Electric Vehicle Charging at Home: WA Tariffs, Costs, and Smart Strategies
Compare Synergy's EV tariffs, calculate home charging costs, and learn how to charge your electric vehicle for almost free with solar in WA.

More Western Australians are switching to electric vehicles every month. But how much does it actually cost to charge at home? And which Synergy tariff gives you the cheapest charging? Let's break it down.
Home Charging Basics
Charging Levels
| Level | Power | Charging Speed | Typical Use | |-------|-------|---------------|-------------| | Level 1 | 2.4 kW (standard outlet) | ~12 km/hour | Emergency/overnight top-up | | Level 2 | 7.4 kW (dedicated circuit) | ~40 km/hour | Recommended home charger | | Level 2 | 22 kW (three-phase) | ~120 km/hour | Fast home charging |
Most Perth households install a Level 2 single-phase charger (7.4 kW) — it can fully charge a typical EV overnight.
Charger Installation Costs
- Charger unit: $800–$2,500 (depending on brand and features)
- Installation: $500–$1,500 (electrical work, dedicated circuit)
- Total typical cost: $1,300–$4,000
Smart chargers (that can schedule charging times) are recommended for tariff optimisation.
The Cost of Charging Your EV
How Much Electricity Does an EV Use?
Most EVs consume between 14–20 kWh per 100km driven. The average Perth household drives about 40 km per day, requiring approximately 6–8 kWh of charging.
Monthly charging for a typical commuter:
- 40 km/day × 30 days = 1,200 km
- At 16 kWh/100km = 192 kWh/month
Charging Cost by Tariff
| Tariff | Rate During Charging | Monthly Cost (192 kWh) | Annual Cost | |--------|---------------------|----------------------|-------------| | A1 (flat rate) | ~30.8 c/kWh | ~$59 | ~$710 | | Midday Saver (midday) | ~15 c/kWh | ~$29 | ~$346 | | Smart Home (off-peak) | ~18 c/kWh | ~$35 | ~$415 | | EV Add-On (super off-peak) | ~10 c/kWh | ~$19 | ~$231 | | Solar self-consumption | $0 | $0 | $0 |
Compare this to petrol: a similar-sized car doing 8L/100km at $1.80/L costs about $173/month — that's $2,074/year.
Synergy's EV Tariffs
EV Add-On Tariff
Synergy offers a dedicated EV charging tariff that provides a super off-peak rate:
- Super off-peak period: Typically midnight to 6am
- Rate: Approximately 10 c/kWh during super off-peak
- Requirements: Separate meter or smart meter capable of recording EV usage
- Best for: Overnight charging when you don't have solar
Smart Home Plan
The Smart Home Plan offers time-of-use pricing that benefits EV owners:
- Off-peak rate (9pm–7am): Lower than A1 flat rate
- No dedicated EV meter required
- Also benefits general household usage
Midday Saver + Solar
If you have solar and charge during the day:
- Grid rate during midday: ~15 c/kWh (if solar isn't enough)
- Solar self-consumption: Effectively free
- Best for: Work-from-home or daytime charging setups
Smart Charging Strategies
Strategy 1: Charge from Solar (Best Savings)
If you have a 6.6kW+ solar system, charge your EV during the day when the sun is shining.
- Cost: $0 (solar self-consumption)
- Requirements: Daytime charging capability (work from home, or plug in when you get home and the sun is still up)
- Smart charger feature: Some chargers can detect excess solar and only charge from surplus
Annual savings vs A1 tariff: ~$710
Strategy 2: EV Add-On Night Charging
For households that drive during the day and charge overnight:
- Schedule charger for midnight–6am
- Super off-peak rate applies
- Cost: ~$231/year for typical commute
- Annual savings vs A1 tariff: ~$479
Strategy 3: Solar + Battery + EV
The ultimate setup:
- Solar charges battery during the day
- Battery powers the house in the evening
- EV charges from grid during super off-peak (cheapest rate)
- Or: EV charges from solar during the day
Combined annual cost for EV charging: As low as $50–$100/year with optimised scheduling.
Sizing Your Solar System for an EV
Adding an EV typically adds 6–8 kWh of daily electricity demand. To cover this with solar:
- Additional solar needed: 2–3 kW of panels
- Current system is 5kW? Upgrade to 7–8kW
- Current system is 6.6kW? May already have enough surplus
Use BillWise's scenario tool to model the exact impact on your bills.
V2H and V2G: The Future
Vehicle-to-Home (V2H) and Vehicle-to-Grid (V2G) technology is emerging:
- V2H: Use your EV battery to power your home during peak hours
- V2G: Export power from your EV back to the grid for credits
- Status in WA: Not widely available yet, but some vehicles (e.g., certain models) support it with compatible chargers
When V2H becomes mainstream, your EV battery (typically 60–100 kWh) could serve as massive home energy storage, far larger than any dedicated home battery.
Charger Recommendations for WA
For Perth households, we recommend:
Budget option:
- Any 7.4kW Mode 3 charger with timer
- Set timer for your cheapest tariff period
- From ~$800 installed
Smart option:
- Solar-aware charger (e.g., Zappi, Tesla Wall Connector)
- Automatically adjusts charging to use excess solar
- From ~$1,500 installed
Premium option:
- Three-phase 22kW charger with solar integration
- Fast charging + full smart control via app
- From ~$2,500 installed
Calculate Your EV Charging Costs
Your actual costs depend on your tariff, solar system, driving patterns, and charger setup. BillWise can model it all:
- Upload your bill — We'll see your current tariff and usage
- Run an EV scenario — Add EV charging to see the impact
- Compare tariff options — Find the cheapest charging tariff for your profile
The bottom line: charging an EV at home in Perth costs a fraction of running a petrol car, and with the right setup, you can charge for almost nothing.
Related Reading
- EV Charging at Home: Everything You Need to Know -- Our complete guide to home EV charging setup, equipment, and installation in WA.
Ready to compare EV charging costs? Calculate your ROI → — includes petrol vs EV comparison with live FuelWatch prices so you can see exactly what switching saves you.
Calculate Your Savings
See how much you could save with solar, batteries, and smart tariff choices


