Dynamic Energy Tariff Implications for the Ex-Ante, Operational Energy (Cost) Evaluation of Residential Storage and Production Options

Dynamic energy tariffs increasingly mirror renewable generation and market conditions, yet most techno-economic assessments of residential retrofit and flexibility measures still rely on simplified, static tariffs, risking-biassed cost estimates. This study systematically maps energy tariff structures across three classification tables, showing that dynamic and weather-responsive tariffs are underrepresented in ex-ante building energy modelling. Building on this gap, four ex-ante tariff-modelling methods are developed and validated, namely a fixed tariff, a time-of-use (ToU) tariff, a weather-dependent real-time-pricing (RTP) mechanism grounded in a residual-load proxy, and a capacity-based network tariff, illustrated for the Flemish context. The RTP mechanism is calibrated against two years of Belgian day-ahead prices (ENTSO-E) and Elia demand, as well as PV- and wind-generation data, reaching a monthly correlation of ρ = 0.78 (hourly ρ = 0.43, excluding 2022) and ρ = 0.71 for the final quantile-mapped tariffs, using only weather data (.epw) and three calibratable parameters. An illustrative building-level application shows that, for an identical unoptimised demand profile, a weather-driven RTP tariff changes the projected annual electricity cost by roughly 33–44%, against only 1–3% for a static ToU tariff, confirming that tariff structure must be an explicit ex-ante modelling choice.