Renewables Growth Cut Spain’s Electricity Bills by 24.2% – What It Means for Solar

For years, the argument for renewables has been environmental. Now, the economic case has become undeniable. A new report from Positive Money, titled Towards Cheaper Electricity, provides compelling evidence: between 2023 and 2025, the expansion of renewable energy capacity reduced wholesale electricity prices by an average of 24.2% across the countries analysed. In Spain and Portugal, exposure to gas price volatility dropped by 53% compared to three years ago.

At Sunlink (Xiamen), we see this as a powerful validation of the solar-led energy transition – and a roadmap for other markets still trapped by fossil fuel dependency.

Two Mechanisms, One Outcome: Cheaper Power
The report identifies two ways renewables lower electricity prices within Europe’s marginal pricing system:

Displacement effect – Renewables generate at near‑zero variable cost and displace more expensive gas‑fired plants. The most expensive plant still needed to meet demand sets the marginal price. As more renewables enter, that marginal plant is cheaper – so the wholesale price falls.

Price‑setting effect – When renewable output covers a sufficiently large share of demand, renewables themselves (with near‑zero marginal cost) can become the price‑setting technology. This effect strengthens as penetration rises, especially in systems with low gas dependence or abundant low‑cost nuclear/hydro.

Spain exemplifies this shift. In 2018, wholesale electricity prices closely tracked gas prices. By 2025, that correlation had weakened significantly – wholesale prices frequently fell below levels implied by gas costs, even when gas itself remained volatile.

Why This Changes the Investment Landscape
For solar developers and asset owners, this decoupling has profound implications:

Revenue certainty rises – Electricity prices are becoming less dependent on geopolitical gas shocks. This reduces the risk profile of merchant solar projects, making them more bankable without long‑term PPAs (though PPAs remain valuable).

Capture prices matter more – As midday solar floods the market, intraday price swings widen. Spain now experiences very low (even zero or negative) midday prices and higher evening peaks. This means energy yield (kWh) is no longer the only metric – timing determines revenue. Solar projects paired with storage can shift generation to evening peaks, capturing higher prices.

The gas decoupling is incomplete – but accelerating – The report notes that gas still influences pricing in many European markets due to grid interconnection. However, as renewables share grows, the decoupling will deepen. Markets that lag behind (e.g., Italy, still highly gas‑dependent) face higher prices and greater volatility – creating a competitive disadvantage for industry.

The Storage Opportunity
Positive Money highlights that large‑scale renewable deployment must be accompanied by greater system flexibility. Spain’s widening intraday price swings – extremely low at midday, high in the evening – are creating “increasingly strong economic incentives for battery storage”.

For Sunlink, this is a clear signal: solar‑plus‑storage is no longer a niche solution. In markets like Spain, building a solar plant without storage leaves significant revenue on the table. Batteries capture otherwise‑curtailed midday production and sell it into the higher‑price evening peak. This business case will only strengthen as renewables penetration continues to rise.

Our Perspective at Sunlink
As a one‑stop PV system solution provider, we help customers navigate exactly these market dynamics. Here is our takeaway for different stakeholders:

For utility‑scale developers: When modelling revenue, do not rely on flat capture price assumptions. Use granular, forward‑looking price curves that reflect rising solar penetration and widening intraday spreads. Factor storage into your initial design – even modest storage (1–2 hours) can dramatically improve merchant returns.

For C&I and residential customers: Falling wholesale prices eventually translate into lower retail bills, but time‑of‑use tariffs become more important. Pairing solar with a battery (and smart energy management) allows you to self‑consume more and avoid expensive peak tariffs. The payback period for storage is shortening as intraday price volatility increases.

For policymakers in other regions: Spain’s experience proves that aggressive renewables deployment is not just an emissions strategy – it is a cost‑of‑living and industrial competitiveness strategy. Reducing gas exposure protects consumers and industry from imported inflation. The 53% drop in gas price volatility exposure is a metric every energy‑importing country should aim for.

Conclusion

The Positive Money report confirms what many in the solar industry have long argued: renewables lower electricity bills. Spain’s 24.2% price reduction over two years is not an accident – it is the direct result of deploying wind and solar at scale. As gas prices remain structurally uncertain, the economic advantage of solar will only grow.

At Sunlink, we are committed to delivering PV solutions that maximise both energy output and economic value – whether through advanced trackers, bifacial modules, or integrated storage. The transition to cheaper, cleaner electricity is already happening. The question is not if your market will follow Spain’s path, but when – and whether you will be ready.

Ready to capture the value of solar in a low‑gas‑exposure market? Contact Sunlink to explore our tailored PV and storage solutions.