HB 3493 prohibits municipalities from regulating the installation or inspection of residential energy backup systems. The bill defines a residential energy backup system as one that provides no more than 50 kilowatts of electricity or has a storage capacity of no more than 100 kilowatt-hours. The bill amends the Local Government Code to prevent cities from modifying the National Electrical Code in a way that would regulate these backup systems. It also prevents cities from enforcing ordinances or rules that limit their installation or inspection. The law applies only to installations or inspections initiated on or after September 1, 2025​.