Calculation Methodology
Comprehensive scientific documentation of equations, energy conversion factors, and vehicle benchmarks powering the VoltSavings engine.
At VoltSavings, we believe computational financial tools must be fully open and auditable. We do not use proprietary "black-box" estimation algorithms. Below is the complete mathematical model, thermodynamic loss considerations, and environmental emission formulas implemented in our client-side software.
Commute Volume & Distance Equations
Total monthly distance is computed by multiplying the single-day round-trip commuting distance by the user's active travel days per month:
Monthly Distance (km) = Daily Commute (km) × Commute Days Per Month
Annual Distance (km) = Monthly Distance × 12
5-Year Distance (km) = Monthly Distance × 60
*Default configuration assumes standard 26 active working/commute days per month (6-day work week) or customizable via daily slider.
Internal Combustion Engine (ICE / Petrol) Model
Liquid fuel volume consumed is derived from distance divided by verified operational fuel economy, combined with recurring monthly mechanical upkeep:
Fuel Volume Consumed (L) = Monthly Distance (km) ÷ Fuel Economy (km/L)
Direct Monthly Fuel Cost = Fuel Volume Consumed (L) × Fuel Price Per Liter
Total Monthly ICE Cost = Direct Monthly Fuel Cost + ICE Monthly Maintenance
ICE Cost Per Kilometer = Total Monthly ICE Cost ÷ Monthly Distance
ICE Maintenance Factors: Periodic motor oil changes (semi-synthetic or full synthetic every 3,000-5,000 km), oil filters, air filters, spark plugs, drive belts, and friction brake pads.
Electric Vehicle (EV) Energy Consumption Model
Electric vehicle energy is calculated in kilowatt-hours (kWh). One kWh equals one standard unit of domestic electricity billed by residential utility providers:
Delivered Battery Energy (kWh) = Monthly Distance (km) ÷ EV Efficiency (km/kWh)
Grid Energy Draw (kWh) = Delivered Battery Energy ÷ Charging Efficiency Factor (η ≈ 0.88)
Direct Monthly Charging Cost = Grid Energy Draw (kWh) × Electricity Tariff Rate
Total Monthly EV Cost = Direct Monthly Charging Cost + EV Monthly Maintenance
EV Cost Per Kilometer = Total Monthly EV Cost ÷ Monthly Distance
Onboard AC-to-DC Conversion Loss (η): Level 1 and Level 2 AC home wall chargers typically exhibit an 10% to 15% thermodynamic conversion loss through onboard rectifiers and thermal battery cooling circuits. Our default presets factor this real-world draw into overall consumption.
Net Retained Cash & Compounding Multi-Year ROI
Net savings quantify the exact discretionary cash retained in the commuter's wallet by avoiding fuel station visits and mechanical servicing:
Monthly Retained Savings = Max(0, Total Monthly ICE Cost - Total Monthly EV Cost)
Percentage Saved (%) = Round((Monthly Retained Savings ÷ Total Monthly ICE Cost) × 100)
Annual Savings (Year 1) = Monthly Retained Savings × 12
3-Year Cumulative Savings = Monthly Retained Savings × 36
5-Year Cumulative Savings = Monthly Retained Savings × 60
Environmental Tailpipe Emissions Avoided
Based on established environmental chemistry standards (US EPA and Intergovernmental Panel on Climate Change guidelines), the combustion of 1 liter of standard automotive gasoline generates approximately 2.31 kilograms of carbon dioxide (CO₂):
Avoided Monthly CO₂ (kg) = Fuel Volume Consumed (Liters) × 2.31 kg CO₂ / Liter
Avoided Annual CO₂ (Tons) = (Avoided Monthly CO₂ × 12) ÷ 1,000
Empirical Vehicle Efficiency Benchmarks (2026 Reference)
To ensure accurate comparisons across diverse vehicle segments, our pre-calibrated presets are anchored against extensive real-world automotive telemetry:
| Vehicle Category | ICE Fuel Economy | EV Efficiency Benchmark | Typical Battery Pack |
|---|---|---|---|
| Electric Scooter (Intra-city) | 50 - 65 km/L (70cc) | 35 - 50 km/kWh | 1.5 - 2.5 kWh |
| Commuter Motorcycle (125cc-150cc) | 38 - 48 km/L | 25 - 35 km/kWh | 3.0 - 5.0 kWh |
| Subcompact Hatchback (1.0L - 1.2L) | 15 - 19 km/L | 7.0 - 8.5 km/kWh | 30 - 45 kWh |
| Mid-size Sedan (1.5L - 2.0L) | 12 - 16 km/L | 5.5 - 7.2 km/kWh | 55 - 75 kWh |
| Compact SUV / Crossover | 9 - 13 km/L | 4.2 - 5.5 km/kWh | 65 - 85 kWh |
| Commercial Light Delivery Van | 7 - 10 km/L (Diesel) | 3.0 - 4.2 km/kWh | 80 - 120 kWh |
Real-World Environmental & Climate Disclosures
While our model provides exact direct mathematical projections, real-world operational efficiency can vary based on external factors:
- Extreme Ambient Temperature: Under severe winter temperatures (below 0°C / 32°F) or scorching heat (above 42°C / 108°F), cabin heating and air conditioning loads can reduce electric driving range by 15% to 25%.
- Aerodynamic Highway Drag: At sustained highway speeds exceeding 110 km/h (68 mph), aerodynamic resistance increases exponentially, slightly favoring liquid fuels on continuous long-distance transit.
- Battery Aging & Capacity Fade: Modern LFP packs degrade gradually (approximately 1% to 1.5% per year). For a full technical analysis of battery chemistry lifecycles, read our EV Battery Lifespan & Degradation Guide.
Test these formulas with your own commute
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