Energy suppliers in Belgium are not always transparent regarding negative feed-in tariffs, which force some solar panel owners to pay for the electricity they supply to the grid, noted the consumer protection organisation, Testachats, on Tuesday.
The organisation urged the government to intervene to prevent consumers from experiencing unpleasant surprises.
According to an analysis by VRT NWS, 450,000 households risk being affected by these negative tariffs. In 2025 alone, Belgium experienced 229 hours when electricity prices were zero or negative, particularly during sunny periods.
Dynamic contracts, where the rate changes hourly, are directly impacted, but some variable contracts are also affected when the average monthly price fails to cover the supplier’s costs.
Testachats highlighted several transparency issues, noting that indexation formulas are often obscured in fine print or expressed in technical language that is difficult for consumers to understand. Additionally, calculation methods vary among suppliers; some provide an annual estimate, while others only offer recent monthly or quarterly prices, making comparisons difficult.
The organisation also pointed to confusion between fixed and variable tariffs, noting that most feed-in tariffs remain variable even when the consumption contract is fixed, a detail that is rarely emphasised.
Testachats recommended that solar panel owners maximise their use of the energy they produce, calling it the most cost-effective strategy. It further encouraged authorities to make domestic batteries more accessible and to reintroduce incentives for smart energy management.
