Is software part of the climate problem?
Software is not clean or "green" by default. It has an impact on the world around us. It has a carbon footprint. It uses a lot of energy. It creates waste. Demand for internet services continues to increase. In this post, we will consider to what extent software is part of the environmental problem. Of course, software is also part of the solution to becoming more sustainable, which we will explore in a later post.
As software professionals, we often contrast "digital" with slower analogue and paper processes. Digital has transformed the way we access information. Viewing your bank account, browsing for houses or renewing your passport can be done without leaving your sofa. So yes, that saves a lot of paper and wastage. But digital relies on the internet which means it is physical.
When we talk about "green software" we are thinking about software systems. Software systems include devices, networking, data centres and software that runs across all of these. And so, the impact we are examining is from Information Technology generally.
It's worth noting that all the data referenced is an estimate. It is not possible to measure ICT usage nationally or globally. But these are the best estimates we can find, and they come from multiple sources.
Software has a carbon footprint
“IT produced 1.8-2.8% of greenhouse gas emissions (GHG) in 2020”.
The Paris Agreement set most countries on a course to reduce Greenhouse Gas emissions by 2050. The goal is to limit the temperature increase to +1.5c of pre-industrial levels. The UK has committed, in law, to reduce its GHG emissions by 78% nationally by 2035 (compared to 1990 levels) on its way to net zero.
It may seem like IT is only a minor contributor compared to other industries. In fact, it's similar to the entire aviation industry. The reality is that every industry must contribute to the reduction or GHG emissions will continue to increase. And it's worth noting that most industries are dwarfed by the energy industry which brings us nicely to the electricity consumption of IT.
Software has a thirst for electricity
“The internet is the greatest, most energy intense, machine that has ever existed”.
When we think about IT as a globally connected machine instead of just a large collection of devices, servers and software it allows us to think about it collectively. Globally, the internet consumed 4-6% of all electricity generated in 2020, so becoming more energy efficient should be a priority for software and hardware designers.
Ireland is home to many data centres, both from the hyper-scale public clouds and private clouds. It's estimated that by 2031 data centres will account for 28% of Irish energy consumption. The energy efficiency of data centres and software deployed will become increasingly important. Better software design can reduce carbon intensity by using energy sources more intelligently. Through improved design we can reduce both emissions and cost.
Renewable energy has risen dramatically over the past decade. In the EU, renewable energy now accounts for more than 20% of the total electricity supply. This allows us to consider how "green" the electricity supply is. The hyper-scale cloud providers are helping by investing in renewables for their data centres. But even if 100% of our electricity supply is from renewables, it will still be important to prioritise energy efficiency for the internet, as electricity is a scarce resource.
Software can't rely on hardware efficiency
“Software efficiency halves every 18 months, compensating "Moore’s Law”.
In 2023 there are 5.1 billion internet users worldwide, which is 64% of the global population. Given the appetite for more internet services it seems clear that demand will increase. However, there is debate among experts whether the internet will increase or reduce its carbon footprint given the increasing efficiency of hardware.
Moore's Law describes the doubling of efficiency of hardware every two years. But Moore's Law is slowing as microchips shrink towards 1nm. And so, the processing efficiencies we have seen over the past decades could also slow. Meanwhile software is said to become less efficient over time, the inverse of hardware. This scenario means without a major change in software design to prioritise sustainability, the carbon footprint of the internet will increase.
Software creates digital waste
“68% of data available to businesses is never used”.
The Economist said that data was now more valuable than oil. And so data became the new oil. This now has a double-meaning. The collection and storage of data is growing dramatically year-on-year. It may be relatively cheap to store all this data in the cloud but there is a growing energy and carbon footprint. And if this data is not valuable, if 68% of it is never used, then this data amounts to a growing pile of waste.
Reducing digital waste must be a priority for software design along with energy efficiency, carbon efficiency and carbon intensity. Software vendors have a duty to ensure their software purges unused data and continues to support older devices to reduce device waste and early replacement.
The need for Green Software
We have seen that software needs to be greener. Together with the cloud and hardware computing all three can play a part in ensuring a more sustainable future. This is why Kainos, as a responsible business, sees the need to play its part. We can help to make the software systems we develop for our customers greener. If you would like to discuss how your software services can be greener, please get in touch with us.
The next post in this Green Software series will examine how software can be part of the solution.