As Greece accelerates its push toward subsidizing energy storage systems, a fundamental question has yet to be addressed: Has there been any independent, science-based study that forecasts where the cost of storing energy—measured as the Levelized Cost of Storage (LCOS)—will stand five years from now?
This isn't a technicality. Without robust projections based on credible analysis, government subsidies risk becoming a new burden on taxpayers—repeating the same costly errors made during earlier renewable energy rollouts.
In past decades, generous subsidies for solar and wind were introduced without a long-term financial plan. Today, Greek consumers are still paying the price. While the market rate for electricity is around €50 per megawatt-hour, subsidized energy through legacy mechanisms costs over €120, a gap covered through additional charges on consumer bills. The public was promised that renewables would drive down prices. Instead, they're paying more than twice the going rate.
What makes the current situation more precarious is the pace of technological change. The cost of batteries—particularly lithium-ion—has been falling rapidly, and the storage technologies considered cutting-edge today may be outdated in just a few years. If the government rushes to subsidize systems based on today’s solutions, it risks locking public investment into technologies that will soon be surpassed. In effect, Greece may end up using taxpayer money to fund yesterday’s breakthroughs instead of tomorrow’s.
This could distort the market by giving outdated technologies artificial advantages, stifling innovation and setting back the transition to more efficient storage solutions. It’s why the Ministry of Environment and Energy must commission an independent, forward-looking study. Such a study should identify not only the expected LCOS by 2030, but also which technologies—lithium, flow batteries, thermal, sodium-based systems, or others—are likely to prevail in the market, and what risks come with early large-scale subsidies.
There's also a broader assumption driving the storage narrative in Greece: that renewable energy is frequently wasted due to curtailments, and that storage is urgently needed to capture this lost power. But here too, the evidence is lacking. No comprehensive economic analysis has demonstrated that the cost of these curtailments exceeds the cost of storing the energy. Given that some current storage systems can cost up to €160,000 per megawatt-hour, it's fair to ask: is the energy being lost truly valuable enough to justify such a high investment?
The economics don’t add up if the so-called "opportunity cost" of lost renewable power is lower than the cost of storing it. And without firm data to prove otherwise, public subsidies for storage can’t be justified—especially in a country still struggling with high energy prices and tight fiscal conditions.
Energy storage is, without question, a key part of the future energy landscape. But whether Greece implements it wisely depends on the choices made now. Unfortunately, early signs point to a familiar pattern: a rush to subsidize without a long-term plan, potentially paving the way for a new wave of rent-seeking. Once again, public money risks being captured by business interests more focused on securing risk-free returns than on driving real innovation.
