A bitter cold snap brought Texas to a standstill this week, severely disrupting the power grid and leaving millions in the dark and without heat.

At least 36 people have reportedly died due to the extreme winter weather across the central and southern U.S. so far; many died from carbon monoxide poisoning after improperly using cars and generators to stay warm.

A good portion of blame can rightly be assigned to Texas electricity grid. Unlike the rest of the continental U.S., Texas intentionally operates on its own, mostly isolated network.

Other compounding factors contributed as well, which together aligned to simultaneously increase power demand and decrease power supply, with deadly consequences.

Heres a look at what went wrong.