New research claims that the world may have crossed a “tipping point” that will make solar power our main source of energy by 2050. 

The research, led by teams at the University of Exeter and University College London (UCL), was based on a data-driven model of technology and economics that showed how solar photovoltaics (PV) will likely become our main source of power by the middle of the century, even without support from other climate policies. 

And yet there are still significant “barriers” that could hinder this outcome. This includes the need for stable power grids, proper financing for solar within developing economies, capacity of supply, and resistance from those whose jobs rely on traditional energy industries. 

“The recent progress of renewables means that fossil fuel-dominated projections are no longer realistic,” Dr Femke Nijsse, from Exeter’s Global Systems Institute, said in a statement.

“In other words, we have avoided the ‘business as usual’ scenario for the power sector. However, older projections often rely on models that see innovation as something happening outside of the economy. In reality, there is a virtuous cycle between technologies being deployed and companies learning to do so more cheaply. When you include this cycle in projections, you can represent the rapid growth of solar in the past decade and into the future.”

In addition, traditional models have tended to assume there is a point where we stop “learning” about a technology in the future, but this is not the case. In fact, we are still seeing new and rapidly developing innovations in solar technologies. 

“Using three models that track positive feedbacks, we project that solar PV will dominate the global energy mix by the middle of this century,” Nijsse added.

However, the team warns that solar-dominated electricity systems could become “locked into configurations that are neither resilient nor sustainable, with a reliance on fossil fuel for dispatchable power.”

They advise that, rather than trying to implement the solar transition in itself, governments should focus on overcoming the four specific barriers mentioned above. 

The first of these is “grid resilience”, which refers to the fact that solar generation varies at different times and under different conditions (day/night, season, weather). As such, grids need to be designed with this in mind. 

Nijsse said: “If you don’t put the processes in place to deal with that variability, you could end up having to compensate by burning fossil fuels.”

Ways to improve resilience include building and investing in other renewable sources, such as wind, as well as using transmission cables to connect different regions, establishing extensive electricity storage options and providing policies that manage demand – this could include incentives to charge electric cars at non-peak times. 

Importantly, government funding of R&D can make a huge difference at the early stages of creating a resilient grid.

Then there is access to sufficient finances. Solar growth requires the availability of funds to sustain it. At the moment, low-carbon finance is extremely concentrated in high-income countries while lower-income countries miss out. Even international funding initiatives tend to favor middle-income countries, which leaves countries in Africa and elsewhere with less financial support despite its huge potential. 

In addition, there is a need to provide the needed materials for the supply chain. A solar-dominated future will likely be metal- and mineral-intensive, which will increase the demand for “critical minerals”. Electrification and batteries need large-scale raw materials, such as lithium and copper. As efforts to decarbonize our energy sources continue, renewable technologies are expected to make up 40 percent of total mineral demand for copper and rare earth elements, as well as 60 and 70 percent for nickel and cobalt, and around 90 percent for lithium by 2040. 

Finally, political resistance from existing and traditional industries may slow this crucial transition. A rapid transformation in how we get our energy may impact the livelihoods of up to 13 million people across the world who work in the fossil fuel sector and other dependent industries. 

There will be a greater need for adequate regional economic and industrial development policies to help resolve inequity and to mitigate the political pressures from declining industries. 

“There is a growing belief that, with the dramatic decline in the global average cost of renewables, it will be much easier for the developing world to decarbonise,” Dr Nadia Ameli, from UCL’s Institute for Sustainable Resources, explained. 

“Our study reveals persistent hurdles, especially considering the challenges these nations face in accessing capital under equitable conditions. Appropriate finance remains imperative to expedite the global decarbonisation agenda.”

The study is published in Nature Communications.