The internet is an engine of information that runs on electric power, coursing through data centres, wire cables and connected devices to meet the demands of 5.3 billion users.

We take its functionality largely for granted - it’s only when we encounter a blindspot or spotty wifi that the web’s reliance on physical infrastructure comes abruptly into view. Occasionally, data centres overheat or run into configuration trouble, prompting outages of popular apps and also highlighting - albeit briefly - the engineering complexity that underpins our digitised century.

The obscurity in our daily lives of how the internet works is arguably a problem. Why? Because it obscures another fact that isn’t given much thought, namely that browsing the web burns energy.

Everything we do online consumes electricity, pushing carbon emissions into the air as billions of emails are sent, video meetings are hosted, and movies and music are streamed in millions of hours’ worth of entertainment.

There simply isn’t enough renewable energy to support all of this activity worldwide, and wind/ solar/ hydroelectric sources are also spread unevenly region by region. The exponential rise of smartphone use and the continuing globalisation of internet connectivity will meanwhile only increase the amount of data traffic.

Though we can observe these big-picture trends, it’s surprisingly hard to calculate the precise carbon cost of the internet. Data scientists are divided on where to set the limits. Should the manufacturing of phones and computers, a process that is implicitly carbon-intensive, be included? Is it good enough to estimate the output of a web page based solely on its data requests to a server? Or do we also need to consider the user device too, and encompass all these points together?

Anders Andrae, an expert in this field based in Stockholm, has focused his research on forecasting the web’s future electricity consumption. In a 2020 paper he wrote that “Most researchers agree that the data traffic - no matter how it is defined - will increase exponentially for several years as it has been doing the last decade. The disagreement concerns how fast and how large the ICT related power use will become in around 2030.”

We recently caught up with Andrae to hear more on his perspective of this issue. “If we try to get data that are not available we will spend 80 percent of the time chasing a ghost,” he says. “It’s better to measure what we can. We don’t know how much [IT] equipment is out there, and you cannot measure every data centre in the world.”

Instead, he suggests that the key might be to think about the future effects of enhanced performance of semiconductor chips. “The answer lies in the semiconductor roadmap,” he says. “Joules per computation, or the electrical intensity, is relevant to the processing for web browsing. If the number of computations per second grows slower, then that will flatten the curve for electricity use.”

However, there is a twist to this statement. The rise of artificial intelligence in business processes will likely increase the volume of computations borne through the internet. “Every business model will have to implement some form of AI in order to survive,” Andrae notes. “That will increase the number of global computations, and the joules per computation would have to be very small not to increase [the web’s overall energy use] by very much.”

With all these points considered, Andrae acknowledges that it is “frustratingly rough [to calculate] the internet’s kWh per gigabyte”. However, even if we do nothing, he suggests that electricity usage of the internet - and the accompanying emissions - will carry on rising.

This isn’t an entirely negative prediction, however. “Some people say we need ‘data sobriety’. But information technology is in everything, the digital is an enabler,” Andrae notes. “We have to use the internet in a positive way.”

Small differences, on a planet with finite resources, add up to something. So what, as individuals and businesses, can we do to reduce our footprint from web browsing? Our company, Neuto, a micro climate tech start-up based in Glasgow, Scotland, wants to start a conversation around web emissions - helping people and businesses to consider electricity and carbon burned from online activity just as readily as they’d measure their screen-time hours and minutes.

Our website offers a few ways to keep track of your web carbon footprint. Read more about our Neuto Carbon Monitor and our Neuto Browser Extension, plus don’t forget to sign up for our Neutoletter for more updates on the world of web carbon emissions.