💰 1. Fuel, Electricity & 2027 Road User Charge (RUC) Model
The financial engine compares the true running costs of petrol, hybrid, plug-in hybrid (PHEV), and battery electric vehicles (BEVs) based on Australian Design Rules (ADR 81/02) and actual retail energy rates.
A. Petrol & Hybrid Baseline Annual Cost
Annual Petrol Spend ($) = (Annual Distance / 100) × Fuel Consumption (L/100km) × Petrol Price ($/L)
- Toyota Hybrid Baseline (4.6 L/100km): Standard real-world benchmark for modern series-parallel hybrids (e.g. Toyota RAV4 Hybrid / Corolla Hybrid).
- Small Hatch / Sedan (6.5 L/100km): Compact petrol passenger car (e.g. Mazda 3, Hyundai i30).
- Mid-Size SUV (8.2 L/100km): Australia's most popular family vehicle segment (e.g. Mazda CX-5, Toyota RAV4 2.5L Petrol, Hyundai Tucson).
- Large SUV / Ute (11.0 L/100km): Dual-cab diesel/petrol utes and full-size 4WDs (e.g. Ford Ranger, Toyota HiLux, LandCruiser Prado).
B. EV & PHEV Electricity Cost
BEV Electricity Cost ($) = (Annual km / 100) × Efficiency (kWh/100km) × [(Home% × Home Rate) + (Public% × Public Rate)]
PHEV Total Cost ($) = [Electric km × Home Rate] + [Petrol km × 5.0 L/100km × Petrol Price]
- Free Rooftop Solar (0.0¢/kWh): Marginal daytime charging cost when soaking excess self-generated solar.
- EV Night Saver Plans (8.0¢/kWh): Off-peak tariffs offered by Australian retailers (OVO, AGL, Origin) during low-demand midnight hours (12am–6am).
- Standard Flat Grid (28.0¢/kWh): Average Australian residential 24/7 retail tariff.
- Public DC Fast Charging (55.0¢/kWh): Highway fast-charging commercial network average (Tesla Supercharger, Chargefox, Evie).
C. The 2027 Road User Charge (RUC) Policy Framework
Following the landmark High Court decision in Vanderstock v Victoria [2023] HCA 30, state-based EV distance taxes were ruled unconstitutional. The Australian Federal Treasury and State Governments are developing a unified national distance-based road funding framework intended for 2027:
- BEVs (Battery Electric): Modeled at 3.095 ¢/km ($30.95 per 1,000 km).
- PHEVs (Plug-in Hybrid): Modeled at 2.476 ¢/km ($24.76 per 1,000 km), reflecting that PHEV drivers already pay fuel excise on their petrol driving portion.
For official state government background, see the NSW Government Electric Vehicle Strategy Road User Charge Guide ↗.
⚡ 2. How Solar, Wind, and Coal Electricity are Calculated
A common misconception is that charging an EV from the grid is just as dirty as burning coal. In reality, the carbon intensity of the Australian National Electricity Market (NEM) changes drastically throughout the 24-hour day:
| Charging Scenario |
Primary Power Source |
Carbon Factor (kg CO₂e/kWh) |
How It Works in Practice |
| ☀️ 0.0¢ Free Rooftop Solar |
Direct Rooftop PV |
0.04 kg/kWh |
Amortised solar panel manufacturing footprint. 100% zero tailpipe or grid fuel emissions. |
| 🌤️ 0¢–5¢ Midday Solar Soak |
Midday Grid Solar Sponge |
0.15 kg/kWh |
10am–3pm solar flood across NEM grid. High renewable penetration (70%–100% instantaneous in SA/VIC/QLD). |
| 🌙 8.0¢ EV Night Plan |
Overnight Wind + Baseload |
0.32 kg/kWh |
12am–6am off-peak charging. High contribution from overnight wind farms and steady baseload. |
| 🔌 28.0¢ Standard Flat Grid |
Full NEM Average Mix |
0.58 kg/kWh |
Standard 24-hour average mix across coal, gas peakers, solar, wind, and hydro. |
| ⚡ 55.0¢ Public DC Fast Charging |
Commercial Peak Grid |
0.62 kg/kWh |
High-demand commercial fast-charging demand profile. |
💡 Concrete Driving Example (15,000 km/year @ 15.5 kWh/100km = 2,325 kWh/year):
- Charged with Rooftop Solar (0¢): Produces just 93 kg CO₂/year.
- Charged on EV Night Saver Plan (8¢): Produces 744 kg CO₂/year.
- Charged 100% on Flat Average Grid (28¢): Produces 1,348 kg CO₂/year.
- Equivalent Petrol SUV (8.2L/100km): Produces 3,505 kg CO₂/year (Scope 1 + 3).
Even on standard Australian coal/gas grid electricity, the EV cuts operational driving carbon by over 61%!
🌿 3. Cradle-to-Grave Life Cycle Carbon Assessment (EVC Model)
To answer the question *"What about the pollution to make the battery?"*, the Techwheel calculator adopts the **Electric Vehicle Council (EVC) Lifecycle Emissions Model**.
A. Manufacturing (Embodied) Battery Carbon Debt
Building a vehicle chassis creates ~5,500 kg CO₂e for both petrol and electric cars. An EV incurs an upfront manufacturing deficit due to battery cell production:
Battery Carbon Deficit (kg CO2e) = Battery Pack Capacity (kWh) × 75.0 kg CO2e/kWh
- Small EV (50 kWh): +3,750 kg CO₂e manufacturing debt.
- Mid-Size EV (60 kWh): +4,500 kg CO₂e manufacturing debt.
- Large EV (90 kWh): +6,750 kg CO₂e manufacturing debt.
- Plug-in Hybrid PHEV (18 kWh): +1,350 kg CO₂e manufacturing debt.
B. The Battery Footprint Payoff Point
Payoff Time (Years) = Battery Build Deficit (kg) / Annual Net CO2 Avoided (kg/yr)
Because driving electric is so clean, a typical 60 kWh EV pays off its entire battery manufacturing debt in 1.3 to 1.8 years of normal Australian driving (~20,000 to ~27,000 km).
C. Over 200,000 km Total Driving Comparison
| Vehicle Type |
Manufacturing + Battery Debt |
200,000 km Fuel / Electricity |
Total Cradle-to-Grave Carbon |
Multiplier vs EV |
| Petrol SUV (8.2 L/100km) |
5.9 tonnes |
46.7 tonnes (16,400 Litres) |
52.6 tonnes CO₂e |
3.7× More Carbon |
| Toyota Hybrid (4.6 L/100km) |
6.2 tonnes |
26.2 tonnes (9,200 Litres) |
32.4 tonnes CO₂e |
2.3× More Carbon |
| PHEV (18 kWh, 50% EV) |
7.3 tonnes |
14.6 tonnes (Elec + Petrol) |
21.9 tonnes CO₂e |
1.5× More Carbon |
| Battery EV (60 kWh, Solar/Night) |
10.4 tonnes |
3.9 tonnes (31,000 kWh) |
14.3 tonnes CO₂e |
Baseline Clean |
🫁 4. Urban Public Health & Air Pollution Model
Unlike power plants located outside metropolitan areas, vehicle exhaust pipes release toxic gases directly into residential streets, pedestrian crossings, and school zones.
A. Australian Epidemiological Research
Landmark studies from Melbourne Climate Futures (University of Melbourne, 2023) and the Australian Chronic Disease Prevention Alliance (ACDPA) reveal:
- 11,105 premature adult deaths every year in Australia linked to vehicle emissions (approx. 10× the national road accident toll).
- 19,050 hospital admissions annually (12,210 cardiovascular + 6,840 respiratory).
- 66,000 active childhood asthma cases triggered by traffic exhaust gases (principally NO₂ and PM₂.₅ fine particulate soot).
B. Health Savings & Driver Ratios
Annual Health Savings ($) = Annual Electric km × $0.028/km ($420/yr for 15,000 km)
Hospital Ratio: 19,050 hospitalisations / 15,000,000 light vehicles = 1 in 78 Drivers prevents 1 full hospital admission over 10 years
📚 5. Key Facts: EV & PHEV Economics & Policy FAQs
How does PHEV charging and petrol hybrid operation work?
Plug-in Hybrids (PHEVs) are charged at home using solar or off-peak electricity for everyday city commuting (e.g. 50% of annual km). For longer highway trips, they seamlessly switch to their onboard petrol hybrid engine (consuming roughly 5.0 L/100km). Because PHEVs charge at home, they don't require expensive public DC Superchargers.
Why does home solar charging make driving almost free?
When you charge during daylight hours from rooftop solar, your marginal energy cost is 0¢ to 8¢/kWh (reflecting avoided feed-in tariff). At 15.5 kWh/100km, 100 km of driving costs $0.00 to $1.24 — compared to $16.00+ for a petrol car.
What is the proposed Road User Charge (RUC)?
Australian treasuries proposed replacing petrol fuel excise with a distance charge: 3.095 ¢/km for pure BEVs and 2.476 ¢/km for PHEVs. Even with RUC fully added, electric and plug-in hybrid driving remains significantly cheaper than petrol.