PCBs were routinely used until about 25 years ago in the manufacture of a number of items, including electrical transformers.

FORBES: Surplus?

Any electrical or electronic device - including the grid's transformers - not shielded against this pulse would be, at best, taken temporarily off-line.

CENTERFORSECURITYPOLICY: EMP and you

Damage to the grid: Power surges and electrical system failure due to high loads can cause power outages and damage to BC Hydro equipment and infrastructure, including the premature failure of distribution transformers.

FORBES: Electricity Theft: A Bigger Issue Than You Think