We must reduce global energy consumption to reach net zero emissions by 2050

Many climate activists, scientists, engineers and politicians are trying to reassure us the climate crisis can be solved rapidly without any changes to lifestyle, society or the economy.

To make the vast scale of change palatable, advocates suggest that all we have to do is switch fossil fuels for renewable power, electric vehicles and energy efficiency technologies, add seaweed to livestock feed to cut methane and embrace green hydrogen for heavy industries such as steel-making.

There’s just one problem: time. We’re on a very tight timeline to halve emissions within eight years and hit net zero by 2050. While renewables are making major inroads, the world’s overall primary energy use keeps rising. That means renewables are chasing a retreating target.

My new research shows if the world’s energy consumption grows at the pre-COVID rate, technological change alone will not be enough to halve global CO₂ emissions by 2030. We will have to cut energy consumption 50-75% by 2050 while accelerating the renewable build. And that means lifestyle change driven by social policies.

The limitations of technological change

We must confront a hard fact: In the year 2000, fossil fuels supplied 80% of the world’s total primary energy consumption. In 2019, they provided 81%.

How is that possible, you ask, given the soaring growth rate of renewable electricity over that time period? Because world energy consumption has been growing rapidly, apart from a temporary pause in 2020. So far, most of the growth has been supplied by fossil fuels, especially for transportation and non-electrical heating. The 135% growth in renewable electricity over that time frame seems huge, but it started from a small base. That’s why it couldn’t catch fossil fuelled electricity’s smaller percentage increase from a large base.

As a renewable energy researcher, I have no doubt technological change is at the point where we can now affordably deploy it to get to net zero. But, if energy consumption continues to grow, the transition is not going to be fast enough on its own, even after taking account of improvements in energy efficiency. If we don’t hit our climate goals, it’s likely our planet will cross a climate tipping point and begin an irreversible descent into more heatwaves, droughts, floods and sea-level rise.

Our to-do list for a liveable climate is simple: convert essentially all transportation and combustion heating to electricity while switching all electricity production to renewables. But to complete this within three decades is not simple. Even at much higher rates of renewable growth, we will not be able to replace all fossil fuels by 2050.

This is not the fault of renewable energy. Other low-carbon energy sources like nuclear would take much longer to build and leave us even further behind growing consumption.

Do we have other tools we can use to buy time? CO₂ capture is getting a great deal of attention, but it seems unlikely to make a significant contribution. The scenarios I explored in my research assume removing CO₂ from the atmosphere by carbon capture and storage or direct air capture does not occur on a large scale, because these technologies are speculative, risky and very expensive.

The only scenarios in which we succeed in replacing fossil fuels in time require something quite different. We can keep global warming under 2℃ if we slash global energy consumption by 50% to 75% by 2050 as well as greatly accelerating the transition to 100% renewables.

Individual behaviour change is useful, but insufficient

Let’s be clear: individual behaviour change has some potential for mitigation, but it’s limited. The International Energy Agency recognises net zero by 2050 will require behavioural changes as well as technological changes. But the examples it gives are modest, such as washing clothes in cold water, drying them on clotheslines, and reducing speed limits on roads.

The 2022 Intergovernmental Panel on Climate Change report on climate mitigation has taken a step further, acknowledging the importance of collectively reducing energy consumption with a chapter on “Demand, services and social aspects of mitigation”. To do this effectively, government policies are needed.

Rich people and rich countries are responsible for far and away the most greenhouse gas emissions. It follows that we must reduce consumption in high-income countries while improving human well-being.

We’ll need policies leading to large scale consumption changes

We all know the technologies in our climate change toolbox to tackle climate change: renewables, energy efficiency, electrification, green hydrogen. But while these will help drive a rapid transition to clean energy, only energy efficiency is designed to cut consumption and its potential is limited, although significant.

The following policies would cut consumption further:

• a carbon price and additional environmental taxes

• laws to encourage design of products for reuse, recycling and remanufacture

• wealth and inheritance taxes to reduce consumption by the rich

• non-coercive policies to end population growth, especially in high-income, high-consumption countries.

Why would the vast majority of people support these policies? Because they would receive benefits in the form of:

• a substantial increase in government spending on poverty reduction, green infrastructure, health-care, public education and public transport as part of a shift to Universal Basic Services​

• a shorter working week to share the work around

• a job guarantee at the basic wage for all adults who want to work and who can’t find a job in the formal economy

• a substantial increase in pensions.

Funding the transition

The federal government funded the economic response to the pandemic by borrowing hundreds of billions of dollars via Quantitative Easing (QE). This is not responsible for the inflation we are currently experiencing, namely cost-push inflation. This is driven mainly by a shortage of raw materials during pandemic recovery, leading to increases in costs and hence prices. According to the Reserve Bank, in Australia in the December quarter “price increases for newly constructed dwellings, consumer durables and automotive fuel, which together comprise around one-third of the CPI [Consumer Price Index] basket, accounted for around two-thirds of the increase in the headline CPI in the quarter”.

As I understand it, the type of inflation arising when the governments and/or the private sector spends very large amounts of money, is known as demand-pull inflation. If the resulting increased demand exceeds supply, prices will likely rise. The key to avoiding or minimising demand-pull inflation is to limit spending to within the productive capacity of the national economy. This can be assisted by using part of the spending to increase the nation’s productive capacity by, for example, funding education and training, incentivising new (clean) industries and building essential infrastructure. Then there is low risk of driving inflation.

As an alternative to QE, a federal government guided by Modern Monetary Theory could simply create the funds in its own currency instead of borrowing them. Spending this created money has no more risk of demand-pull inflation than spending money borrowed via QE, because demand-pull inflation arises from the spending of money, not its source (provided it’s not overseas currency).

Change is happening

We can cut consumption and emissions, while improving the quality of life for the vast majority of the population. However, these policies mean major change. But, like it or not, major disruptive change in the form of climate change is happening regardless. Let’s try to shape our civilisation to be resilient in the face of change.

illuminem Voices is a democratic space presenting the thoughts and opinions of leading Energy & Sustainability writers, their opinions do not necessarily represent those of illuminem.