Climate change is hot on the agenda.
UK local authorities are declaring climate emergencies as a result – the target: to reach net zero emissions before 2050.
Public understanding of net zero, though, is varied, with confusion between ‘actual zero’ and ‘net zero’ (often used publicly as synonyms), and the hidden impacts of ‘offsetting’ out of sight and out of mind.
Here, Jacob Roberts, Infrastructure Strategy Specialist at Cenex, looks at the meaning of ‘net zero’ and the low emission solutions available to achieve it.
What is net zero?
Net zero = total carbon emissions – total carbon offsetting = 0gCO2.
The UK Government describes net zero as meaning “that the UK’s total greenhouse gas emissions would be equal to or less than the emissions the UK removed from the environment”.
While “zero emissions” implies that no fossil fuels will be burnt and no emissions released, net zero acknowledges that some carbon emissions are unavoidable, but instead can be offset by, for example, capturing and storing CO2 or by planting trees.
So if you emit 100 tonnes of carbon a year and you offset 100 tonnes of carbon a year you’re at net zero.
It’s like a bank balance – when your incomings are the same as your out-goings then your balance is zero, but that’s not saying you didn’t spend or earn anything.
The whole idea of thinking of carbon as a budget or balance is fairly common and the UK Government has set “carbon budgets” since 2009 that impose legal limits on the amount of carbon that the UK can emit.
We are currently in the UK’s third carbon budget, which prevents the UK from releasing any more than 2,540 million tonnes of carbon emissions between 2018 and 2022.
To put that in perspective, you would have to drive a car over a lightyear to emit that much carbon!
Even though the UK is on track to be well within the target set in the third carbon budget, we still have a long way to go to become net zero by 2050!
Why is net zero important?
We need to reduce our emissions and prevent catastrophic climate change.
This is not a coincidence and it is forming part of a worrying trend, but it’s not too late to turn things around by reducing and offsetting emissions and reaching net zero.
The concept of net zero is important because, even though we need to reduce emissions, it’s not feasible to completely live without them, with certain industries unlikely to ever be completely zero emission.
By setting targets based on net zero, we are encouraging research and development into carbon offsetting that will enable us to continue to use fossil fuels where there is no feasible alternative.
That being said, we should not use net zero as an excuse to justify continued reliance of fossil fuels.
Offsetting should ideally only be used to address areas where we have no other option.
How does transport reach net zero?
Many areas of society could feasibly become zero emission – anything powered by electricity can be made zero emission by using renewable energy – but transport as a sector is more tricky.
For light vehicles, it’s fairly clear cut: for small vans and cars there’s a good proportion of owners who could transition to an electric alternative without any inconvenience.
Electric vehicles produce zero tailpipe emissions and release less CO2 than petrol or diesel, even when they are charged with electricity generated using fossil fuels, which is reducing all the time as the UK keeps breaking records for the amount of renewable energy on the grid.
Alternatively hydrogen fuel cell electric vehicles also produce zero tailpipe emissions and can be truly zero-emission with hydrogen generated using renewable energy, and biomethane from sustainably sourced crops can also reduce emissions as any emissions released are absorbed in the growing of the crops.
In terms of public transport, trains have long been the lowest carbon mode of travel, taking advantage of efficient and potentially zero carbon renewable energy, and the move to very light rail is an important part of achieving net zero emissions.
However, long-distance and international transportation – particularly aviation and shipping – will probably always be somewhat dependent on fossil fuels and therefore continue to release carbon emissions so those are the areas we will really need to think about carbon offsetting.
How does transport support the wider transition to net zero?
A lot of research and development is being undertaken to explore how zero-emission vehicles, particularly electric vehicles, can be used to support the wider transition to net zero.
Smart charging technology can allow an electric vehicle to charge when renewable energy generation is at its highest or prevent charging when there is high-demand on the grid, to save money and reduce emissions.
Vehicle-to-Grid (V2G) takes this a step further and allows an electric vehicle to use electricity from their vehicle battery back to power their homes, or to support the grid.
This means renewable electricity can be used to charge an EV battery with V2G when its cheap and then discharge it back when grid electricity is expensive and carbon intense.
It can also allow an electric vehicle to support the grid during periods of high demand, effectively doing a job that is currently often done by diesel generators, but with lower or potentially zero emissions.
Having that ability to take energy at one time and use it at another time can help households to save money on their electricity bills, but it is also really important for reducing carbon emissions.
What can I do to lower my transport emissions?
The most important thing is travelling less.
If you do need to travel, use the most low carbon transport method possible – ideally walk or cycle, then look to use public transport or car share, or, if you have to, drive yourself.
If you have to drive, ideally use a low or zero emission vehicle but, whatever you are driving, drive it as efficiently as possible: take the most efficient route while avoiding congestion, try not to accelerate or brake more sharply than you need to.
It’s important to remember that the biggest impacts are not achieved when a few people make huge changes to their lives, but when we all make small changes.
As an independent not-for-profit, Cenex works with your business or organisation to find a viable and sustainable solution that achieves the greatest carbon reduction within a reasonable budget and timeframe.
Together, we can lower your emissions through innovation in transport and energy infrastructure.