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Tech for a sustainable future: The challenges and opportunities ahead

We need to build and use technology more sustainably, and deploy it more effectively in the fight against climate change.
Written by Charles McLellan, Senior Editor
Earth & climate change
Image: Getty Images / Surasak Suwanmake

Fifty years ago, in 1973, the world was a very different place. For one thing, there were just under 4 billion people on the planet in that year (I was one of them, aged 17), compared with an estimated 8 billion today – a 100% increase in half a century. The UN's latest projections suggest that the global population could grow to around 8.5 billion in 2030, 9.7 billion in 2050, and 10.4 billion in 2100. 

The resources consumed and emissions created by this greatly expanded population -- particularly those who live in the developed world and plant the biggest ecological footprint -- are the cause of climate change and biodiversity loss that could pose an existential threat to human civilization. 

In 1973, Earth Overshoot Day -- the date when humanity's demand for ecological resources and services in a given year exceeds what Earth can regenerate in that year -- fell on 1 December. In 2022, it was 28 July. 

Technology has changed beyond all recognition during the past 50 years. Back in 1973, mainframes and minicomputers still ruled the roost, with personal computers barely off the drawing board -- the MITS Altair 8800 was a year away, while the Apple I didn't appear until 1976. The entire Internet – then known as ARPANET -- could be mapped out on a single piece of paper, and later that year made its first international connection (to Norway), while the World Wide Web wouldn't appear until 1989. The first ever handheld mobile phone call was made by Motorola's Martin Cooper in New York on 3 April 1973 on a handset weighing 4.4lbs (2kg). Many other examples of startling progress over the past half-century could be cited for other tech sectors. 

What is consistent across this 50-year timeframe is that technological advancement does not in itself mitigate the effects of population increase and the distribution of resource consumption -- quite the opposite, in many respects: much of the tech created and used over the past 50 years has contributed significantly to global warming.

Warning signs are now flashing all around the globe: the past eight years were the eight warmest on record; the past 2.5 years account for 10% of overall sea level rise since the start of satellite measurements nearly 30 years ago; record-breaking heatwaves were observed in many nations in 2022; and rainfall has been consistently below average in some areas (East Africa) and unprecedented in others (Pakistan).

As the IPCC states in its Climate Change 2022: Impacts, Adaptation and Vulnerability report: "Global warming, reaching 1.5°C in the near-term [2021-2040], would cause unavoidable increases in multiple climate hazards and present multiple risks to ecosystems and humans".

Are we smart enough to deploy technology more effectively to help create a more sustainable global economy, and can we build and use technology more sustainably?

These are the main questions covered, from various angles, in this ZDNET in-depth special report. In the meantime, here's some more context.

What is the fate of technological civilizations?

In his excellent and accessible 2018 book Light of the Stars, Adam Frank, a professor of astrophysics at the University of Rochester, describes a mathematical model of how theoretical technological civilizations might respond to changing conditions on their planets. For simplicity, the model includes just two kinds of energy resources -- one with high planetary impact (like fossil fuels), the other with low impact (like solar energy). At some point, rising planetary temperature causes a civilization to switch energy resources from high to low impact, and the model explores various outcomes for the planet's capacity to support a population of the energy-consuming species. 

Light of the Stars: model planets

Trajectories for population and planetary temperature on theoretical worlds under different conditions.

Image: W W Norton, from Light of the Stars by Adam Frank

After running multiple simulations, three kinds of trajectory were observed: 'die-off' (A, above), where the population increases, overshoots the planet's carrying capacity, and then reduces until planet and civilization reach equilibrium; the 'soft landing' (B, above), where an early switch to the low-impact energy resource allows a smooth transition to a sustainable equilibrium without overshoot or die-off; and 'full-blown collapse', both without energy resource switching (C, above) and, in some cases, with switching, but too late (D, above). In the latter scenario, Frank writes: "Once the ball got rolling, the planet's own internal machinery took over. It wasn't coming back to the original climate state, and it took the civilization down with it as it ran away into a new state". 

Of course, we don't know which, if any, of these trajectories Earth and its human population might follow (although high-resolution next-generation climate models based on exascale computing will help), but the warning signs are there, and it would certainly be wise to avoid dicing with the tipping points that can lead to full-blown collapse.

However, global emissions are still too high: the IPCC estimates that 410 gigatonnes of CO2 were emitted between 2010 and 2019, leaving a 'carbon budget' of just 500GtCO2 for the remainder of the 21st century to limit global warming to 1.5°C. As of November 2022, global temperatures were about 1.2°C above pre-industrial levels and heading for 2.4°C by 2100 under current 2030 targets.

How does technology contribute to climate change?

Climate Action Tracker
Image: Climate Action Tracker

The environmental impact of ICT (information and communication technologies) has been covered in detail by The Shift Project, a French think tank that advocates a shift to a post-carbon economy, in a trio of detailed reports: Lean ICT - Towards Digital Sobriety (2018); Climate Crisis: The unsustainable use of online video (2019); and Implementing digital sufficiency (2021). 

The headline conclusion from the Lean ICT report was that digital technologies -- telecoms networks, data centers, terminals and IoT sensors -- accounted for 3.7% of global greenhouse emissions in 2018 (up from 2.5% in 2013), with energy consumption increasing by 9% a year. Just over half (55%) of digital technology's energy consumption came from its use, and just under half (45%) from its manufacture. 

A 'sober digital transition', as The Shift Project calls it, could be achieved by "buying the least powerful equipment possible, in changing them the least often possible, and in reducing unnecessary energy-intensive uses". This could reduce growth in energy consumption from 9% per year to 1.5%, the think tank estimated, while noting that this is still not compatible with Paris Agreement objectives.

Further efforts will clearly be required to reduce the environmental footprint of digital technology, especially in the developed world: in 2018, the average American owned 10 digitally connected devices and consumed 140GB of data per month, compared to one device and 2GB/month in India, The Shift Project said. 

Also: This giant geothermal plant is surrounded by lava. It could help solve tech's energy problem

The think tank's second report concentrated on online video, which, it estimated, generated 60% of world data flows and 300 million tons of CO2 in 2019, or 1% of global emissions. Four main types of online video content were identified: video on demand (e.g. Netflix, Amazon Prime, 34%); pornography (27%), 'Tubes' (e.g. YouTube, Dailymotion, 21%); and others (e.g. video hosted on social networks, 18%). Mitigating the environmental impact of online video would mean reducing the use and size of video files, and regulation of different types of usage, the report argued.

A key component of any sustainable digital transition will be a move to a more circular economy, where instead of manufacturing, using, disposing of and replacing tech products, device lifetimes are extended via repair, refurbishment and reuse, and component materials re-enter the (ideally closed-loop) process via recycling rather than becoming e-waste and going to landfill, causing pollution and requiring replacement minerals and metals to be extracted (resulting in further environmental damage).

What are companies doing to improve sustainability?

Check the websites of most large companies and SMEs, and you'll find statements, with varying levels of detail, extolling their environmental and social responsibility and commitment to increased sustainability across their supply chains.

These sentiments are evident in a regular report from research firm IoT Analytics, which does keyword analysis on the quarterly CEO earnings calls of some 1,500 US-listed companies. In its Q3 2022 report, sustainability was discussed by 21% of CEOs, along with climate (14%) and emissions (13%), continuing a long-term positive trend since 2019 -- albeit with dips in early 2020 and Q3 2022 when discussion about the transition to a more sustainable economy was temporarily overridden by concerns about the COVID-19 pandemic and economic uncertainty respectively.

IoT Analytics: sustainability trend
Image: IoT Analytics

IoT Analytics notes that "most CEOs seem convinced that the push towards more sustainability [will] be beneficial for their enterprises" -- a view supported by a November 2022 Gartner survey, which found that 87% of business leaders expect to increase their organization's investment in sustainability over the next two years, with the main drivers being customers (80%), investors (60%), and regulators (55%).

Further support for the value of investing in sustainability comes from an early 2022 report by the Deloitte Economics Institute entitled The Turning Point: A new economic climate in the United States. This suggests that if global warming reaches around 3°C by 2100, "economic damages would grow and compound, affecting every industry and region in the country," making it "harder for people to live and work due to heat stress, rising sea levels, damaged infrastructure and reduced agricultural productivity". 

Also: Business travel, energy consumption in the spotlight as sustainability jumps up the agenda

Deloitte's analysis suggests that insufficient action on climate change could cost the US economy $14.5 trillion over the next 50 years, with the loss of nearly 900,000 jobs each year. By contrast, the report argues, rapid decarbonization over the same period could add $3 trillion to the economy and nearly 1 million jobs by 2070. The UK government's recent Net Zero Review comes to a similar conclusion: "Delivering net zero is the industrial revolution of our time -- and climate change the greatest threat...we must grab this opportunity, there is no future economy but a green economy". 

Economic incentives, driven primarily from the ground up by customers, will give companies the impetus to invest in sustainability. But what specific actions can they take in order to decarbonize and move towards more sustainable operations? One route is by signing up to the Science Based Targets initiative (SBTi).

A partnership between CDP, the United Nations Global Compact, World Resources Institute (WRI), and the World Wide Fund for Nature (WWF), SBTi, which also collaborates with the We Mean Business Coalition, defines and promotes best practice in reductions of greenhouse gas emissions and net-zero targets, provides technical assistance and resources to companies wishing to set science-based targets, and convenes a team of experts to provide companies with independent assessment and validation of targets. All for a price, of course (although discounts for SMEs and exemptions for some companies in developing countries are available).

The SBTi currently has 4,382 companies taking action on climate change, 2,141 of them with science-based targets and 1,625 with net-zero commitments. So, how are the top tech companies doing when it comes to being good climate citizens? 

We took the top 20 technology companies in the Forbes Global 2000 and examined their near-term, long-term and net-zero SBTi status: 


Forbes Global 2000 rank 

SBTi near-term target status 

SBTi long-term target status 

SBTi Net Zero status 






1.5° (2030) 










1.5° (2030) 










1.5° (2030, 2035) 





1.5° (2024, 2030) 








China Mobile 





Alibaba Group 





Facebook (Meta) 












1.5° (FY2030/31) 





1.5° (FY2035) 

1.5° (FY2040) 







Deutsche Telekom 


1.5° (2030) 





1.5° (2030) 





1.5° (FY2030) 

1.5° (FY2040) 












Generally speaking, the world's top tech companies are good climate citizens: 14 out of the top 20 (70%) have signed up with SBTi -- five expressing their commitment to setting science-based targets and nine with near-term targets already set (all aiming for reductions consistent with 1.5°C, most by 2030). Eight of the top tech companies are either committed (6) or targeted (2) to achieve net-zero status in the long term.

Although it's not in the top 20 listed above, Lenovo recently announced the validation of its commitment to reach net-zero GHG emissions by 2050 -- "the first PC and smartphone maker and one of only 139 companies in the world with a net-zero target validated by SBTi," the company claims. Lenovo has had validated near-term targets (1.5°C / 2030) since 2020.

There are six absentees from SBTi among the top 20 tech companies, but that doesn't mean they are dragging their heels on climate change. Samsung is committed to enterprise-wide net-zero status by 2050, Intel by 2040, TSMC by 2050, IBM (impressively) by 2030, and Oracle by 2050. China Mobile, meanwhile, has a wide-ranging green and low-carbon operations plan. Also, although Apple, for example, does not have a formal SBTi net-zero commitment or target, the company has a clear policy to make all of its products carbon neutral by 2030.

Further evidence of commitment to sustainability comes from leading PC and device manufacturers -- including Lenovo, HP, DellApple, and Samsung -- who are all increasingly embracing sustainable and recycled materials, designing more modular and repairable products, and pledging to minimize e-waste. 

HP 27-inch All-in-One PC

Announced at CES 2023, HP's latest 27-inch All-in-One PC uses 40% post-consumer recycled plastic in the enclosure, 75% recycled aluminum in the stand arm and neck, and 100% recycled polyester in the felt base cover.  

Image: HP

Then there are smaller vendors such as Fairphone and Framework, which specialise in modular phones and laptops respectively. There's also a growing market for refurbished PCs, with a 2021 valuation of $9.34 billion, rising to an estimated $14.76bn (6.8% CAGR) by the end of 2027. We should always be wary of greenwashing, of course, but it does seem as though technology companies are now paying a lot more than lip service to the environment.

The road ahead

As the world's population heads towards 10 billion-plus in 2100, the window of opportunity for limiting global warming to 1.5°C, per the 2015 Paris Agreement, is closing rapidly. Technology has contributed significantly to global warming over the past 50-plus years, but tech companies are increasingly signing up for verifiable, science-based emission-reduction targets, and embracing sustainable and recycled materials, designing more modular and repairable products, and pledging to minimize e-waste. Innovation in areas like carbon capture, renewable energy, battery technology, the Internet of Things, and remote sensing will also have a big part to play in climate mitigation going forward.

News on climate change can seem relentlessly bad, but there are grounds for hope. In January this year, the UN announced that the Earth's ozone layer, which protects the planet's inhabitants from harmful ultraviolet rays, was on track to recover to 1980 values within four decades. This marks the success of the 1987 Montreal Protocol, which regulated the production and consumption of ozone-depleting substances such as CFCs (chlorofluorocarbons).

"Ozone action sets a precedent for climate action. Our success in phasing out ozone-eating chemicals shows us what can and must be done -- as a matter of urgency -- to transition away from fossil fuels, reduce greenhouse gases and so limit temperature increase," said Petteri Taalas, secretary-general of the World Meterological Organization (WMO).

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