Road Trip Fuel Cost & Stop Planner

Road Trip Fuel Planning Guide

What's the difference between Real-World and Official Fuel Economy?

Official WLTP fuel economy figures consistently overstate real-world performance by 10-25%. A car rated at 60 mpg typically delivers 45-50 mpg in mixed real-world driving. Motorway driving at 70 mph is less efficient than the WLTP test cycle (which assumes varied speeds). Add 15-20% to official consumption figures for realistic planning, especially for long motorway journeys. Factors increasing consumption: high speed (aerodynamic drag increases with speed squared — 80 mph uses approximately 25%

What's the key thing to understand about Fuel Stop Planning?

Do not let the fuel level drop below one quarter of the tank on a long journey — fuel pumps in fuel-injected cars sit in the fuel tank and are cooled by the fuel. Running near empty can overheat and damage the pump. For motorway journeys: fill up before joining the motorway — motorway service station fuel is typically 8-15p/litre more expensive than supermarket forecourts. Apps like Waze and GasBuddy show current fuel prices at stations near your route. For electric vehicles: plan charging stops around the route in advance, since rural areas and motorways can have patchy charger coverage compared to urban areas.

What's the difference between Petrol and Diesel vs Electric Running Costs?

Real-world running cost comparison per 100 miles (UK 2024): petrol car averaging 40 mpg at 154p/L: approximately £17.50. Diesel car averaging 50 mpg at 161p/L: approximately £14.60. Hybrid averaging 55 mpg: approximately £13.30. Electric car at 3.5 miles/kWh on home tariff (24p/kWh): approximately £6.80. Electric at public rapid chargers (75-85p/kWh): approximately £21-24. The EV advantage evaporates entirely when using public rapid chargers — home charging is where EV economics work. For long trips relying mainly on public charging, the cost advantage of an EV over petrol can shrink considerably or disappear entirely.

What's the key thing to understand about Total Trip Budget Beyond Fuel?

Fuel is typically 30-50% of total road trip cost. Other major costs: accommodation (typically the largest single cost on multi-day trips). Tolls: France A-roads are tolled (budget £50-80 per 1,000km). Spain and Portugal also have tolls. UK has no motorway tolls except the M6 Toll. Food and drink: plan snacks and a flask to avoid service station food markups (2-3× supermarket prices). Parking: city centre parking in Europe £5-25/day. Travel insurance. Breakdown cover. EHIC/GHIC for European healthcare cover — a free, simple way to reduce the risk of unexpected medical costs while travelling within Europe.