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Beyond energy: the main offenders for climate change

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Energy production has the most impact on the environment in terms of greenhouse gas emissions, but what are the other ‘main offenders’? We look at four other sectors – transport, manufacturing and construction, agriculture and industrial processes – to see how they are adapting.

Transport and climate change: driving up the figures

Emissions from the worldwide transport sector are a major contributor to climate change, producing 14 per cent of annual emissions (including non-CO2 gases). “More concerning,” says the World Resources Institute, “at a time when global emissions need to be going down, transport emissions are rising,” with sector analysis made more complex by the fact that improvements in vehicle efficiency are often offset by greater overall volume of travel.

Major problem 1: Highway to hell?

Maybe not, but the picture is ambiguous, with some factors offsetting others. So while reducing emissions from road transport in the UK remains “a significant challenge as the UK looks to reach zero net emissions by 2050”, by the end of 2018 only 0.5 per cent of all vehicles licensed in the UK were ultra-low emission vehicles. According to the Office for National Statistics, in the three decades leading up to this statement, road travel had increased from 255 billion miles to 328 billion miles, while fuel consumption remained stable due to increased fuel efficiencies, with petrol use in decline, offset by an increase in diesel. While greenhouse gas (GHG) volumes produced by road traffic have remained relatively stable (effectively dropping relative to the increase in road traffic) at just over 100 MtCO2e (increasing by 6 per cent), they now account for an increased proportion – one-fifth – of the UK’s total GHG emissions, as other sectors play a part in an overall decrease.

Major problem 2: Crowded skies

The Air Transport Action Group says that in 2019 worldwide flights produced 915 MtCO2e, meaning that the global aviation industry generates 2 per cent of all human-produced CO2 emissions, while accounting for 12 per cent of the transport sector. According to airliners.net, there are currently 39,000 passenger and commercial aeroplanes in service globally (not counting light aircraft), transporting 4.5 billion people annually. Prior to the Covid-19 global health crisis, the International Civil Aviation Organisation stated that the global air transport network “doubles in size every 15 years, and will do so again by 2030”, bringing the projected total to well over 60,000. While it is too soon to tell what the long-term effect of the pandemic will be, according to the website Carbon Independent, airliner emissions remain at quarter of a tonne of CO2 per hour in the air.

Major problem 3: Too many tourists

Despite the fact that global tourism took a massive hit in 2020 – with the UN World Tourism Organisation stating an annual decline of “between 60 and 80 per cent when compared with 2019 figures” – most UNWTO Panel Experts “expect international tourism to recover by the second half of 2021”, with a rebound in domestic tourism happening sooner. A recent study – The Carbon Footprint of Global Tourism – shows long-term predictions of an annual 5 per cent increase in world tourism, the sector that accounts for 8 per cent of GHG emissions, creating the likelihood of Covid-related impacts being a blip.

What can be done?

United Nations Economic Commission for Europe says that to achieve sustainability, CO2 abatement and improved fuel efficiency in the transport sector needs to be addressed from five positions including: new vehicle technologies, the use of sustainable biofuels, improved transport infrastructure, better public outreach (such as campaigns for improved eco-driving) and legislation.

With 70 per cent of the flights taken in the UK by only 15 per cent of the population, Greenpeace argues that, since air travel is effectively a luxury for the wealthy, an effective way to reduce traffic and reduce CO2 emissions is to bring in a frequent flier levy.

Manufacturing and construction and climate change: building a future

Both the manufacturing and construction industries have heavy impacts on the emission of greenhouse gases. While manufacturing has embraced ‘lean’ techniques and ‘closed-loop’ supply chains to drive down waste and optimise efficiency, developing green credentials can also have a positive effect on the bottom line. Meanwhile, construction is under pressure not only to reduce the carbon footprint of new buildings, but also to decarbonise existing ones.

Major problem 1: Building priorities

According to the UK Green Building Council, 10 per cent of the country’s carbon dioxide emissions are directly associated with construction activities. This figure rises to 45 per cent when the entirety of the built environment sector is taken into account. With 80 per cent of all buildings that will be in existence in 2050 already having been built, “a major priority is decarbonising our existing stock”. While the definition of the industry’s contribution to overall GHG emissions varies depending on whether ‘in use’ burdens are applied, the ‘low-carbon route map’ for meeting obligations under the 2008 Climate Change Act is based on a reduction from the 2014 UK figures of 185 MtCO2e (or 22 per cent of the UK’s overall emissions), to 113 MtCO2e by 2025, leading to 45 MtCO2e by 2050. The UN Environment Programme says that the “most promising strategies” to achieve this are to “design with fewer or alternative materials”, and “more recycling of construction materials”.

Major problem 2: Manufacturing supply chain emissions

According to a study released by the Warwick Business School: “Supply chains contribute significantly to a firm’s carbon footprint and can amount to as much as four times the organisation’s own operational emissions.” The research concluded that when it comes to companies engaging with their supply chain to reduce carbon emissions, there are “three levels of activity with their supply chain – basic, transactional and collaborative”. Not surprisingly, it is those in the collaborative phase that are able to provide benchmarking to suppliers regarding their GHG emission reduction, in order to “identify sustainability improvement opportunities”. In 2017, Apple announced that it was “moving toward a closed-loop supply chain. One day we’d like to be able to build new products with just recycled materials, including your old products.” The tech giant further pledged that by 2030, “every Apple device sold will have net-zero climate impact”.

Major problem 3: Industry 4.0 to the rescue?

On the face of it, the Fourth Industrial Revolution, which will among other things digitalise the manufacturing production process, should have a positive effect on our ability to combat climate change. As the Industrial Internet of Things forces manufacturers to rethink the ecological footprint of their products and processes, and big data analytics influences cost efficiency, quality and production speed, industry should become greener as it progresses towards net-zero emission manufacturing and 100 per cent recycling. According to Climate-KIC, which aims to accelerate the transition to a zero-carbon, climate-resilient society, the problem is that, having “worked in a linear way for 150 years, there are almost no interconnected value chains in production industries at the moment”.

What can be done?

Construction Climate Challenge says that ways in which the industry can help to protect the environment are to incorporate eco-friendly recycled materials that produce less CO2, adopt green construction practices such as using alternative-fuel construction machinery, and maintain long-term ‘in use’ sustainable operations over a building’s lifetime through facilities management and maintenance education. In terms of supply-chain efficiency, one solution is to implement robust data analysis and audits of suppliers’ cumulative footprints.

Agriculture and climate change: a chicken and egg scenario

When it comes to analysing the impact agriculture has on climate change, one of the biggest differences between this industrial sector and others, such as energy production, is that the processes are interrelated. While the effects of anthropogenic emissions of greenhouse gases created by agriculture can affect the climate, the reverse is true in that aspects of climate change, such as average temperature and rainfall, can have a negative impact on agriculture.

Major problem 1: Intensive animal farming

Sometimes called ‘factory farming’, intensive animal farming is big business and accounts for 40 per cent of global livestock production. There are more than 800 so-called mega-farms in the UK alone, (to be classed as ‘intensive’, a farm must have warehouses with more than 40,000 birds, 2,000 pigs or 750 breeding sows). To give an idea of the scale, Herefordshire, with more than 16 million factory-farmed animals at any given time, has 88 times more headcount of livestock than it does humans. Leaving aside the hot-button question of ethics, farming on this level requires vast amounts of energy to sustain it. According to a study by the Royal Society, fossil fuels account for half of the total energy used in commercial agriculture. Only a quarter of this energy goes into rearing the livestock in terms of heating, lighting and ventilation, while the balance goes on feed production.

Major problem 2: It’s not just CO2

According to a report published by Defra’s Air Quality Expert Group – ‘Air Pollution from Agriculture’ – nitrogen-containing compounds are emitted to the atmosphere from agricultural activities. The main focus of the report is on ammonia (NH3), described as “an important contributor to air-quality issues in the UK”. In fact, agriculture produced 88 per cent of annual UK ammonia emissions in 2016. The report estimates that halving agricultural emissions of NH3 could reduce ammonia toxicity lung disease deaths globally by around a quarter of a million annually. In terms of environmental damage, the main effect of NH3 emissions “is its contribution to eutrophication due to nitrogen deposition on the semi-natural landscape”, creating damage in 63 per cent of sensitive habitats in the UK alone.

Meanwhile, nitrous oxide (N2O) is about 300 times more potent as a GHG than carbon dioxide. According to the United Nations, the meat, egg, and dairy industries account for 65 per cent of N2O emissions worldwide.

Major problem 3: Livestock emissions

It’s easy to see only the funny side of the problem, but according to Dani Rabaiotti, author of ‘True or Poo?’, methane released from both ends of a cow’s digestive tract makes up “nearly a third of all emissions from agriculture”. It’s a case of ‘you do the math’: with each of the world’s one billion cows producing 200kg of methane annually, that’s two billion tonnes of greenhouse gas being literally belched out into the atmosphere.

What can be done?

The Air Quality Expert Group says that 60 per cent reductions in nitrogen-containing emissions have been made in the Netherlands through strict regulation of manure management. Further improvements can be brought about by the adoption of low-emission mineral fertilisers.

Meanwhile, scientists in Wiltshire are developing battery-powered farm robots to replace diesel-guzzling tractors that can feed and weed crops, while drone topography scans reduce the need for nitrogen-based fertilisers by mapping and monitoring soil to determine correct locations and quantities.

Low-tech solutions include keeping cows outside for longer, so that they feed on grass rather than the 2.5 million tonnes of soya imported into the UK annually that has been grown on new agricultural land repurposed from rainforest.

Industrial process and climate change: more heat than light

Since the Industrial Revolution of the late 18th century, there has been a dramatic increase in global wealth and the standard of living. This shift has been driven by economies eager to exploit the demand for commodities such as iron and steel, cement, chemicals and petrochemicals, all of which require vast amounts of energy to produce. In fact, heavy industrial processes account for one-third of the world’s energy use, 70 per cent of which comes in the form of burning fossils.

Major problem 1: A question of capital

Heavy industry creates 22 per cent of global CO2 emissions, with 40 per cent of that total coming from the combustion required to produce the high temperatures involved in processes such as steel making. This aspect alone accounts for more GHG than cars and planes put together, yet it doesn’t register highly on the media agenda.

While green domestic energy and transport policies can be affected by public opinion and consumer demand, public perception of heavy industry is far more limited. The problem with producing industrial heat is that it tends to be done in facilities that use equipment such as blast furnaces that have been designed to last for decades. As a result, current capital stock inhibits the rate at which new technologies can be adopted. According to a report by the Center for Global Energy Policy, deployment of replacement facilities and technologies remains ‘problematic’.

Major problem 2: Waiving obligations

Another critical aspect of industrial processes is that the end product – often a globally traded commodity – is vital to national economies, while the industry itself is prized for its ability to generate employment. This means that governments will tend to resist driving up production costs by over-burdening the manufacturer with legislation that forces the implementation of expensive alternative low-emission technologies, that could in turn run the risk of so-called ‘carbon leakage’. This is when companies decamp overseas in search of cheaper operating environments. The CGEP report says that this explains why industries routinely receive environmental waivers, “even in countries with stringent carbon targets”.

Major problem 3: Too much cement

According to think tank Chatham House, the cement industry is responsible for 8 per cent of the world’s entire CO2 emissions. Which means that if cement were a country, in the words of a BBC report, “it would be the third largest emitter in the world behind China and the US”. And emissions are forecast to increase as cement consumption escalates: China used more cement in the years 2011-13 than the US did in the entire 20th century. But it’s not all bad news: “Improvements in the energy-efficiency of new plants and burning waste materials instead of fossil fuels has seen the average CO2 emissions per tonne of output fall by 18 per cent over the last few decades,” says Chatham House.

What can be done?

The short answer is to stop using fossil fuels and related technologies in these processes and switch to low-emission alternatives. But before doing that, the Intergovernmental Panel on Climate Change (IPCC) maintains: “Through innovation, additional resources of up to 20 per cent in energy intensity may potentially be realised before approaching technological limits in some energy intensive industries,” (although it admits that the notion has only “limited evidence, medium agreement”). The IPCC makes a stronger case for “step-change options [that] can include a shift to low-carbon electricity, radical product innovations or carbon dioxide capture and storage”. The solution that meets the conditions of ‘robust evidence, high agreement’ is “improving plant efficiency with both energy savings and emissions benefits”.

All figures for this article were taken from reliable sources, but may not agree with those from other sources. In some cases, figures have been rounded into context statements such as ‘half’ or ‘a tenth’.

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