A whole house surge protector provides protection against large current spikes that occasionally occur during power outages that destroy electronic devices in your house.  We have seen power surges take out furnace controllers, irrigation controllers, circuit breakers in your panel and unprotected equipment in the house.  These devices are installed in your circuit breaker panel to protect everything connected to the panel. Starting 2020 all new houses in Washington state are equipped with a surge protector.  These are a great add-on if you are already getting electrical work done at your house.

If you have a surge protector, you should check after power outages that it hasn't been triggered.  These devices can be destroyed by large enough current surges.