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Add efficient inverter cooling matched to solar

When passive measures are not enough, an inverter mini-split is usually the most efficient active cooling. Cooling demand peaks with sunshine, which suits solar power well.

How

1. Size each unit from the room cooling load, not by rule of thumb, to avoid short cycling and poor dehumidification.
2. Choose variable-speed (inverter) units, which can throttle down to around 10% of capacity.
3. Schedule most cooling for solar hours and pre-cool rooms in the afternoon.
4. Plan condensate drainage and periodic deep cleaning of the indoor blower (every 1 to 3 years in PNNL guidance).
5. Add the running and start-up watts to the power design.

Do these first

• power-1

Sources

1. Ductless Mini-Split Heat Pumps. Pacific Northwest National Laboratory, Building America Solution Center, accessed 2026-11
2. Evaporative Cooling Systems. Pacific Northwest National Laboratory, Building America Solution Center, accessed 2026-11

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