Electricity prices in France turn negative as renewable energy floods the grid
France’s wholesale electricity prices briefly went negative after a surge in solar and wind output coincided with low demand, forcing some nuclear reactors to power down and exposing limits in cross‑border transmission capacity. Commenters debate what this means for the future energy mix: whether nuclear remains viable when its capacity factor is eroded by renewables, and how much to rely instead on cheap wind/solar plus large-scale storage, flexible demand, and better interconnectors. There is broad agreement that negative prices highlight both market design issues and opportunities for batteries, pumped hydro, and price-responsive loads such as EV charging or industrial processes.
Cross‑border transmission and price gaps
- France’s negative day‑ahead price vs positive German price sparks discussion of building more interconnectors.
- Back‑of‑envelope: 250 km, ~€2M/km, 2 GW capacity → ~€500M capex; with a ~€13/MWh spread, payback in a few years. Others note competition and narrowing spreads may erode this.
- Several comments say the real constraint is limited interconnector capacity, not transmission losses.
- Some argue incentives are already aligned, so profitable interconnect projects will happen without extra intervention.
Nuclear flexibility and cost effectiveness
- Disagreement over whether French reactors can load‑follow; some say they regularly do, others claim nuclear is economically poor for load‑following and even as baseload in some contexts.
- Example data from Ontario used to argue nuclear can be cost‑competitive baseload; others say high overnight fixed‑price structures hide inefficiencies.
- Point raised that as renewables grow, nuclear capacity factors fall, effectively raising nuclear LCOE unless system is planned carefully.
Renewables, negative prices, and storage
- Negative prices are framed by some as a clear signal for more storage (grid batteries, pumped hydro, EVs, domestic batteries) and more interconnects.
- Others worry negative prices de‑incentivize investment in generation and indicate “useless capacity,” ultimately favoring fossil backup in winter and long low‑renewable periods.
- Examples from California, the UK, Australia, NL, and others: frequent negative or near‑zero prices already driving storage, curtailment, and flexibility products.
Impact on consumers
- Retail customers typically see fixed or time‑of‑use tariffs; spot negatives rarely translate directly to being paid for consumption.
- Some markets offer dynamic tariffs or EV‑optimized tariffs that exploit cheap/negative hours to charge cars or home batteries.
Nuclear vs renewables debate
- Long thread on whether nuclear is “the future” given France’s prices are not “too cheap to meter.”
- Arguments against nuclear: high capex and opex, long builds, water constraints, political and safety overhead, need for heavy state support.
- Arguments for nuclear: reliable low‑carbon baseload compared to intermittent renewables; France as proof of deep decarbonization.
- Several predict renewables + storage will outcompete nuclear on cost; others stress the need for a diversified mix and caution against assuming storage prices will always fall.
Market design and flexibility
- Econ discussion: with near‑zero marginal cost generators, pure per‑kWh pricing struggles to recover fixed costs.
- Proposals: capacity markets and paying for available power, not just energy; more flexible demand (industry, EV charging, hot‑water loads) tied to real‑time prices.
- Some see intermittent “free” power as an opportunity for flexible industrial processes; others doubt many industries can economically operate on highly variable schedules.