New tool calculates where to refuel for less, accounting for distance and consumption
A student from the Faculty of Engineering at the University of Porto (FEUP) has launched a platform that answers a question many drivers ask before filling up: where is it actually cheapest to refuel? The tool, called Gasovia, goes beyond listing pump prices. It calculates the real cost of reaching a petrol station by factoring in the distance, the vehicle's fuel consumption, and any discounts available.
"This project came from a very simple question: where is the cheapest place to refuel?" the FEUP student told RTP. "The main goal is to make prices accessible to everyone."
The platform works across Portugal, Spain and France. It pulls data from official sources — in Portugal, from the Directorate-General for Energy and Geology (DGEG), the government body responsible for energy policy and fuel price reporting.
Prices fell this week, but remain high
Fuel prices dropped at the start of this week, matching earlier forecasts. According to DGEG figures updated on Tuesday, simple diesel fell to 2.186€ per litre, down from 2.22€ on Friday. Simple 95 petrol dropped to 2.099€ per litre, down from 2.115€ over the same period. Diesel became €0.034 cheaper per litre, while petrol fell by €0.016.
These averages are calculated from prices reported by fuel stations, weighted by sales volumes from the most recent known period. They incorporate discounts already applied at the pump, such as fleet cards and other loyalty programmes.
Government discounts are shrinking
While prices edged down, the government has been scaling back the discount on the Tax on Petroleum and Energy Products (ISP). In early September, state support totalled around 23 cents per litre for both petrol and diesel. By the end of the month, the ISP reduction applied to diesel had fallen to 0.85 cents per litre, and for petrol to just 0.07 cents.
This matters because a full tank of diesel for a typical family car — around 50 litres — now costs roughly 109€, compared with 111€ last week. That saving of about 2€ barely covers a coffee, but it adds up over a year of weekly fill-ups, putting roughly 100€ back in a driver's pocket.
Cross-border gap persists
Portuguese drivers continue to pay more than their Spanish neighbours. Data from late September shows petrol in Spain at roughly 1.914€ per litre and diesel at 1.905€ — more than 18 cents cheaper per litre than in Portugal. France tells a different story: petrol averages around 2.15€ per litre, but diesel ranges from 2.399€ to 2.63€, making it significantly more expensive than in Portugal.
For someone living near the border, crossing into Spain for fuel can mean saving around 9€ on a 50-litre tank. Gasovia's trip planner now includes Spanish stations, making cross-border refuelling easier to calculate.
Minister calls for coordinated EU response
Portugal's Minister of Energy, Maria da Graça Carvalho, has pressed the European Union in Brussels to take a more active role in the current fuel crisis. Speaking after meetings with European Commission officials on 28 and 29 September, she called for a coordinated response similar to the EU's action during the 2022 energy crisis following Russia's invasion of Ukraine.
"We hope Europe will be more involved in this crisis, as it was in 2022," Maria da Graça Carvalho said. "One dimension is aid, the other is coordinating measures at the level of member states to preserve the integrity of the internal market and reduce competition problems."
The minister warned that divergent national responses risk fragmenting the single market. Flexible EU rules on state aid allow governments to support companies hit by rising prices, but different budget capacities across member states can create competitive imbalances. In Portugal, industries struggling to switch from gas to electricity — such as ceramics and glass — are particularly exposed.
Maria da Graça Carvalho expects the fuel crisis to be a central topic at the European Council meeting in October, when heads of state and government gather in Brussels.
How Gasovia works for drivers
The platform, available in Portuguese, English, French and Spanish, offers several features designed for everyday use:
• Real-time price map: Shows nearby stations and current pump prices.
• Trip cost planner: Estimates fuel costs for a route, based on distance and vehicle consumption.
• Price trends: Displays historical data to help users spot the best times to refuel.
• Brand rankings: Lists which chains offer the lowest prices by region.
The tool factors in discounts available at stations, including fleet cards and loyalty schemes. However, specific programmes — such as the Automóvel Clube de Portugal's partnership with BP, which offers members 13 cents per litre off on weekends and up to 18 cents off on the 15th of each month — may require users to input their eligibility manually.
For a driver in Lisboa comparing stations within a 10km radius, the difference between the cheapest and most expensive option can exceed 10 cents per litre. On a 50-litre fill-up, that's 5€ saved just by checking before leaving home.
