Shading the condenser unit keeps it cooler and increases it’s efficiency and helps keeps my electricity costs down. The sail is high enough and mesh like so that it doesn’t trap the hot air. In fact it creates a slight wind tunnel effect. The shade it provides lasts during the hottest part of the day and a tree helpfully blocks the sun for the remainder. The unit is never in full sun this way. Keeping the weeds and other debris away from the unit so that it gets good airflow and cleaning the condenser every year also help with the units efficiency.
If your unit is a heat pump, are you then paying for that savings in the winter when it doesn’t benefit from any solar warmth to help heat your house? If so, I wonder if it is a relatively balanced outcome or if one of the seasons has a bigger impact. I imagine it depends in part on which season is more extreme in your area.
I would think so. Another factor would be dropping leaves in the fall and winter so less shade, a good thing, in this case.