Swell Sport · Practical guide

Sauna electricity tariffs: flat rate versus time of use

Compare electricity plans against the whole household schedule, not the cheapest advertised sauna hour. Use your bill and actual timing to build the comparison.

Swell Cedar Cube 2 in a home setting.

Copy the complete offer

Give each plan a column. Enter daily supply charges, usage bands, applicable days, seasonal dates, demand terms, export credits, discounts and offer expiry. Preserve whether prices include GST. Single-rate tariffs price grid usage consistently across the day; time-of-use rates depend on the period. Weekend and seasonal rules may differ. ^[1]

Write realistic heating windows before looking for the cheapest one. The household must still be able to carry out required checks and enjoy the sauna without rushing. An attractive tariff window does not create permission for unattended operation or for changing the approved controller arrangement.

A usage-only worked comparison

Assume 20 kWh of imported sauna energy in a hypothetical comparison period. At an illustrative flat $0.32/kWh, usage costs $6.40. Under a different illustrative plan, 8 kWh at $0.48/kWh and 12 kWh at $0.20/kWh cost $3.84 + $2.40 = $6.24. The sauna usage difference is only $0.16.

These are worksheet assumptions, not current retailer quotes or promised savings. Neither figure includes the rest of the home. A higher supply charge or different export credit could outweigh the difference. Government guidance distinguishes fixed supply charges from variable charges, so keep them in separate rows. ^[2]

Split a cycle at tariff boundaries

Do not price the entire cycle at its starting rate. Allocate measured imported energy to each applicable period. Where a monitoring interval straddles a price change and the allocation is uncertain, label the split estimated. Confirm the retailer’s clock and daylight-saving treatment rather than assuming its timestamps match the sauna controller.

Include warm-up and any manufacturer-directed powered finishing stage. These periods are for energy accounting, not bathing advice. A person does not need to stay inside until a billing interval ends, and the cabin does not need to remain enabled merely because the next band is cheaper.

Compare the household before switching

Recalculate other imported household energy over identical dates and add fixed and demand components where applicable. For a solar household, also compare export credits. The Government recommends considering fixed and variable charges together with feed-in tariffs, not choosing a plan on a single eye-catching rate. ^[1]

Use two schedules if flexibility is uncertain: the routine the household normally manages and a less convenient week. If the proposed plan only wins under perfect timing, record that limitation. Save the dated offer and any written explanation of unclear terms, then check the first bill against the assumptions. Do not confuse an annual plan comparison with a guarantee about the price of every future sauna cycle.