Rates & sources
DVLA, HMRC fuel advisory rates and manufacturer-published figures. Real-world results vary by driving style.
Source: DVLA / HMRC fuel advisory rates — figures refreshed at the start of each tax year.
When to use this calculator
- When you need a fast estimate before making a bigger decision.
- When you want to compare a few scenarios using the same assumptions.
- When you need a clearer starting point before using a detailed quote or formal document.
- When you want to sanity-check a figure you have seen elsewhere before you rely on it.
- When you are preparing for a conversation with an adviser, supplier, or lender and want to arrive with realistic numbers.
A realistic Ireland planning example
Use these sample inputs as a quick scenario test, then change one variable at a time to compare outcomes.
Annual Miles
10000
Petrol Car MPG
40
Petrol Price Per Litre (€)
€0.30
EV Miles Per kWh
4.5 kW
After entering these figures, review petrol annual cost, ev annual cost and annual saving together rather than in isolation — each metric tells a different part of the story. Then rerun the tool with one input adjusted to see which variable has the biggest effect on all three outputs before you settle on a plan.
How to read your results
Petrol Annual Cost
Use this metric to compare scenarios side by side and understand how changes in the key inputs drive the final outcome. If the figure surprises you, isolate one variable at a time and rerun the calculation to identify which assumption is responsible.
EV Annual Cost
Use this metric to compare scenarios side by side and understand how changes in the key inputs drive the final outcome. If the figure surprises you, isolate one variable at a time and rerun the calculation to identify which assumption is responsible.
Annual Saving
This gives you the recurring yearly benefit of the change or upgrade, which is usually the most practical starting point when comparing options. Divide it by 12 to see the monthly equivalent, or multiply by 5 to get a five-year view of the cumulative gain.
Method & assumptionsAuthoritative sources
This calculator compares the estimated annual running costs of an electric vehicle against a petrol equivalent based on your annual mileage, home electricity rate, petrol price, and the efficiency figures for each vehicle. EV efficiency is expressed in miles per kWh; petrol efficiency in MPG. The comparison covers fuel or energy costs only — it does not include purchase price differences, depreciation, insurance, or servicing, all of which vary significantly by model and driver profile. Public charging costs are not factored into the default calculation; if you rely on public chargers for a portion of your charging, adjust the electricity rate upward accordingly to reflect your blended cost per kWh.
Common mistakes
- !Using optimistic assumptions without testing a more cautious scenario as well.
- !Comparing outputs from different tools without checking that the inputs match.
- !Treating the result as a final quote instead of a planning estimate.
- !Rounding inputs too aggressively, which can produce an output that is noticeably different from your actual situation.
- !Stopping at a single run of the tool rather than adjusting the key variable up and down to understand the range of plausible outcomes.
What to do next
- Try at least one more scenario so you can compare a realistic range instead of a single estimate.
- Use the related calculators below to cross-check the decision from another angle.
- Open one of the linked guides if you need more context before you act on the result.
- Write down the key outputs from your best two or three scenarios so you have something concrete to compare when you make the final decision.
- If the result surprises you, change one input at a time to isolate which variable is driving the outcome before drawing conclusions.
Frequently asked
Use arrow keys to navigate items, Enter or Space to expand/collapse.
End-of-article next steps
Where to go after this calculator
Move to a focused hub instead of restarting your research from scratch.
Best Tools for Small Business
Pick software, validate unit economics, and execute workflows with one connected path.
Open hub →
Startup Resource Center
A startup stack for software decisions, runway math, and practical launch workflows.
Open hub →
Creator Toolkit
Choose creator platforms, calculate revenue targets, and ship assets faster.
Open hub →
Money Management Tools
A practical path for financial product choices, scenario math, and planning utilities.
Open hub →