Solar power (also known as photovoltaics, or PV) is likely to become the dominant power source worldwide by 2050, according to a new study. The analysis suggests the shift is likely to occur even without additional climate policies – although at least four barriers remain that could derail solar’s ascent and lock in continued fossil fuel use.
“Historical policy to stimulate solar PV has brought down costs. We’re now at the point that a virtuous cycle between cost declines and additional deployment doesn’t require more ambitious policies targeting solar anymore,” says study team member Femke Nijsse, a climate and energy systems researcher at the University of Exeter in the UK. “More ambitious policies for other renewables [are] still needed.”
Over the last decade and a half, the cost of solar panels and wind power have plummeted. Researchers had begun to talk about a ‘tipping point’ where renewables might outcompete fossil fuel sources of energy based on cost alone, but there was little agreement on when or how this might occur.
As a result, models of the global energy system have generally assumed that fossil fuel dominance would continue. Past models have also consistently underestimated how fast solar power would grow in the real world.
Instead, Nijsse and her colleagues analyzed the global energy system using a set of three models that incorporate that virtuous cycle between expansion of green technologies and falling costs. The models use real-world technological and economic data to forecast the rollout of various energy technologies through the year 2060.
Solar power is likely to outpace wind starting around 2030, and become the dominant energy technology worldwide by 2050, the researchers report in the journal Nature Communications.
The findings echo those of a study last year that suggested a rapid transition to renewable sources of energy will be massively cheaper than continuing to rely on fossil fuels. The new study suggests it no longer makes sense to consider the continued dominance of fossil fuels a “business as usual” scenario.
The result was unexpected, Nijsse says: “We were seeking to find which policy was required to ‘tip’ this tipping point. We found it had already tipped, assuming a set of four barriers can be overcome or avoided.”
The four barriers to solar’s takeover are unstable power grids, lack of financing for solar in developing countries, supply chain capacity, and political resistance from regions that lose jobs. Policies that address these barriers may be more effective in bringing about the clean energy transition than efforts to bring down the price of solar such as by carbon taxes, the researchers say:
1. To achieve resilient electric grids that can accommodate daily, seasonal, and weather-related variations in the amount of solar available, policymakers can add other renewables, power transmission links between regions, batteries and other forms of energy storage, and policies to manage demand for power. Otherwise, the world could get locked into an energy system that relies on fossil fuels to meet peaks in energy demand.
2. New policies are also needed to extend financing for solar deployment to developing countries. Currently, solar finance is concentrated in high-income countries, and even international development aid for this purpose is concentrated in middle-income countries. Low-income countries especially in Africa are left out. As a result, it’s not certain that falling costs alone will enable the developing world to decarbonize.
3. Electrification and batteries require large amounts of certain minerals and metals, like copper, nickel, cobalt, lithium, and rare earth elements, and the supply chains for these are sometimes weak. Research is needed to find alternatives, and policies to maximize recycling and reuse of materials will also be important.
4. Finally, political opposition from fossil fuel interests and communities that depend on fossil fuel employment could put a damper on solar deployment. Making sure fossil fuel-dependent communities are taken care of in the green transition could help prevent some of this pushback.
Nijsse and her collaborators are now on the hunt for tipping points elsewhere in the global energy system, especially related to home heating and electric vehicles. “What we want to study in much more detail is the interactions between sectors, and how that impacts the first barrier we identify (grid stability),” she says. “Can we use surplus solar energy to pre-heat hot water or houses? Can we use EV car batteries for grid storage? If so, can we create cascades of tipping points?”
Source: Nijsse F.J.M.M. et al. “The momentum of the solar energy transition.” Nature Communications 2023.
Image: ©Anthropocene Magazine.