into gravel or ballast for stability. Freight cars or goods wagons are usually made from aluminium alloys due to their mechanical strength, flexibility and resistance to corrosion – achieved through the addition of magnesium, chromium and/or silicon.
Roads are a primary facilitator of economic growth, health, education, and equality. Around the world, they comprise the backbone of transport infrastructure – yet a lack of roads remains a key impediment for the development of low-income countries, and hence an associated cause of poverty. Roads are reliant on both financial investment and natural resources. A road could not be built without metals, minerals, and other geological materials – primarily asphalt and concrete. Asphalt, also known as bitumen, is a sticky, black liquid form of petroleum. It can occur naturally, or be produced through refining. Concrete is made from air, water, cements (comprising calcium, silicon, aluminium, iron and other ingredients), supplementary cementing materials (eg fly ash, slag cement, silica fume), aggregates (eg sand, gravel, crushed stone) and chemical admixtures.
Intermodal freight involves the transportation of cargo in a standardised shipping container that can be moved between trains, ships or trucks without handling the freight itself. This enables transport systems to be more efficient, cost-effective and sustainable, by combining the advantages of each transport mode. It also allows for greater choice of transport routes and optimal logistics in terms of time, cost, and distance. From an operational perspective, intermodal transport requires a container – a large standard size metal box into which cargo is packed. These containers are designed to be moved easily and quickly, using common handling equipment. While consisting of relatively few parts (roof, side walls, floor, cross members, top/bottom rails, and corner posts), their role in intermodal freight is indispensable. The roof and side walls of a container are made of corten steel sheets, with corrugated profiles for strength and rigidity.
Cars are mostly owned and used by just one person, and parked for 94% of the time – representing poor use of resources. Automation (combined with shared ownership models) offers a viable solution to this issue. Autonomous cars, also called self-driving cars or driverless cars, maximise usage, increase efficiency and reduce congestion. Other benefits include reduced infrastructure costs, fewer traffic collisions and less need for parking space. These vehicles rely on hi-tech tools such as radar, laser lights, odometry instruments, computer vision and control systems, as well as global positioning systems (GPS) to track the vehicle’s positioning, movements and speed. GPS systems are dependent on satellites, usually comprising an antenna (made of copper, aluminium or stainless steel) and a power source (a battery or a solar panel). Metals in solar panels include silicon, aluminium, iron, lead, nickel, copper, cadmium and zinc, while silicon is also essential to satellite electronics.
The production of the car itself requires a range of non-renewable raw materials, including iron for body frames, molybdenum in airbags, or lithium for hybrid vehicle batteries. Other metals and minerals include steel, iron, magnetite, hematite, copper, nickel, chromium oxide, lead, carbon, bauxite, magnesium, platinum, rhodium, palladium. Ideally, such materials should be reclaimed and re-purposed at the end of a vehicle’s life, in accordance with the circular economy approach.
Electric cars are estimated to make up 55% of all new car sales globally by 2040. This is environmentally promising, as electric vehicles produce fewer carbon emissions than diesel vehicles – lowering air pollution and mitigating climate change. The main materials used in such vehicles are steel, aluminium, carbon fibre reinforced polymer (CFRP) and cast iron. Electric vehicles are powered by lithium-ion, nickel-metal hydride, or lead-acid batteries. These require lead alloys with small quantities of antimony, calcium, tin and selenium, nickel, rare earths (lanthanum, cerium, neodymium, and praseodymium), cobalt, manganese, aluminium, and lithium. They may use rare earth permanent magnets within their motors (containing neodymium, praseodymium, dysprosium and terbium). Rare earths can also be found in headlights (neodymium), LCD screens (europium, yttrium, cerium), glass and mirrors polishing powder (cerium), as well as in catalytic converters (made of cerium and lanthanum). Materials used in charging stations for electric cars include aluminium alloys, copper and steel, while sensors within energy meters are made from steel, brass, aluminium, and magnesium.
Sustainable infrastructure in cities is not only about autonomous or electric vehicles, but also traffic flow and control – in which smart traffic management systems can play a key role. A smart traffic control system combines traditional traffic lights with artificial intelligence and innovative ICT solutions. Such systems can reduce idling time at traffic lights by 40%, travel times by 25%, and CO2 emissions by 21 percent. They may also provide information directly to road users on how to minimise waiting times. Traffic lights are composed of an outer body of corrosion-resistant aluminium, supported by poles of strong galvanised steel. Electrical components are joined with copper wiring, while the lights rely on sensors to provide information on the current traffic situation. These sensors are made up of a transducer, comprising six separate components: piezoceramic element, housing, acoustic window, encapsulating material, sound absorbing material, and cable – built of a range of raw materials, including steel, brass, aluminium, and magnesium.