Researchers investigated which solar module stockpiling conditions could help to ensure stable solar PV deployment at the lowest cost in Europe. The scientists demonstrated that stockpiling is cost-effective primarily under unfavorable import conditions.
A group of researchers from the Technische Universität Wien in Austria and the Norwegian University of Science and Technology have conducted a techno-economic analysis to understand what level of solar modules stockpiling could be used for the European Union to achieve stable solar PV deployment at the lowest cost possible.
The scientists explained that compared to traditional energy carriers, such as oil and gas, stockpiling photovoltaic modules suffers from relatively fast technological obsolescence. They also noted that the global solar module market is currently characterized by high concentration in China and oversupply, with the EU being heavily reliant on imports and eventually unable to reach the 40% solar manufacturing benchmark set by the EU Net-Zero Industry Act (NZIA) by 2030.
The research team investigated, in particular, the optimal levels of strategic solar module stockpiles in the EU by 2050 and the impact of the European initiatives to re-create a domestic solar manufacturing ecosystem.
“Consistent with conventional energy system optimization modeling approaches, our analysis optimizes electricity supply to meet demand while minimizing total system costs,” it further explained, noting that their approach was mostly intended to investigate how different energy scenarios influence the optimal stockpiling levels rather than cost-optimal levels.
“The model’s key decisions include determining the optimal capacity and utilization of various energy generation technologies, such as hydro, wind, and biomass, alongside the stockpiling levels of solar modules in response to evolving short- and long-term energy system developments,” it added.
The academics identified 36 future energy scenarios with different levels of EU solar manufacturing, energy costs, carbon prices, commodity prices, import dynamics, shares of renewables penetration, technology advancements, and fossil phase-out roadmaps, among other factors. They also predicted that the cumulative PV capacity in the EU may range from 1,076 GW and 1,784 GW in 2040 and from 1,526 GW to 2,252 GW in 2050.
Their analysis showed that high levels of solar module stockpiling would not be likely in 28 of the proposed scenarios, as the economic driver for their creation is insufficient.
As for the other 8 scenarios, researchers found they are characterized by high import costs, an import stop, or tight solar market conditions, as well as by the achievement of the above-mentioned 40% benchmark set by the EU for domestic manufacturing. “During the 2030s, average stockpile levels range from 164 to 180 GW, which is around 300% of annual additions,” they emphasized. “In earlier and later periods, levels are notably lower, averaging between 27 and 33 GW, which is around 50% of annual additions.”
The academics also noted that the 8 scenarios favorable to stockpiling also see import dependency being reduced, as the stockpiling system itself ensures the necessary temporal flexibility between injection and withdrawal, which they say is very similar to a diversification strategy. “Interestingly, the strategic reserve of solar modules exerts a stabilizing effect on optimal wind and solar capacities, highlighting its broader role within the energy system,” they concluded.
The research work was presented in the study “Strategic solar module stockpiling in the EU: A scenario-based analysis of costs and benefits beyond 2030,” published in Energy Policy.
