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The same effect works in reverse though, maintaining temperature through the heat of the day is wasteful if the temperature drops before you get home. If you’re dealing with significant solar gain then running a fan before turning on the AC becomes even more efficient.

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Only if it's already cooler outside than inside the house. On a day where it's only 90 out during the day, it's not dropping to 75 until 8-9pm at the earliest.

Also can't use a fan on the west coast in the later parts of the summer when the air is full of wildfire smoke.

An example of significant solar gain would be a car sitting outside in sunlight. A surprising amount of modern architecture would work just fine as a greenhouse. Assuming a 9 hour workday it’s going to get well above ambient before you get home.

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