Explainer: daily supply charge vs FiT

Introduction

When comparing solar plans, two numbers often cause confusion: the daily supply charge and the feed-in tariff (FiT). One is a fixed cost you pay every day, the other is a credit you earn for exporting solar energy.

This guide explains daily supply charge vs FiT, with examples, definitions, and links to calculators so you can see which matters more for your household.

For background, check What is FiT?.

Key Definitions

• Daily Supply Charge: A fixed fee (e.g. $1/day) just to stay connected to the grid. Paid regardless of usage.

• FiT (Feed-in Tariff): A credit (¢/kWh) for energy you export.

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

Compare plan differences in Retailer Rates.

Worked Example 1 — High Supply Charge, High FiT

• Supply charge: $1.20/day → $36/month

• Export: 500 kWh × 10c FiT = $50 credit

• Net effect = +$14 in credits before import costs

Even with a high supply charge, a good FiT can offset the fee.

Worked Example 2 — Low Supply Charge, Low FiT

• Supply charge: $0.90/day → $27/month

• Export: 500 kWh × 6c FiT = $30 credit

• Net effect = +$3 credit

Here, the lower FiT cancels out the benefit of the lower supply charge.

Worked Example 3 — Usage-Dominated Bill

• Supply charge: $1.10/day → $33/month

• Import: 400 kWh × 28c = $112

• Export: 300 kWh × 7c = $21 credit

• Total = $124 net bill

This shows why supply charges and FiT must be seen in context of usage. Use the FiT Savings Calculator to test your own bill.

Why It Matters

• Retailer comparisons: A “high FiT” plan may also have a higher daily fee.

• Small vs large households: Small users feel supply charges more, while solar-heavy homes benefit more from FiT.

• Payback calculations: Use the Solar ROI & FiT tool to check long-term effects.

Tools for Checking Your Numbers

• FiT Savings Calculator

• Retailer Rates

• Postcode Estimator

• Solar ROI & FiT

• Rate Change Tracker

• Compare FiT by State

FAQs

Q1. Is it better to pick a lower supply charge or higher FiT?
It depends on your exports and imports—always model both.

Q2. Can retailers change the supply charge?
Yes, rates can increase over time. Track them with the Rate Change Tracker.

Q3. Why do plans with high FiT often have high supply charges?
Because retailers balance credits with fixed charges to protect revenue.

Q4. Do all states have similar supply charges?
No, charges vary by state and retailer. See Compare FiT by State.

Conclusion

Daily supply charges and FiT credits both affect your bill. Focusing only on FiT can be misleading if the supply charge is high. The best way to choose a plan is to run your own usage numbers through the calculators and compare across retailers.

Next steps:

• Test your bill with the FiT Savings Calculator

• Compare offers in Retailer Rates

• See state-level averages in Compare FiT by State