In the terminology of the climate and ecological crises the phrase “tipping point” is loaded with dreadful implications.
It evokes a climate breakdown supercharged by the mass escape of methane locked in Siberian permafrost, or the great currents of the oceans smothered by freshwater melting from the Greenland ice sheet, or the Amazon turning from great rainforest to parched savannah after the felling of one too many trees.
But it could come to mean something very different.
Policymakers could tip the world into a series of “positive tipping points”, accelerating the switch from fossil fuels to clean energy sources, by simply introducing mandates requiring key sectors to make the change, a report claims.
The researchers say such “regulatory mandates with specific timeframes” could stipulate that certain industries make a rising share of sales of clean technologies or phase out the most polluting fuels.
Once reached, these tipping points could trigger benevolent cascades in related sectors, with each accelerating the others down the path of a low-carbon transition, while simultaneously slashing prices for consumers.
It is an idea with urgency behind it. Experts say global CO2 emissions must be halved by 2030 if the world is to have any hope of limiting the global temperature rise to 1.5C, beyond which devastating impacts are expected. Meanwhile emissions are still rising.
Prof Tim Lenton from the Global Systems Institute (GSI) at the University of Exeter, which is behind the research, said: “With the world off course to meet the Paris agreement climate goals, triggering positive tipping points is now the only credible way to limit global warming well below 2C (3.7F) above preindustrial levels.
“We need a rapid transformation in our economies and society that dramatically cuts prices and carbon emissions. Focusing on positive tipping points benefits consumers, taxpayers, businesses and people around the world facing the worst impacts of climate change.”
What the latest research shows is that, of all the possible government interventions, mandates are the most effective way to push industries towards such tipping points.
Using data from more than 70 countries, including all the big carbon emitters, GSI’s researchers used modelling to predict the impact of different kinds of government interventions – taxation, subsidies and regulatory mandates – in encouraging decarbonisation in energy generation, heating, and light and heavy road transport.
The modelling simulated how investors or consumers choose between technologies based on availability, cost and historical preferences.
The study found taxation – hitherto the most commonly used policy – to be the weakest intervention, while regulatory mandates had the biggest impact, quickly leading adoption of clean technologies to levels that triggered positive tipping points in related industries.
Four such mandates were assessed and are recommended by the report, including: phasing out coal power by 2035 for developed countries and by 2045 for developing countries; requiring a rising proportion of heating appliance sales to be heat pumps from 2025, reaching 100% by 2035; requiring a rising proportion of car sales to be zero-emission vehicles, reaching 100% by 2035; and requiring a rising proportion of truck sales to be zero-emission vehicles, reaching 100% by 2040.
“We found that policies to advance the low-carbon transition in any one of these sectors will help bring forward the tipping point in the other three,” said Simon Sharpe, a co-author of the study and the director of S-Curve Economics, a nonprofit research organisation.
“For example, increased use of clean electricity or energy storage in one sector drives innovation and brings down the cost of these technologies, enabling faster transitions in the other sectors. In addition, the increasing electrification of heating and transport provides new options for balancing the power system, reducing the cost of clean power.”
The paper also identifies “super-leverage points” with the greatest potential to trigger cascades of positive change. Dr Femke Nijsse, the lead author of the study, said: “The zero-emission mandate for cars shows the best potential for a ‘super-leverage point’ for the global transition.
“This policy not only has the highest effect within its own sector, but also has a significant positive influence on the transition in other sectors. Coal power phase-out is also a super-leverage point, bringing forward positive tipping points in the heating and heavy road transport sectors by up to four years in some countries.”
The UK is preparing to close its last coal-fired power station, at Ratcliffe-on-Soar in Nottinghamshire, at the end of this month, which will make it the first G7 country to phase out coal power.
Lenton said: “Mandates are clearly the most effective policy approach – and we call on policymakers worldwide to implement them at speed. Failure to do so will have high human and economic costs.”
