FiT and EV charging: best practices

Introduction

As more households adopt electric vehicles (EVs), one common question is: should I charge during the day to use my own solar, or export to the grid and charge later?

This guide explains how FiT and EV charging interact, shows worked examples, and shares best practices to lower your bills.

For background, check What is FiT?.

Key Definitions

• Feed-in Tariff (FiT): Credit earned per kWh of solar exported.

• Self-Consumption: Using your solar energy directly at home or for EV charging.

• Time-of-Use Tariff: Import rates that vary by peak, off-peak, or shoulder hours.

• Net Bill: Import charges + daily supply charges – FiT credits.

Compare offers across retailers with Retailer Rates.

Worked Example 1 — Daytime EV Charging vs Exporting

• Solar export rate: 8c/kWh

• EV charging offset rate: 28c/kWh

• Charging during the day saves 28c per kWh vs only earning 8c if exported.

Conclusion: Self-consumption for EV charging is more valuable than exporting in this case.

Worked Example 2 — Night Charging with Off-Peak Rates

• Off-peak import: 15c/kWh

• Solar FiT export: 10c/kWh
  If you export solar at 10c and charge EV overnight at 15c, the effective cost is 5c/kWh.

Conclusion: Exporting + off-peak charging may be better than daytime charging if FiT is high.

Worked Example 3 — Seasonal Variation

• Summer export: 20 kWh/day surplus × 7c = $1.40 credit

• Winter export: 5 kWh/day surplus × 7c = $0.35 credit
  If EV charging is flexible, shifting to summer daytime hours captures maximum solar use. See Postcode Estimator for local averages.

Best Practices for EV Owners

1. Charge during solar hours when FiT is low and grid rates are high.

2. Export + off-peak charging if your FiT is competitive.

3. Use smart charging to automate charging when solar is abundant.

4. Track changing rates with the Rate Change Tracker.

5. Model ROI using the Solar ROI & FiT tool.

Tools to Optimise Your Charging

• FiT Savings Calculator

• Retailer Rates

• Postcode Estimator

• Solar ROI & FiT

• Rate Change Tracker

• Compare FiT by State

FAQs

Q1. Is it always better to charge during the day?
Not always—it depends on your FiT and off-peak import rates.

Q2. Should I get a smart charger for my EV?
Yes, it allows you to time charging with solar generation or off-peak rates.

Q3. What if my FiT drops after I sign up?
Retailers can adjust FiT. Track changes via the Rate Change Tracker.

Q4. How do EVs affect solar ROI?
More self-consumption usually improves ROI. See Solar ROI & FiT.

Conclusion

FiT and EV charging go hand-in-hand. The best strategy depends on your FiT rate, import tariffs, and EV usage. For most households, daytime charging maximises savings, but exporting plus off-peak charging can work if your FiT is high.

Next steps:

• Run your numbers with the FiT Savings Calculator

• Compare retailer offers in Retailer Rates

• See how FiTs differ by region with Compare FiT by State