The government has set a formal target to hit net zero in the UK by 2050. But what exactly does that mean?
Net zero is when the greenhouse gases we emit are reduced to the point where they can be balanced out by the greenhouse gases we remove from the atmosphere. In other words, it means no negative impact on the climate overall.
Climate scientists like to use the metaphor of a bath – if you pour in water faster than it empties through the plughole, the bath will fill up and eventually overflow. But if you balance the amount you put in with the amount draining away, by slowing down the tap and/or increasing the size of the plughole, then the water in the bath will remain level.
Net zero is also often known as ‘carbon neutral’, because greenhouse gas emissions are generally measured in CO2 (the most prominent greenhouse gas). You may even have come across the term ‘carbon negative’, which takes things one step further by removing more greenhouse gases from the atmosphere than you put in, resulting in a net positive impact on the environment. Some leading companies such as Microsoft are already moving in this direction.
But let’s not get ahead of ourselves – we’ll start with net zero.
In 2015, world leaders came together in Paris for a UN summit on climate change, formally known as a COP. Paris was COP21, and it resulted in an historic global climate agreement.
Nearly 200 countries agreed to take action to reduce their emissions in a bid to limit global warming to 1.5°C above pre-industrial levels. Climate scientists say the global community needs to reach net zero by the middle of the century at the latest for a reasonable chance of achieving this.
This is no mean feat. Global temperatures have already risen by 1°C, and we’re on course for 3-5°C unless more action is taken. Donald Trump infamously pulled the US out of the Paris Agreement when he became President, but Joe Biden has already committed to reinstating the US when he comes to power.
The UK became the first major country to set a net zero target of 2050 in 2019. Achieving this will require a complete transformation in almost all aspects of society. We will need to reduce emissions to as close to zero as possible by being far more efficient and intelligent in how we generate and use energy, how we consume materials and other resources, how we transport ourselves and our goods, and how we manage our waste.
We will also need to increase the amount of CO2 we remove from the atmosphere by changing the way we use land – for example by planting trees and restoring nature – and by developing new technologies that capture and store carbon from the air.
Much of this will be driven by national policy. The forthcoming ban on the sale of petrol and diesel vehicles is just one example of the sort of major government intervention we can expect over the coming years.
Ultimately, achieving much of what is required for net zero will fall on the shoulders of businesses. Urged on by consumers, shareholders, climate-related legislation and the risks of climate change itself, many of the world’s largest companies have already drawn up their own net zero plans. Often, these include targets far in advance of 2050.
The number of corporate net zero commitments have tripled over the last year, in what has been coined the ‘Race to Zero’. At the time of writing, 1,541 companies with a combined revenue of over £8.5 trillion have formal net zero targets in place.
These net zero commitments will have a profound impact on supply chains. A 2018 survey by HSBC found that nearly a third of companies around the world planned to make their suppliers more sustainable in the immediate future. In 2020, the number of large-scale buyers asking suppliers for environmental data increased by 24 per cent.