What is net zero - and why are Tory leadership hopefuls criticising it?

As the hunt for a new prime minister gets underway, environmental charities and MPs have expressed concern that the new Tory leader could derail the UK’s net zero target.

Introduced last year ahead of COP26, the UK’s net zero strategy is one of the most significant pieces of climate change legislation overseen by Boris Johnson while he was PM.

With Johnson now exiting office in the autumn after resigning from his post, net zero ambitions could be under threat if not supported by a new PM.

Some Tory leadership candidates such as Kemi Badenoch have even come out in direct opposition to net zero plans, pledging to scale them back to reduce costs. 

Aside from leadership candidates, the Conservative Net Zero Scrutiny Group has also expressed scepticism about the 2050 target, claiming the costs are too high given the current economic climate.

If you’re still wondering exactly what net zero entails and why it’s so important, here’s everything you need to know about the target, and why it’s causing so much controversy.

What does net zero mean – and what is a net zero economy?

“Net zero” simply refers to a situation in which the amount of greenhouse gases being pumped into the atmosphere is equal to the amount being removed through other means such as tree-planting. 

It differs from total decarbonisation, which involves halting all greenhouse gases from being emitted. 

Instead, under the government’s plans to reach net zero by 2050, some industries such as aviation will continue emitting greenhouse gases. 

The idea is that residual emissions from these sectors will be removed through natural carbon capture methods such as tree-planting, or through industrial carbon capture technologies. 

A “net zero economy” is simply one that operates in line with the principles of net zero, as outlined above. 

Will achieving the target by 2050 stop climate change? 

To curb climate change, all countries around the world must reduce their greenhouse gas emissions rapidly.

Failing to do so will lead to rapid heating of the planet and likely ecological collapse.

Scientists and experts around the world have agreed that reaching net zero emission by 2050 is the best chance the planet has of tackling global warming before it’s too late. 

In a landmark 2021 report, the UN’s International Panel on Climate Change (IPCC) warned of a “code red” for humanity, saying that today’s global leaders are likely to be the last group of politicians with the ability to hit the net zero target.

Without action by those in power now, they warned, governments in place by the end of the decade will have run out of time to fix the crisis. 

Thanks to historical greenhouse gas emissions, scientists say that a lot of planetary warming is already “locked in” even if the world does manage to stay within the 1.5C limit agreed at the Conference of Parties (COP) in 2015. 

The IPCC have said this means some changes are already “irreversible”, with droughts, floods, heat waves and storms becoming more frequent.

However, the IPCC also said the 1.5C limit is humanity’s best chance to avoid the very worst effects of climate change. 

What is the net zero strategy and how will it be achieved?

Last October, the government outlined its strategy for achieving net zero emissions by 2050 in its Net Zero Strategy.

The document outlined the roadmap the government will take towards curbing emissions across all sectors of society, from aviation to housing. 

Some of the key policies outlined included a pledge to power the UK on green electricity by 2035 and a ban on the sale of new petrol and diesel vehicles by 2030. 

A pledge was made to make the UK a “world leader in zero emissions flight” through use of sustainable aviation fuel.

The Net Zero Strategy also outlined plans to aid the transition away from oil and gas through investment in hydrogen production.

To decarbonise housing, the government is offering grants of £5,000 to encourage homeowners to replace their gas boiler with more eco-friendly heat pumps.

Home heating accounts for almost a fifth of total UK emissions. 

A commitment to improving nature by planting 30,000 hectares of woodland per year is also included in the strategy.

Farmers, meanwhile, will be incentivised to practice low-carbon methods of farming to reduce emissions from agriculture.

The government has promised the green transition will create hundreds of thousands of new jobs in sectors like renewable energy. 

Why 2050 for net zero?

The goal of reaching net zero emissions is to prevent global temperatures from rising 1.5C above pre-industrial levels by the year 2100, which scientists say is key to minimising soaring temperatures, rising sea levels and extreme weather. The increase sits at around 1.1C so far.

But reaching the target by 2050 actually only means having a 50 per cent chance of keeping temperatures below the 1.5C limit, the Committee on Climate Change said. Experts and policymakers did not think it would be realistic to reach net zero before 2050 though some nations have set earlier targets, including Scotland (2045).

How much does net zero cost?

There is a lot of uncertainty around the journey to net zero, so calculating exact figures is difficult for experts. But in 2019 the Climate Change Committee (CCC) estimated the total costs would be £50 billion per year, which is less than one per cent of GDP, while the Treasury said it could be closer to £70 billion per year.

Action taken to save the planet will save the government money, too. Better air quality and less reliance on cars will improve UK health. This could ease pressure on the NHS, which the CCC said could “partially or fully offset costs”.

Why are Tory leadership candidates rejecting the policy?

Some candidates in the Tory leadership race have failed to express ambitions around tackling climate change, while others have rejected net zero altogether. 

Kemi Badenoch, for example, said in an interview with the Telegraph that she was “not someone who doesn’t believe in climate change”, but added that it was “wrong of us to set a target without having a clear plan of the cost and knowing what it would entail”.

Senior Tory MP Steve Baker, who founded the Conservative Net Zero Scrutiny Group, has suggested that he will push for the next PM to scale back net zero ambitions. 

The most common argument against achieving the target by 2050 is that the costs will be too high. 

Scientists, including those on the CCC, however, have repeatedly outlined the fact that the costs of not acting on climate change will be far higher than the costs of implementing net zero.

What is the Net Zero Scrutiny Group?

With around 19 members in the House of Commons, the Conservative Net Zero Scrutiny Group (NZSG) has been set up to “scrutinise” the government’s key climate target.

Members of the group claim that a too-speedy transition to renewable energy has driven the current energy crisis, and say the cost of implementing net zero policies will be too costly, making the poorest poorer. 

They have called for cuts to green taxes and an increase in fossil fuel production – in spite of warnings from scientists that fossil fuel exploration should be halted.

The group say they are not climate change deniers, though two leading members have links to an organisation founded by long-term climate denier Nigel Lawson.

The group’s chair, the MP Craig Mackinlay, has also been accused of propagating misleading information by a leading climate institute.