Q&A: Using solar first

The solar feed-in tariff being offered by most companies is the minimum 8 c/kWh. However, if you are home during daylight hours and are using electricity at the same time that your solar panels are producing, does your household use that solar power (in effect) and so save you being charged at 29 c/kWh?

—Ray Leerson

Yes, at each instant your solar generation will take the path of least resistance. Your household appliances are supplied first (offsetting 29 c/kWh as per your tariff), then any excess is pushed to the electricity grid in your street (feed-in or export).

Electricity can flow in only one direction at a time down the cable between the street and your house. Your meter has two registers. Whenever electricity is flowing from the street into your house, the import register is accumulating, costing you 29 c/kWh. When electricity is flowing from your house to the street (feed-in), the export register is accumulating, earning you 8 c/kWh (expected to drop to 6 cents or so next year).

If you got onto a premium feed-in or transitional feed-in contract several years ago, your feed-in tariff would be higher, eg 66 c or 25 c/kWh. With current low feed-in tariffs, your solar generation gives best value when consumed within the house. We wrote an article on this last year: www.ata.org.au/news/latest-solar-payback-times.
You might find our solar electricity booklet useful: shop.ata.org.au/shop/solar-electricity

And if you’re looking to do a detailed analysis, we have developed a free tool called Sunulator. Please see www.sunulator.org.au.

—Andrew Reddaway

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