What financing a $6,170 system costs in October 2026
We take one real figure, the Sydney standard 6.6 kW installer offer of $6,170 after STCs (October 2026), and finance all of it. At the lowest of the three advertised rates we read, 6.98 per cent, the repayment is $43.86 a week over three years, $28.13 a week over five and $21.44 over seven. At the highest, 10.49 per cent, five years costs $30.52 a week. Interest and the fees each lender publishes add $1,143 to $2,304 to the price over five years, 19 to 37 per cent of the system. The system itself saves about $1,363 a year in New South Wales, or $26.21 a week, on our standard assumptions. Every number below is reproducible from the formulas in the page source.
The rates we used and where they come from
Three lenders publish a solar or green personal loan rate on their own pages. We read each page in October 2026 and recorded the rate, the comparison rate, the fees and the date the lender gives for the rate. The lowest, 6.98 per cent, is a variable rate on a secured loan from a credit union; the other two are advertised "from" rates for an excellent credit profile, so most borrowers pay more. The comparison rate folds in the published fees on a $30,000 loan over five years and is the figure to compare between lenders; on a $6,170 loan the fixed fees weigh more than the comparison rate suggests, which is why we add them back in dollars below.
| Lender | Product | Rate | Comparison rate | Type | Amount | Term | Published fees | Rate current as at |
|---|---|---|---|---|---|---|---|---|
| Police Credit Union | Solar Eco Loan | 6.98% | 6.98% | variable | $5,000 minimum | up to 7 years | no monthly or annual fees | interest rate current as at 26 May 2026 |
| Brighte | Green Loan | 9.99% (from) | 11.70% | fixed | $2,000 to $65,000 | 2 to 10 years | establishment from $199, $2.99 a week | information and interest rates current as at 1 October 2026 |
| Plenti | Green loan | 10.49% (from) | 11.61% | not stated | $2,000 to $45,000 | 3 to 10 years | $8.99 a month | rates current as at 1 October 2026 |
We could not read a current green loan rate from the four banks we tried; their pages returned errors on the day. No bank rate is used or implied here.
Weekly repayments on $6,170 over 3, 5 and 7 years
Weekly repayment = P x r / (1 - (1 + r)-n), where P is $6,170, r is the annual rate divided by 52 and n is the term in weeks. No deposit, repayments in arrears, fees left out of this table and added in the next one.
| Rate | 3 years | 5 years | 7 years |
|---|---|---|---|
| 6.98% (Police Credit Union) | $43.86 | $28.13 | $21.44 |
| 9.99% (Brighte) | $45.81 | $30.17 | $23.58 |
| 10.49% (Plenti) | $46.14 | $30.52 | $23.95 |
Stretching the term is what makes the weekly figure small: 6.98 per cent over seven years is $21.44 a week against $43.86 over three, and the seven-year loan costs $1,634 in interest against $673.
Total cost of finance against paying cash
Cash is $6,170. Each loan row adds the interest from the formula above and the fees the lender publishes over the term (an establishment fee once, a weekly or monthly account fee for every week or month of the loan). The cheapest route in the table, 6.98 per cent over three years, costs $673 more than cash; the dearest, 10.49 per cent over seven years, costs $3,301 more.
| Rate | Term | Weekly | Total repaid | Interest | Fees over term | Cost of finance | Total against cash $6,170 |
|---|---|---|---|---|---|---|---|
| 6.98% (Police Credit Union) | 3 years | $43.86 | $6,843 | $673 | $0 | $673 | $6,843 |
| 6.98% (Police Credit Union) | 5 years | $28.13 | $7,313 | $1,143 | $0 | $1,143 | $7,313 |
| 6.98% (Police Credit Union) | 7 years | $21.44 | $7,804 | $1,634 | $0 | $1,634 | $7,804 |
| 9.99% (Brighte) | 3 years | $45.81 | $7,147 | $977 | $665 | $1,642 | $7,812 |
| 9.99% (Brighte) | 5 years | $30.17 | $7,845 | $1,675 | $976 | $2,651 | $8,821 |
| 9.99% (Brighte) | 7 years | $23.58 | $8,582 | $2,412 | $1,287 | $3,700 | $9,869 |
| 10.49% (Plenti) | 3 years | $46.14 | $7,198 | $1,028 | $324 | $1,351 | $7,522 |
| 10.49% (Plenti) | 5 years | $30.52 | $7,935 | $1,765 | $539 | $2,304 | $8,474 |
| 10.49% (Plenti) | 7 years | $23.95 | $8,716 | $2,546 | $755 | $3,301 | $9,471 |
The "from $X a week" reversal
An advertisement that says "solar from $30 a week" is quoting a repayment, not a price. Turn it back into a price with P = W x (1 - (1 + r)-n) / r. At 9.99 per cent over five years, $30.17 a week is a $6,170 system, and you hand over $7,845 by the end. The two numbers you need from the seller are the term and the rate; without them the weekly figure cannot be checked.
Worked the other way: "$20 a week" at 9.99 per cent buys a $4,090 system over five years or a $5,234 system over seven; over seven years you repay $7,280. At 6.98 per cent the same $20 over seven years buys $5,756. Ask for the cash price in writing and run the formula; if the cash price is below P, the plan is dearer than the rate implies and the difference is sitting in the system price.
Cash, loan, or the saving the system makes
A 6.6 kW system in Sydney produces about 9,398 kWh a year (1,424 kWh per kW). Using 35 per cent at home at 34c and exporting the rest at 4.0c saves about $1,363 a year, $26.21 a week, held flat for the comparison (no tariff rises, no degradation). Cash recovers $6,170 in 4.5 years. A five-year loan at 6.98 per cent costs $28.13 a week, $1.92 more than the saving, and leaves you behind by $499 when it ends; the system then saves $1,363 a year with nothing to repay. A seven-year loan at the same rate is cash-flow positive from week one, by $4.77 a week, and that is the structure behind every "pays for itself" pitch.
| Option | Upfront | Weekly repayment | Weekly saving | Net weekly | Total paid over term | Position when the term ends |
|---|---|---|---|---|---|---|
| Pay cash | $6,170 | $0 | $26.21 | +$26.21 | $6,170 | 4.5 years to recover the price |
| Loan at 6.98%, 3 years | $0 | $43.86 | $26.21 | -$17.65 | $6,843 | behind by $2,755 at the end of the term |
| Loan at 6.98%, 5 years | $0 | $28.13 | $26.21 | -$1.92 | $7,313 | behind by $499 at the end of the term |
| Loan at 6.98%, 7 years | $0 | $21.44 | $26.21 | +$4.77 | $7,804 | ahead by $1,735 at the end of the term |
| Loan at 9.99%, 3 years | $0 | $45.81 | $26.21 | -$19.60 | $7,812 | behind by $3,724 at the end of the term |
| Loan at 9.99%, 5 years | $0 | $30.17 | $26.21 | -$3.96 | $8,821 | behind by $2,007 at the end of the term |
| Loan at 9.99%, 7 years | $0 | $23.58 | $26.21 | +$2.63 | $9,869 | behind by $330 at the end of the term |
| Loan at 10.49%, 3 years | $0 | $46.14 | $26.21 | -$19.93 | $7,522 | behind by $3,434 at the end of the term |
| Loan at 10.49%, 5 years | $0 | $30.52 | $26.21 | -$4.31 | $8,474 | behind by $1,660 at the end of the term |
| Loan at 10.49%, 7 years | $0 | $23.95 | $26.21 | +$2.26 | $9,471 | ahead by $68 at the end of the term |
Position = saving over the term minus everything paid. Savings depend on your usage pattern; the 35 per cent self-consumption share is the site assumption and is explained on the methodology page.
State and territory solar loans, verified 27 October 2026
Four jurisdictions have a government loan you can put toward solar or a battery; four have nothing open. Each row was read on the government's own page on the date shown. New South Wales lends $2,000 to $15,000 at zero interest over up to ten years to households earning up to $210,000. Victoria offers an interest-free loan of up to $1,400 alongside the $1,400 panel rebate, repaid over four years at $29.17 a month. Western Australia lends up to $10,000 at no interest, but only with a battery under the Residential Battery Scheme. The ACT lends $2,000 to $20,000 at 3 per cent and excludes solar panels unless you hold a concession card. Tasmania's loan closed on 1 September 2025; Queensland, South Australia and the Northern Territory have no loan scheme.
| State | Scheme | Status | Amount | Term | Rate | Income test | Checked on |
|---|---|---|---|---|---|---|---|
| NSW | Home Energy Saver: zero-interest loan | open | Zero-interest loan of at least $2,000 and up to $15,000 per property | up to 10 years | 0% | Combined taxable household income of up to $210,000 a year | 2026-10-27 |
| VIC | Solar panel (PV) interest-free loan | open | Up to $1,400 interest-free | 4 years | 0% | As for PV rebate: combined household taxable income less than $150,000 | 2026-10-27 |
| VIC | Solar battery interest-free loan | closed | Was an interest-free loan with repayments of up to $183.34 per month over 4 years | was 4 years | 0% | none stated | 2026-10-27 |
| QLD | No state loan scheme | none open | none | none | none | none | 2026-10-27 |
| WA | Residential Battery Scheme no-interest loan | open | Up to $10,000 | up to 10 years | 0% | Combined annual household income of less than $210,000 | 2026-10-27 |
| SA | No state loan scheme | none open | none | none | none | none | 2026-10-27 |
| TAS | Energy Saver Loan Scheme | closed | Was 0% loans of $500 to $10,000 | was 1 to 3 years | 0% | none stated | 2026-10-27 |
| ACT | Sustainable Household Scheme (SHS) loan | open | Loan of $2,000 to $20,000 | up to 10 years | 3% | none stated | 2026-10-27 |
| ACT | Home Energy Support Program (HESP) rebates and zero-interest loan | not stated on the page | Zero-interest loan of up to $10,000 (with rebates of up to $5,000) | not stated | 0% (loan part) | Concession card based (Pensioner Concession Card, DVA Gold Card or Health Care Card) | 2026-10-27 |
| NT | No state loan scheme | none open | none | none | none | none | 2026-10-27 |
A zero-interest government loan beats every lender rate above: the NSW loan on the full $6,170 costs nothing in interest, so the cash and loan columns are the same $6,170. Full scheme detail is on the NSW, Victorian and WA rebate pages.
Green loan, retailer plan or redraw: what to check
- Comparison rate, not headline rate. "From" rates apply to the best credit profiles; ask for your rate in writing before you sign the solar contract.
- Fees in dollars. A weekly account fee of a few dollars is several hundred dollars over five years on a loan this size; the table above shows them.
- Term. The weekly figure falls with a longer term and the interest rises; compare total repaid.
- Cash price first. Get the installer's cash price for the same system before you discuss finance, then apply the reversal formula to any plan.
- Early repayment. All three lenders above state no early repayment fee; a zero-interest government loan has no interest to save, so paying it early gains nothing.
- Redraw. Adding the system to a home loan is usually the lowest rate available to a homeowner, but spread over the life of the mortgage the interest can exceed a short personal loan; repay the amount within a few years.
Before you finance anything, run the quote through the quote check: a dear system on cheap finance is still a dear system. City prices are on the Sydney and Melbourne pages, and the full price picture on the solar panel cost guide.
Solar finance questions
How much does it cost to finance a 6.6 kW solar system?
$28.13 to $30.52 a week over five years for the $6,170 Sydney standard 6.6 kW offer, at advertised rates of 6.98 to 10.49 per cent read from lender pages in October 2026. Interest and published fees add $1,143 to $2,304 to the cash price.
Is there an interest-free solar loan in Australia?
$15,000 is the largest zero-interest loan open on 27 October 2026: the NSW Home Energy Saver loan of $2,000 to $15,000 over up to ten years for households earning up to $210,000. Victoria lends up to $1,400 interest-free with its panel rebate, and WA lends up to $10,000 with a battery. Queensland, South Australia, Tasmania and the Northern Territory have no loan open; the ACT loan charges 3 per cent and excludes panels.
What does "solar from $30 a week" mean?
$30.17 a week at 9.99 per cent over five years is a $6,170 system, and $7,845 repaid in total. The weekly figure is a repayment, not a price; you need the rate and the term to turn it back into one, using P = W x (1 - (1 + r) to the power of minus n) / r.
Is it cheaper to pay cash for solar?
$1,143 to $2,304 is what a five-year loan adds to a $6,170 system at the rates we read, so cash is cheaper by that amount. The exception is a zero-interest government loan, which costs the same as cash and keeps your money in the offset account.
Does the solar saving cover the loan repayment?
$26.21 a week is the saving a 6.6 kW system makes in Sydney on our assumptions ($1,363 a year). A five-year loan at 6.98 per cent costs $28.13 a week, slightly more than the saving; a seven-year loan at the same rate costs $21.44 and is covered, at the price of $1,634 in interest.
What interest rate do green loans charge for solar?
6.98 to 10.49 per cent were the advertised rates on the three lender pages we read in October 2026, with comparison rates of 6.98 to 11.70 per cent. The two "from" rates apply to excellent credit profiles; most borrowers are offered more.