Portugal diesel prices stay above regulator reference as 'rocket‑plume' effect fuels rise

In Portugal, the price of diesel has remained above the efficient price calculated by the Energy Services Regulatory Authority (ERSE) for six consecutive weeks, with a recent 7‑cent increase at the pump and gasoline up 2.5 cents. Data show the average diesel price has been above the regulator's reference for 42 days in a row.

The market exhibits the so‑called “rocket‑plume” effect: pump prices rise quickly when international oil prices climb but fall slowly when oil prices drop. Environment and Energy Minister Graça Carvalho has asked for an analysis of the price dynamics, though ERSE has found no evidence of irregularities so far. Analysts note that Europe’s deficit in diesel production, previously offset by Russian imports, now relies heavily on Middle‑East supplies after the Ukraine conflict, contributing to price pressure.