The carbon impact of steel and implications for home appliances

Alex Crumbie and Josie Wexler crunch the numbers on the enormous carbon impact of steel, along with other environmental and social impacts of producing steel for home appliances and infrastructure.

Steel has come to play a vital role in industrial societies and, as such, is produced at an incredible magnitude. In 2019, world crude steel production reached nearly 1.9 billion tonnes, up from 0.9 billion tonnes at the start of the millennium.

China produced 1 billion tonnes of crude steel in 2019, accounting for just over half (53%) of the global total. Next in line is India, which produced 6%, followed by Japan at just over 5%. The UK meanwhile, produced over 7 million tonnes, accounting for 0.4%.

It is an essential component of domestic appliances, but only 2% of the total steel produced is used for this purpose. The vast majority (52%) is used for building and infrastructure.

The carbon impact of steel

Steel has a heavy carbon footprint, primarily due to its energy-intensive and coal-reliant production process. For the most common method of steel production, blast furnaces are heated to temperatures around 1,300 degrees Celsius, requiring huge amounts of energy. Carbon is also needed, which comes in the form of coke (a form of coal), which is added to iron in order to increase its strength and hardiness.

According to scientist Mike Berners-Lee, global steel production produces 2.9 billion tonnes CO2e, accounting for up to 8% of the world’s CO2 emissions. It is therefore essential that changes are made to the industry in order to reduce its carbon impact. There are already ways of doing this, notably replacing coal with hydrogen in the manufacturing process, and increasing the use of recycled steel – the latter not only reduces carbon emissions but can also reduce iron ore mining. At present, on average, only 25% of steel is recycled globally.

Using figures from Mike Berners-Lee’s book, ‘How bad are bananas?’, we can see that these production methods greatly reduce the carbon impact of each tonne of steel produced.

Carbon emissions of steel production (figures from Mike Berners-Lee)
Production method Tonnes of CO2e
Virgin steel made in a blast furnace with coal 2.3
25% recycled steel 1.8
Virgin steel using hydrogen instead of coal 1.1
100% recycled steel 0.4

Steel and embodied emissions in appliances

Steel accounts for about half of the weight of dishwashers, washing machines and fridge freezers, which weigh in the region of 40-70 kg. You could do a rough calculation of the emissions from the steel in them from this, although it is complicated by the different types of steel. Stainless steel has at least double the greenhouse gas emissions of normal steel.

Total greenhouse emissions from manufacturing appliances are estimated at about 300-400 kg CO2e for fridges, washing machines are similar and dishwashers in the region of 200 kg. However, this needs to be spread over their lifetime – fridges last for about 15 years, washing machines and dishwashers about 12 years. 350 kg spread over 15 years is 23 kg per year.

Everyone agrees that the bulk of the greenhouse gases in the case of all of these appliances is expended during the usage stage. It is hard to find up-to-date figures, but studies from about 10 years ago estimate it at 80%, although given that they are getting more efficient and our electricity grid is decarbonising, it may be less than that now.

Here are some greenhouse gas figures for comparison:

  • UK average per person per year, including imported goods: 12 tonnes CO2e
  • 1 kg European beef: 39 kg CO2e
  • 1 kg bananas: 0.9 kg CO2e

What are home appliance companies doing about steel and carbon?

During our research for fridges & freezers, cookers and vacuum cleaners we found that the environmental and social impacts of steel were hardly discussed publicly by the appliance companies covered in these guides. Granted, they are not producing the steel but, as buyers of it, they have the ability to pressure steel manufacturers and a responsibility to minimise their impacts.

Only two companies were found to discuss the environmental impacts of steel in any depth: Miele and Electrolux. Both companies stated that they were working to increase the amount of recycled steel they used, the latter had also set targets in relation to this issue. It is essential that other companies follow suit.

The impacts of iron ore mining

Steel is primarily composed of iron, which is extracted from iron ore. In 2019, 2.85 billion tonnes of iron ore was produced, about 98% of which is used for steel making. In that year, the top three iron ore producing countries were Australia (930 million tonnes), Brazil (480 million tonnes), and China (350 million tonnes).

Iron ore mining, like most types of mining, has taken its toll on the natural environment. This is especially true in Brazil, where iron ore mines gnaw away at the ever-shrinking Amazon rainforest and a number of serious incidents have caused untold devastation.

flooded area in Mariana, Brazil from dam failure
Effects of the 2015 Fundao tailings dam failure in Mariana, Brazil

The Mariana dam disaster in Brazil occurred in 2015 when the Fundão tailings dam collapsed, releasing around 60 million cubic metres of iron ore waste into the surrounding area, killing 19 people, displacing hundreds, and contaminating the river. The company responsible for the disaster was Samarco, a joint venture between the Brazilian company Vale and the English-Australian BHP, which are the second and third largest iron ore producing companies in the world.

“Mariana, never again,” said Vale CEO, Fabio Schvartsman, in a speech in 2017, the day he became president of the company.

But, in January 2019, about 120 km west of the site of the Mariana dam disaster, the Brumadinho dam disaster occurred, killing at least 259 people and releasing 13 million cubic metres of iron ore waste and mud into the surrounding area. The dam was owned by Vale.

In 2020, Brazilian prosecutors charged 16 people over the incident, including the former CEO of Vale, with murder and environmental crimes and, in 2021, the company agreed to pay the equivalent of £5 billion to the communities affected.

Cumbrian coal and UK steel

Using hydrogen instead of coal in the production process greatly reduces the carbon impact of steel yet, in October 2020, local planning permission was granted for a new coal mine in Cumbria, UK, with the stated purpose being “to supply national steel and chemicals industries”.

The Cumbrian company involved claims that its coal is a vital ingredient in the steel-making process. However, planning documents reveal that UK steel manufacturers have said they would not be able to use coal from this mine because of its high sulphur content. The Daily Telegraph quotes Julian Allwood, a professor of energy and environment at the University of Cambridge, who states that; 'the market for coking coal is going to collapse, probably rapidly.'

The proposed deep coal mine near Whitehaven is the first facility of its kind to gain planning approval in 30 years, despite local objections and it undermining the UK Government’s carbon targets. The mine aims to remove 2.5 million tonnes of coal from beneath the Irish Sea every year for the production of steel in the UK and Europe.

The proposal was initially backed by the local Cumbria Country Council but, after criticism from environmental groups and warnings from the UK government’s own Climate Change Committee, the government backtracked on their initial refusal to intervene.

In a surprising u-turn, in mid-March Communities Secretary Robert Jenrick decided to ‘call in’ the controversial decision. An official letter stated that Mr Jenrick “believed the application had raised issues of ‘more than local importance’” and that “The Climate Change Committee’s recommendations for the 6th Carbon Budget have been published since he was advised on this decision. The Secretary of State ... considers that this should be explored during a public inquiry.”

Tony Bosworth of Friends of the Earth commented: “It was not possible for the government to maintain ... that this was just a matter of local importance and the decision will now rightly be taken at national level.' He also said:

“A new coal mine in Cumbria would not only wreck our climate, it would also destroy the UK government’s credibility ahead of crucial climate talks in Glasgow later this year”.

Cumbria Action for Sustainability (CAfS) simultaneously released a report titled ‘The potential for green jobs in Cumbria’. It calculates that “around 9,000 jobs could be created for local people during a 15-year ‘transition period’ towards the county reaching net-zero, and a further 3,800 jobs in the longer term across sectors including transport, industry, retrofitting, renewable heat, renewable electricity and waste”. Of these, 4,500 would be in West Cumbria, the site of the proposed Whitehaven coal mine.