At the heart of the climate change problems the world is experiencing are greenhouse gas emissions into the atmosphere. Climate change is primarily caused by the accumulation of greenhouse gases in the atmosphere due to human activities. These absorb heat from Earth’s surface, warming the atmosphere.

New Zealand’s emissions mainly come from fossil fuels that emit carbon dioxide, and agriculture which emits methane and nitrous oxide. Statistics New Zealand says that in 2016, road vehicle emissions made up 39.1% of all our carbon dioxide emissions, manufacturing and construction emissions 19.7% and electricity generation 8.8%. The energy sector produced 87.5% of all carbon dioxide emissions. Methane from livestock digestion made up 35.3% of gross emissions in 2016.

Our net greenhouse gas emissions rose 54.2% from 1990 to 2016 due to more trees being cut down and an increase in gross emissions.

Greenhouse gas emissions are reported in carbon dioxide equivalents units – which is a measure for how much global warming a given type and amount of greenhouse gas causes, using the equivalent amount of carbon dioxide as the reference. This allows consistent reporting of different greenhouse gases.

That said, let’s move from the roads and paddocks of New Zealand to the things which have revolutionised workplaces in the last four decades – laptops, email and the internet. Sitting inside and probably using these every day, are you doing anything which has an impact on climate? The answer, of course, is yes. In 2010 Mike Berners-Lee produced a book called How Bad are Bananas: The Carbon Footprint of Everything. This has become a much-referred to source of information. While it’s still used to state “facts” on emissions, it’s nearly a decade old now. Our investigations have attempted to use more up-to-date sources, but some of these still draw on his research.

Email

Mike Berners-Lee worked out that the average spam email has a footprint equivalent to 0.3 grams of carbon dioxide emissions. A normal email has a footprint of 4 grams of CO2 emissions – calculated from the power data centres and computers required to send, filter and read a message.

“While the act of responding to and sending emails is often labelled as a mundane, tedious chore, it contributes significantly towards one’s carbon footprint because computers, servers and routers must expend energy to send, read and filter emails,” says Ahyoung Kim-Lee of Cornell University’s Roosevelt Institute (“Is Email Bad for the Environment?”, 5 March 2017 on the university’s website). “Emails with a large attachment can have a footprint equivalent to 50 grams of carbon dioxide,” she says.

To put it into perspective, the average passenger vehicle emits 411g of carbon dioxide per mile – so driving one mile (1.6km) is roughly equal to sending 8.22 emails with attachments or 102.75 “regular emails”, says Ahyoung Kim-Lee. The average US business user in 2016 sent and received an average of 123.9 emails per day, and 45,224 emails a year – annual email use in terms of carbon emissions equivalent to driving 180km.

“If the 62 trillion spam messages sent out annually are eliminated, 20 million tons of carbon dioxide could be prevented from entering the atmosphere.”

Websites

“A typical website produces 6.8g of carbon emissions every time a page loads… That’s roughly the same as the emissions produced when you boil an electric kettle for a cup of tea,” said erjjio studios managing director Ben Clifford in March 2019. His company is an environmentally-focused web hosting, design and developer based in London.

“We all know of the typical contributors to our own individual carbon footprint – for example, air travel, the food we choose to eat, the type of car we drive (and how much it’s used instead of public transport), and the energy provider we choose for our home,” he said in a blog post, “The alarming environmental impact of the internet and how you can help”.

“But we never stop to think that we view, save and exchange an endless stream of data every day – photos, videos, emails, music, messages, documents, presentations and countless other formats.

“This daily lifestyle is powered by a vast network of tangible, physical infrastructure – from data centres to transmission networks to the devices we hold in our hands, place in our laps and have on our desks. The transfer and mass storage of our data is enormous, and growing at a rapid speed.”

Mozilla’s 2018 Internet Health Report says if it were a country, the internet would be on track to become the fourth largest CO2 emitter on Earth after the US, China and India by 2025.

“The internet’s data centres alone may already have the same CO2 footprint as global air travel,” says the report, and explains that “a common convenience like switching lights on by speaking to a digital assistant creates a chain of reactions beyond your home, from one data centre to another, as information travels back and forth.”

Back to Ben Clifford, because he has some useful suggestions for reducing personal footprints:

• Delete emails that you won’t need again, to prevent them being stored unnecessarily.
• Unsubscribe from email newsletters and mailing lists that you never read.
• Delete apps on your phone that you don’t use.
• Delete redundant screenshots and photos from iCloud or other cloud drives.
• Use your phone for quick Google searches instead of a laptop – it uses less energy.

And if you’re worried about your own website, the Green Web Foundation maintains a directory of all the world’s services, data centres and hosting providers which are known to use 100% renewable energy. You can plug the address of any website in and check it. Another check at WebsiteCarbon will show how much carbon dioxide your website produces (you need to disclose visitor numbers).

Laptops

While your laptop is being made it will draw upon several rare-earth metals. These are mined in China, which accounts for 97% of the world’s rare-earths supply. “Relative to other consumer goods, laptops do not consume much electricity, but they still have a carbon footprint,” the Sciencing website says. “The University of Pennsylvania estimates that, depending on the model, laptops usually consume between 20 and 50 watts per hour of moderate activity. Even a laptop at the highest end of power consumption – using 80 watts per hour – would only produce 5g of carbon per hour of use.”

So, leaving your laptop on for an eight-hour stint means you will emit 0.4 kg of carbon into our planet’s atmosphere. For a 10-person office, that’s 4kg a day, 20kg a week and 960kg a year (with a four-week holiday). Not quite a tonne, but getting close…

Laptops are “significantly greener” than desktop computers, says Sciencing. “Desktops use much more electricity and therefore produce more carbon per hour than laptops.”

The manufacturers of all types of computers are, of course, very aware of the enviromental impact of their products. In 2010 Dell calculated that a “typical business laptop from Dell” – the Latitude E6400 – emitted a total of 350kg of CO2 equivalent over its whole lifecycle. This varied according to country, but went from manufacturing, transport, use and then recycling (assuming 75% was recycled and the rest incinerated). HP produces Product Carbon Footprint Reports. The HP 250 G7 Notebook PC was estimated this year to have a carbon footprint of around 275kg of CO2 equivalent during its life.

To end with a hopeful piece of news. In May 2019, UK-based Circular Computing (a brand of A2C Services Ltd) announced that it is producing the world’s first remanufactured carbon-neutral laptops (“World’s first carbon neutral laptops”, The Recycler, 15 May 2019).

“The IT industry causes as much greenhouse gas pollution as the entire airline industry, with figures rising as internet usage soars,” says Circular Computing. “More than 160 million new laptops are made every year, responsible for around 17% of electronic waste, and production depends on many of the earth’s dwindling resources, including rare ‘conflict’ minerals, metals and water.”

Instead of being refurbished, the laptops are completely re-built. “They cost around 40% less than their equivalent new top-brand laptop, and the company re-purchases the laptops every three years to re-join the remanufacturing process and be redeployed to other areas where they remain fit for purpose. In total, the company estimates three re-loop cycles and another nine years of useful life, which in turn creates enormous positive environmental, ethical and social impact.”

Circular Computing – which plants five trees for every laptop sold – has signed a contract with Fortune 200 company Synnex.