If you have an ‘Anytime’ electricity tariff where the charges are the same all day, then it does not matter, except that you will generally get the best result with daytime running as there is less cooling during the day. Heat-Pumps are also generally more efficient during warm daytime than cold nights.
If you have
a ‘Time-Of-Use’ tariff and a solar heater which must run during sunny times,
then starting at about 10 a.m. and operating until when peak charges apply
(usually 1 p.m. or 2 p.m.) is a good choice. This keeps your operating times in the shoulder periods and out of the
expensive peak charge periods that exist on weekdays.
If you need a ‘top-up,’ you can override the system and go later into the afternoon when you wish. You can also have different operating times on weekends when there are no peak charges, compared with weekdays, when there are. With Pooled Energy’s optional Intelligent Solar Power Management, the system will also respond to weather and forecast.
If you have a Time-Of-Use tariff and a Heat Pumps, it is almost always less expensive to run during the night off-peak periods, provided that you have a pool cover. While the amount of heat available from the air is reduced at night, this is usually more than offset by the lower electricity charges in most cases, down to air temperatures of about 0-10 degrees C depending on the type and brand of heat pump. For operation in lower air temperatures, please contact us with details of your heat pump for a recommendation. See also the discussion in the FAQ Sizing a Heater and Other Considerations.
With Time-Of-Use and Gas Heaters, low cost operation is best done off-peak due to the electricity usage of the pump, but it really depends on when you want the pool warmer. Gas usage prices do not vary based on the time of day the gas is used but pools do cool differently day and night. Try both and see which is better for your pool.
If you have gas heating and Net Metered Solar PV panels which only generate electricity during the day, then the best time will depend on system capacities and the type of heater. Please discuss with us. Please note that the more energy efficient approach to heating a pool by using solar thermal panels, gas or heat pump systems. Deploying solar PV to operate a Heat Pump is usually not efficient, unless you have a large number of panels.