Is Spotcheck a copy of any retailer's controller?

No. Spotcheck doesn't reverse-engineer any retailer's dispatch software. It solves its own version of the same problem — when to charge, when to discharge, when to import, when to export — against the same wholesale prices.

Is the savings number a guarantee?

No. Real homes have network rules and edge-case behaviour the simulation doesn't model. Treat the figure as the best honest estimate, not a promise.

Will Spotcheck always recommend switching?

No. Sometimes the answer is 'don't switch' — that's the whole reason this tool exists.

How long does an estimate take?

Simulating a full year of 5-minute prices typically takes a couple of minutes. Spotcheck submits the job asynchronously and streams progress to your browser.

Does Spotcheck cover all of Australia?

Spotcheck works for postcodes inside the National Electricity Market (NEM). Western Australia and the Northern Territory are out of scope until the relevant wholesale data is ingested.

How Spotcheck works

When you ask whether a spot-pricing plan is worth it, Spotcheck plays out a full year for your home — every five minutes — using real wholesale prices and a typical solar profile for your postcode. The savings number is the difference between that and what a flat-rate plan would have cost you.

That number is only useful if our simulation behaves like a real home would on the day. Here’s how we know it does.

A real home vs our simulation

Here’s data from what a real home controller does, compared to our simulation on the same day. The household: 13.3 kW of solar with a 13.5 kWh Powerwall 3 in Whyalla, SA. We compared 90 days of real five-minute data against what our simulation said the same home would do, with the same prices.

Pattern match

96%

across the comparison window

How closely the simulation's hour-by-hour pattern of importing and exporting tracks the real home's.

Bill match

98%

$2 off per month

Real bill $10/mo vs simulated $11/mo (negative = export-positive).

Battery activity, day shown

2.2×

full-battery cycles

Picked from the busiest 74 of 82 days, then chosen for closest match.

Representative dayMonday 23 March 2026

Partly cloudy↑ 32.8°C↓ 16.5°C0.0 mm rain

Top half: home consumption. Bottom half: feed-in to the grid. The shaded backdrop on each side shows what the battery did and the green line is its state of charge — real on the left (from the home’s telemetry export), simulated on the right (what the simulation decided). The shaded vertical band is the 4–7pm peak.

Real homefrom interval data

Home Feed in Battery Charge

12am6amnoon6pm12am

Simulatedour simulation, same prices

Home Feed in Battery Charge

12am6amnoon6pm12am

Where the data comes from

Wholesale spot prices. 5-minute regional reference prices published by the Australian Energy Market Operator (AEMO). Updated continuously through the day.
Typical solar profile. A typical-meteorological-year (TMY) per-kW solar series for your postcode, from PVGIS (the European Commission’s Photovoltaic Geographical Information System), which models long-run solar irradiance from satellite data.
Regional rooftop PV + predispatch.Half-hourly regional rooftop PV measurements and AEMO’s 30-minute predispatch forecasts, used for sensitivity analysis around the headline number.

What this isn’t

It isn’t a copy of any retailer’s controller. We don’t reverse-engineer any spot-passthrough retailer’s software. We solve our own version of the same problem — when to charge, when to discharge, when to import, when to export — against the same wholesale prices.
It isn’t a guarantee.Real homes have network rules and edge-case behaviour our simulation doesn’t model. Treat the savings figure as our best honest estimate, not a promise.
It isn’t a sales pitch.Sometimes the answer is “don’t switch.” That’s the whole reason this tool exists.