“STCs and no interest loans” and “STC discount and pay later” are really one question: how does the federal discount interact with the way you pay? The answer is that they are separate, and the order matters.
The order of events
- The installer quotes a price.
- The STC discount is deducted at the point of sale. See the upfront discount.
- You pay the remaining amount, in cash, with a loan or through a pay later product.
If a lender finances the system, the loan should be for the amount after the STC discount. If a loan covers the gross price and the STC value is “returned” later, treat that as a red flag and ask for the repayment schedule in writing.
Government zero-interest loans
At the time of writing:
- The ACT’s Sustainable Household Scheme has offered zero-interest loans for household electrification, including batteries. See the ACT scheme.
- Victoria’s Solar Battery Loan and Tasmania’s Energy Saver Loan have closed.
- Queensland’s Battery Booster and the NT battery scheme have also closed.
Always confirm eligibility, interest terms and limits on the scheme’s official page, because they change. Government loans are separate from STCs and usually do not reduce the number of certificates you receive.
Pay later and buy-now-pay-later plans
Some solar retailers offer interest-free periods through a financier. These products are convenient but need care:
- Fees. Establishment or monthly fees can make “interest free” costly.
- Deferred interest. If the balance is not paid within the term, interest may be charged from day one.
- Credit checks. A large balance can affect your borrowing capacity.
- Responsibility. The loan is a separate contract from the installation, so a problem with the installer does not stop repayments.
What this means for you
Get the STC count and value on the quote first, then decide how to pay. A lender should see the same invoice you do. For other finance types, such as green loans and home equity, see STCs and solar finance. For state incentives that sit alongside, see stacking STCs with state rebates. The homeowners guide covers the wider picture. Installers who offer finance can see how certificates settle in how it works and on pricing.
Questions to put to any lender
Ask whether the loan amount matches the post-discount invoice, when the installer is paid, what happens if the installation is delayed or the STC claim is later rejected, and whether you can repay early without a fee. Get the answers by email. A lender who is relaxed about these questions is usually a safer bet than one who rushes you to sign on the day.