Emergency Power Backup
Portable Generator for Backup Power
Severe weather, power grid failures and electric utility breakdowns create reasons why the power goes out. And, it’s not long before you remember just how crucial electricity is in meeting your basic needs and comfort. More and more we are thinking ahead and planning for backup power during these failures. There are many ways to achieve backup power, and you should thoughtfully plan what’s best for your family and your home.
Installing a portable generator? Why do you need to install a generator 6, 10, etc circuit panel and not an interlock kit or back-feed the main panel?
National Electric Code (NEC)
NEC 702.4 Capacity and Rating. (B) System Capacity. The calculated load on the standby source must be in accordance with Article 220 or by a method approved by the authority having jurisdiction. (1) Manual Transfer Equipment. The optional standby power source must have adequate capacity for all equipment intended to operate at one time as determined by the user.
Is a portable generator right for you?
There are two primary methods we use for backup power: standby generators and portable generators.
Standby generators start up automatically during a power outage. They can supply power for most, if not all, of your home’s needs. The investment is greater, both in upfront costs and ongoing maintenance.
Portable generators are smaller, more versatile generators used in a variety of purposes. Plus, they're installed at a greater cost savings compared to standby generators.
They can also be used for camping, tailgating, outdoor parties, and many other events! While losing power to your home is no party, a portable generator that is properly connected to your home’s breaker box can temporarily power your essentials and some minor comforts until things are back to normal. Our suggestion? Portable generators!
How a portable generator is used for backup power to your home
To use a portable generator to power to your home’s electrical circuits in the case of an outage, you’ll need to have Staples Electric install an inlet box that connects to your home’s electrical breaker box. Your generator cord will plug-in to the portable generator at one end, and into the inlet box at the other end. This inlet box in normally connected to a generator circuit panel. In-turn, these generator panels are used multifunctionally between utility power and generator power - so once connected, there's just a few flips of a switch to have generator power through the home or connect back to utility power. As noted, code compliance dictates how a generator is connected, etc.
The installation of a transfer switch will keep your power from the utility (grid) OFF while your portable generator power is ON (and vice versa). Which, is in complete code compliance.
Load Shedding
Load shedding is turning off systems using power, such as ovens and AC systems. Residential homes are not allowed to manually load shed under generator power. The generator should be rated to carry the expected demand load of the home. Using a device to back-feed a main panel is also not NEC compliance. We see a lot of companies installing generators and NOT installing automatic controlled load shedding modules or portable generator panels that run with overloaded generating capacities. Most power utility companies supply 200 amps @ 120/240 volts to a home. A typical static generator (20 kw) has only a 100 amp breaker feeding the home / business and is required to utilize load shedding modules. Majority of these installations DO NOT have these modules.
NEC articles commenting on load shedding....
(Compliance with NEC (National Electric Code) = compliance with homeowners insurance and maintains a safe installation. Any installation not in compliance regardless of when or whom installed the system may not be covered under insurance and any accident may not be covered under insurance.)
NEC Article covering load shedding!
702.2 Definition. Optional Standby Systems. Optional standby systems are intended to supply power to public or private facilities or property where life safety doesn’t depend on the performance of the system. Optional standby systems are intended to supply on-site generated power to selected loads either automatically or manually. Note: Optional standby systems are typically installed to provide an alternate source of electric power for such facilities as industrial and commercial buildings, farms and residences, and to serve loads such as heating and refrigeration systems, data processing and communications systems, and industrial processes that, when stopped during any power outage, can cause discomfort, economic loss, serious interruption of the process, damage to the product or process, or the like.
702.4 Capacity and Rating. (B) System Capacity. The calculated load on the standby source must be in accordance with Article 220 or by a method approved by the authority having jurisdiction. (1) Manual Transfer Equipment. The optional standby power source must have adequate capacity for all equipment intended to operate at one time as determined by the user. Author’s Comment: When a manual transfer switch is used, the user of the optional standby system selects the loads to be connected to the system, which determines the system kVA/kW rating. (2) Automatic Transfer Equipment. (a) Full Load. The optional standby power source must have adequate capacity to supply the full load transferred. For a new installation, the load is determined by Article 220 or an alternate method approved by the AHJ. For existing facilities, the maximum demand data for one year or the average power demand of a 15-minute period over a minimum of 30 days can be used to size the power source [220.87].
Picture below of interlock kit. Do NOT install an interlock kit on your main panel and expect a generator to feed a home or business unless it's rated at the power utilities incoming power. If your generator doesn't provide enough wattage capacity to run your whole house, you'll need to install a generator panel or load shedding modules. If you have a smaller 5k-15k portable generator, you will install a generator 6-10+ circuit generator panel. These panels are extremely versatile and even have watt meters to show real-time load draw.
