WA's DEBS Feed-In Explained: The Two-Rate Solar Buyback

If you're on Synergy in WA and send solar back to the grid, you're paid under the Distributed Energy Buyback Scheme — DEBS. It's not a single flat rate like most states. It's a time-of-use buyback with two very different numbers, and understanding which one applies when is the difference between a system that pays and one that disappoints. This guide walks through how it works and what it should change about how you think about solar in WA.

The two rates, and why the gap matters

Under DEBS with Synergy, exported electricity is bought back at two rates depending on the time of day:

Period	Hours	Buyback rate
Peak	3pm–9pm	10c per kWh
Off-peak	All other hours	2c per kWh

That's a five-fold difference. The catch is obvious the moment you think about when solar actually generates: your panels produce the most around the middle of the day, when the buyback is worth just 2c per kWh. By the time the 10c window opens at 3pm, output is tapering off, and by evening it's often gone entirely. In other words, the generous rate lands exactly when a plain solar system has the least to sell.

Note too that the buyback applies to roughly the first 50 units exported per day — confirm the current cap and your exact rates with Synergy, as terms can change.

Horizon Power is different

If you're in a regional or remote area served by Horizon Power rather than Synergy on the SWIS network, your buyback rates vary by town and don't necessarily mirror the Synergy 10c/2c structure. There's no single Horizon number we can quote here — you'll need to confirm the specific rate for your location before you model anything.

What the structure is really telling you

The two-rate design isn't an accident. WA's grid has an abundance of midday solar and a demand peak in the late afternoon and evening. The 2c daytime rate is a signal that your exported midday solar is worth very little to the network, while the 10c evening rate rewards energy delivered when the grid actually needs it.

For you, that reframes the whole decision. The value isn't in exporting as much as possible — it's in using your own solar during the day (running appliances, pool pumps, hot water, cooling) so you avoid buying grid power, and ideally shifting energy into the evening. That's why DEBS so strongly favours pairing solar with a battery: you store cheap or self-generated daytime energy and either use it or export it into the 10c window after 3pm.

Here's the catch: a battery for DEBS alone may not pay

It's tempting to read "10c evening rate" and conclude a battery is a no-brainer. Be careful. The honest arithmetic is harder than it looks. A battery saves you money in two ways: avoiding evening grid purchases (worth your usage rate, often higher than any feed-in) and selling into the 10c window. But 10c per kWh is still a modest return, and the sums depend heavily on your actual consumption pattern, your retail tariff — Synergy's Midday Saver has super off-peak 9am–3pm and peak 3–9pm, while Home Plan A1 is flat — and how much daytime solar you'd otherwise waste.

Battery paybacks in WA sit around eight years on typical assumptions. Incentives help: the federal Cheaper Home Batteries program (via battery STCs) and the WA Residential Battery Scheme can stack, with the WA scheme indicatively worth roughly $1,300–$3,800 for a usable battery of 5–10kWh — but it makes Virtual Power Plant participation mandatory and has its own eligibility rules. Confirm current figures and terms before you count on them. For a modest electricity user with low evening demand, a battery sized only to harvest DEBS credits can struggle to justify itself. For a household with high evening load, the maths looks much better. The point is: it depends on your numbers, not a brochure's.

How to make DEBS work for your situation

• Shift load into daylight — hot water, dishwasher, washing, pool pump, pre-cooling — so you self-consume instead of exporting at 2c.
• Match your tariff to your habits. Midday Saver's cheap 9am–3pm super off-peak can pair well with daytime solar; a flat plan suits other patterns. Check your actual bill.
• Size solar for self-consumption first, not for maximum export — the 1.5kW single-phase export limit and 2c daytime rate both cap what exporting can earn.
• Model a battery on your real evening usage and against the stacked incentives, not on the headline 10c rate alone.

We don't sell panels, batteries or VPP subscriptions, and we never will. That's the point: we'll model DEBS against your real bill and usage and tell you honestly whether a battery pays for you — or whether it simply doesn't. Sometimes the right answer is to keep your money.

Figures in this guide are current at the date of publication and indicative only — rebate and certificate values change over time (federal battery certificates step down each January and July), and state schemes are amended often. Confirm the current numbers for your situation before you commit. This is general information, not personal financial advice.