Actor and presenter Waseem Mirza was upset when he realized he had to replace his phone, especially since it was working so well.

Although the hardware worked smoothly, Samsung discontinued security updates for the phone in 2020. "I just wish there was a way to get more out of this old technology."

"I think the lack of (security) updates is very silly, really," said Mr. Mirza, who bought the phone in 2016.

"Your battery and screen are still running fine. You feel as though the manufacturer is forcing you to upgrade."

He uses his phone to manage his online banking, including that of his production company. "It's very important to me to have the latest critical software updates," he said.

In addition to the financial costs, upgrading your phone also comes with environmental costs. About 80% of carbon emissions Produced during the manufacturing process of mobile phones. This is called embedded or embedded carbon.

So from an emissions perspective, the longer phone users have access to the latest software to keep their phones running, the better.

An operating system called /e/OS may be the answer Mr. Mirza is looking for. It's a free version of Android that can extend the life of devices that no longer get updates, providing a potentially greener alternative to manufacturers' own software.

Mr. Mirza's old phone is among more than 200 supported devices, some of which are 10 years old. When support for the Galaxy S7 Edge ends next year due to hardware limitations, /e/OS will extend the life of the phone for another five years.

Gaël Duval, founder and developer of /e/OS, said: "We provide /e/OS for devices that have not been supported by their manufacturers for a long time."

"We try (to make them) receive all the latest security updates. The big manufacturers put a lot of bloatware on the phones and people don't use this useless stuff. That makes things slower over time. We've made the software lighter so it can run efficiently on older devices."

Manufacturers have been steadily extending the support life of new phones. For this year's Galaxy S24 phones, Samsung has extended support to seven years, in line with Google's commitment to its Pixel devices. Apple will support iPhone 16 for at least five years.

"Because of the current (processor) architecture and memory size of these new phones, they will likely remain available for a long time, possibly well beyond seven years," /e/OS COO Rik Viergever said.

In addition to allowing equipment to run longer, the software can also increase carbon efficiency while running.

Mobile applications must be energy efficient because mobile phones have limited battery power.

But many software runs on servers in data centers, and data centers have no such limits on power consumption.

"When you build a server application, you don't even think about how much power is used, so you don't do anything to optimize that," said Asim Hussain, executive director of the Green Software Foundation. "There are almost no tools to measure it."

The Software Carbon Intensity (SCI) specification helps measure the carbon footprint of software, and earlier this year, Become a global industry standard. The core of the calculation includes the emissions from running the software and the embodied carbon of the hardware it runs on.

The idea is to create a carbon intensity score that software developers can use to track their progress in trying to reduce the emissions of their software.

The specification was created by the Green Software Foundation, which has more than 60 members, including Microsoft, Intel and Google.

"We describe green software as software that is energy-saving and hardware-efficient, meaning it uses the least possible physical resources and therefore has fewer embodied emissions," Mr Hussain said.

"We also include carbon awareness, which means doing more when the electricity is clean and doing less when the electricity is dirty."

However, working out the fraction is far from simple.

"Calculating (SCI) is very difficult," Mr Hussain admitted. "The problem is a lack of data."

To help fill this gap, the Green Software Foundation created a set of models called the Impact Framework. It takes observations of things you can see, such as the percentage of server resources being used, and converts that into an estimate of carbon emissions.

What advice does Mr. Hussain have for chief technology officers? "Believe that if you give your team a performance metric like SCI, they will know what needs to be done to optimize it. You may get it wrong the first time, but be as transparent as possible and get feedback."

To help developers make their software more energy efficient, the ecoCode project is compiling a series of "code smells." These imply that the code might be able to use fewer resources, such as by replacing one instruction with another that does the same job faster.

"This is still an area that needs a lot of research," says Tariq Shaukat. He is the CEO of Sonar, which makes the code analysis software used by the ecoCode project.

"A lot of (code smells) are overly complex code. The second (type) is things that run in an inefficient way: you update or pull data more often than you need to. The other is bloat. How do you application as streamlined as possible?”

Peter Campbell is Director of Green Software at Kainos, an IT services company that builds cloud-based software for its clients. The company has used resources from the Green Software Foundation to train 500 engineers, product people and designers. Free short courses.

“We thought if we educate internally and externally, all of our teams will magically adopt it,” he said.

“It turns out it’s not that simple how it works. The culture part is really hard, not only getting people to take action but also keeping the priorities straight. Our customers have so many priorities, so sustainability sometimes isn’t the loudest ”

Information Technology and Communications (ICT) Department Estimated to account for 1.4% of greenhouse gas emissions in 2020. but, A 2018 study estimated By 2040, ICT will account for 14%.

There are signs that big companies are taking the issue more seriously.

According to Gartner analysts, although only 10% of large global enterprises currently incorporate software sustainability into their requirements, this proportion will rise to 30% by 2027.

Mr Hussain added that software was easier to decarbonise than many other industries, such as aviation. "We should push that button now because we can."