In short
The one with the highest feed-in rate is usually not the best plan for a solar home, because a high feed-in tariff is almost always paired with a higher usage rate or supply charge that costs more than the extra credit earns. In South East Queensland feed-in tariffs are set by each retailer, not regulated, and they change with notice. The plan to want is the one with the lowest net yearly cost on your own import and export, and that is a calculation, not a rate.
How feed-in tariffs work here
In the Energex area a retailer decides what it pays for exported electricity, in cents per kilowatt-hour, plan by plan. Some plans pay a flat rate; some pay a higher rate on the first few kilowatt-hours a day and less after; a few pay by time of day. Regional Queensland has a regulated rate; South East Queensland does not. None of it is taxed, and a feed-in credit is applied to the bill after the charges, so it can never make the bill negative on its own.
The trap
A solar home still imports electricity at night and on cloudy days, and still pays a supply charge every day. A plan that advertises a high feed-in rate typically recovers it through a higher usage rate, a higher supply charge, or both. For most homes, the electricity imported over a year is worth more than the electricity exported, so a few cents more on the export is outweighed by a couple of cents more on the import. The bigger the system and the emptier the house by day, the more the balance tips towards the feed-in rate; the smaller the system and the busier the house, the less it matters.
How to compare properly
- Take your export and your import from a bill, separately. Both are on it.
- Price each plan's charges on the import and its credit on the export, over a full year, because both change with the seasons.
- Ignore the feed-in rate on its own. Compare the net yearly cost.
- Watch the first block. A high rate on the first ten kilowatt-hours a day and a low one after is a different plan for a large system than for a small one.
- Remember it can change. Feed-in tariffs are cut with notice more often than usage rates are raised.
The paid check does exactly that from a bill: every plan's charges on your import and its credit on your export, half hour by half hour, with the plan ranked on the net figure. A solar home that also considers the Solar Sharer Offer should read who actually comes out ahead on it first, because a home with panels usually does not.
Quick answers
Is the solar feed-in tariff regulated in Queensland?
Only in regional Queensland, where the Queensland Competition Authority sets a rate for Ergon's customers. In South East Queensland, the Energex area, every retailer sets its own feed-in tariff plan by plan, and can change it with notice. That is why two plans from the same retailer can pay different rates for the same export.
Should I choose the plan with the highest feed-in tariff?
Not on that alone. Compare the net yearly cost: the plan's charges on what you import minus its credit on what you export. A high feed-in rate is usually paired with higher charges, and for most homes the import is worth more than the export, so the plan with the highest feed-in rate is often not the cheapest overall.
Sources
Official pages this answer relies on. If one of them changes, tell us and we will update the page.
- Energy Made Easy · Australian Energy Regulator
- Solar Sharer Offer · Australian Government, energy.gov.au
- Energy Product Reference Data · Australian Energy Regulator