Sodium-ion vs lithium-ion BESS: Cost parity not before 2031

pv magazine Italia spoke with Dario Bertagna, senior managing director and co-head of Clean Energy at Capital Dynamics, following his recent commentary in which he questioned whether Europe is replacing one energy dependence with another. Bertagna calls for a “Western” supply chain for panels, inverters, and especially battery energy storage systems (BESS).

The private asset management company, based in Zug, Switzerland, confirms its focus on Germany, Ireland, Italy, the United Kingdom, and Spain, arguing that an alliance between Brussels and Washington on batteries could come to fruition. “Europe and the United States, although experiencing a phase characterized by some tensions, could certainly collaborate on the topic of implementation and research” of sodium batteries, says Bertagna.

pv magazine: Europe is replacing one energy dependence with another, according to a recent position paper of yours. Could you explain why this is relevant for the photovoltaic world? Does this reasoning also make sense for panel production?

Dario Bertagna: The topic plays a central role for photovoltaics as well. If, as expected, the percentage of energy produced by solar power in Europe is destined to grow, strengthening storage capacity to manage production peaks and ensure grid stability will be critical. The risk is indeed that Europe manages, albeit through continuous investments and with a long-term horizon, to achieve greater independence in renewable energy generation, but remains dependent on non-European supply chains for batteries. The same reasoning applies to panels: European dependence on the Asian supply chain in solar is already well known and represents a precedent very similar to what today risks happening in storage.

You report that Europe could invest €80 billion in BESS. What would be the corresponding European capacity?

The reference, in this case, is to the forecast according to which European BESS capacity could exceed 50 GW by 2030, with an investment requirement in the range of €80 billion.

In which countries do you think it makes the most sense to invest in BESS solutions at the moment?

Every market is unique and presents its own complexities, ranging from regulatory aspects to urban planning. However, we continue to see opportunities in the main markets where we operate: the United Kingdom, Italy, Spain, Ireland, and Germany.

You wrote that sodium-ion batteries have recently reached a turning point. However, the technology is not yet considered mainstream, despite having attracted investor attention. What is missing? Who should invest now? A public-private partnership?

We expect lithium-ion battery technology to remain dominant throughout the next decade. However, the profitability of sodium-ion technology continues to improve and, very importantly, this element offers investors greater flexibility. With the progressive refinement of manufacturing processes, battery operational range, and energy density, it is likely that sodium-ion technology will find increasingly widespread use in energy storage projects.

You write that the main current limitation remains cost. “In 2025, the average cost of sodium batteries stood at $59 per kWh, compared to $52 per kWh for LFPs, with a 13% differential that is significant at the utility scale. However, achieving cost parity with LFP technology is expected to take a few years,” you recently reported. How many years?

The speed with which this goal will be achieved will largely depend on the volume of investments, demand, manufacturing capacity, and, obviously, the political choices carried out in this sector. It is difficult to imagine, considering the current scenario, that this could happen before the next five years [before 2031].

You write that the model already observed in the early stages of the lithium-ion battery market risks being replicated for sodium batteries as well, unless European and American manufacturers act promptly, supported by adequate public policies. In your opinion, is there room for collaboration between Brussels and Washington in this field? Despite the tensions?

The security of energy supply chains is a common strategic interest. Europe and the United States, although experiencing a phase characterized by some tensions largely due to the evolution of the international macroeconomic scenario and certain economic policy choices (for example, tariffs), could certainly collaborate on the implementation and research of this technology.

In conclusion, what is the timeline for hitting the strategic goal of building a storage industry and a broader grid infrastructure under the control of Western countries?

In this case too, it is very complex to make forecasts. However, it is evident that this is not a goal that can be achieved in a few years, but this decade is the decisive one. Europe needs massive investments in energy storage to achieve true independence. This requirement cannot be met by a single technology, let alone by depending on a single geographic area. The goal is therefore to build a storage industry and a broader grid infrastructure under the control of Western countries. A strategic and ambitious goal that will take time.

From pv magazine Italy.