Best way to fit a bypass for a whole house pump

[Chalked]

When fitting a whole house pump with break tank, I tee on the water main after the pump ( with a stop tap and double check valve). This enables the customer to still get water if there is a power cut.
Does anyone know of a normally closed valve, that will open on power failure, so this can be done automatically?
cheers.

 

[ShaunCorbs]

The only way I could think of it is a normally open solenoid valve (closed when power is on) but the do get warm that's the only problem I could see