Does the sand-store versus heat-pump verdict survive a modelled electricity price instead of the real one?
research/energy-store-modelprice
Does the sand-store vs heat-pump verdict survive a modelled price? Mostly: 32 of 40 cells agree with real prices (21 for the flat merit-order price), but weekly cycling, whose margin is under EUR 0.011/kWh, is wrong in sign in 5 of 5 years; as a charge scheduler the model costs under EUR 0.0011/kWh.
What it found
Feeds the residual-load price model of energy-price-residual (isotonic fit, leave-one-year-out) into the cost model of energy-thermal-real for German day-ahead prices 2015–2019 and compares the house- and district-scale verdicts, sand store against air-source heat pump, with the real-price verdict. The model gives the same verdict as real prices in 32 of 40 scale×cycle×year cells, against 21 of 40 for the flat merit-order price. Daily cycling and monthly and seasonal storage are right in every house-scale cell; weekly cycling, whose real margin is only −0.005 to +0.011 EUR/kWh, is right in 0 of 5 years because the fit misstates each year’s price level (an oracle level restores 4 of 5). Using the model only to pick charge hours while paying the real price costs EUR 0.0004–0.0011/kWh over perfect foresight, against 0.003–0.020 for the flat price. Five years only, realised not forecast inputs, wholesale prices, no data after 2019; the tie band and the charge fraction are assumptions, labelled. All other inputs are from sources.
A figure from its own output
Paper, code and results
More in Energy supply and dense energy storage
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Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.