How it's done today - (just like 50 years ago) Rolling Blackouts
When peak isn't enough, the utility needs to immediately curtail demand to prevent damage to its equipment. The only alternative to such unfortunate situations is to shut off substations and black out neighborhoods. Imagine some of the Negawatt advantages --
>Cut off HVAC in homes but leave on refrigeraters
>Turn off pool filers and electric water heaters
>Leave on VoIP communication systems
>Leave on health related appliances
>Leave on computer networks
>Turn off signage in stores but leave on cash registers
>Turn off 80% or 90% of interior lighting providing safety lighting only
>Turn off street lights but leave on traffic lights
>Leave on security systems
>Turn off charging systems
>Leave on elevators
>Turn off escalators
As you can see the command and control of utility decisions can be precise and less obtrusive to daily activity.
With common sense planning, and on a varying level of priorities, the consumers of a utility can be controlled like a Marinette puppet on a string, under a sophisticated and imaginary combination of necessity, safety, and convenience. Efficient savings of power is what Negawatt is all about.