Why it matters to you
If the outdoor unit is damaged by storm debris or ice, EM heat can keep a Greater Houston home warm until it is repaired. Because it runs entirely on resistance heat, leaving it on longer than needed uses much more electricity than normal heat pump operation.
Practical guidance
Switch to EM heat only when the outdoor unit is clearly not working or has been damaged, and schedule a repair rather than living on it. If any part of the system sat in floodwater, keep the whole system off and have a licensed technician inspect it before running it again.