Not every generator is large enough to power everything in your home at once. Even if it is, there are moments when multiple high-draw appliances starting simultaneously can overload the generator and trigger a shutdown. Load management systems solve this problem by intelligently controlling which circuits receive power and when, ensuring your generator provides maximum coverage without overloading. Understanding how load management works helps you get whole-home-like coverage from a smaller, more affordable generator.
What Is Load Management?
Load management is a system that monitors the total electrical demand on your generator and automatically controls which circuits are active based on available capacity. When the generator is lightly loaded, all managed circuits receive power. When the load approaches the generator's maximum capacity, the system temporarily shuts off lower-priority circuits to make room for higher-priority ones.
Think of it like a traffic light system for your electrical circuits. Essential circuits like refrigeration, HVAC, and lighting always have a green light. Lower-priority circuits like the electric dryer, water heater, or pool pump get a green light when capacity is available and a red light when the generator is running close to its limits.
The process is entirely automatic. You do not need to flip switches, unplug appliances, or make decisions about what to turn off. The load management system makes those decisions in real time, hundreds of times per second, based on actual generator load readings.
How Load Shedding Works
Load shedding is the specific mechanism by which a load management system removes circuits from the generator when capacity is strained. Here is a step-by-step look at what happens during a typical load shedding event:
Step 1: Load Monitoring
The load management module continuously monitors the generator's output current. It knows exactly how many amps the generator is producing at any given moment and how close that is to the generator's rated capacity.
Step 2: Threshold Detection
When the total load reaches a preset threshold, typically 80 to 90 percent of the generator's rated capacity, the system prepares to shed load. This threshold provides a buffer so the system acts before the generator actually overloads.
Step 3: Priority-Based Shedding
The system sheds circuits in reverse priority order: the lowest-priority circuits go first. For example, if your air conditioner compressor starts and pushes the load above the threshold, the system might temporarily disconnect the electric water heater and the clothes dryer to free up capacity for the AC.
Step 4: Load Restoration
Once the demanding load stabilizes and the total demand drops below the threshold, the system reconnects the shed circuits. The water heater and dryer come back online. This entire cycle happens automatically and typically takes only a few seconds to a few minutes.
Priority Circuits: What Should Get Power First?
When setting up a load management system, circuits are assigned priority levels. The highest-priority circuits always receive power. Lower-priority circuits receive power when capacity is available and are the first to be disconnected when capacity is constrained. Here is how most Aiken homeowners prioritize their circuits:
Tier 1: Always On (Highest Priority)
- Refrigerator and freezer: Food spoilage starts within hours without power. These circuits draw relatively little power (400-800 watts each) and should never be shed
- HVAC blower and controls: The blower fan and thermostat controls need constant power for heating and cooling to function. The compressor may be managed separately as a large load
- Essential lighting: Kitchen, hallways, and bathrooms need light for safety. LED lighting draws very little power
- Medical equipment: CPAP machines, oxygen concentrators, and other medical devices are life-safety items that must always have power
- Security system: Alarm systems and cameras should remain active during outages
- Well pump: For homes on well water, the pump provides water for drinking, cooking, and sanitation
- Sump pump: If you have a sump pump, it must run during storms to prevent flooding
- Internet and communications: WiFi router, modem, and phone chargers draw minimal power but provide essential connectivity
Tier 2: Managed (Medium Priority)
- HVAC compressor: The air conditioner or heat pump compressor is typically the single largest load in the home (3,000-6,000 watts). It is managed rather than always-on because its starting surge can momentarily spike the load. The load management system ensures it can start without overloading the generator by briefly shedding other loads during startup
- Electric water heater: Water heaters draw 4,000-5,500 watts but do not need to run continuously. They can be shed for 30 minutes to an hour without noticeably affecting hot water availability
- Kitchen range/oven: If you have an electric range, it can draw 4,000-8,000 watts. It can be managed so it operates when HVAC demand is low
Tier 3: Non-Essential (Lowest Priority)
- Electric clothes dryer: 5,000-5,500 watts. Laundry can wait. First to be shed
- Pool pump: Can be off for days without issue
- Electric vehicle charger: EV charging can wait until utility power returns or until overnight when HVAC demand drops
- Spare bedroom circuits: Rooms not in active use do not need power during an outage
- Decorative lighting, outdoor lights: Non-essential during an outage
Managed Whole-Home vs Full-Coverage Whole-Home
This is where load management creates a compelling value proposition. There are two approaches to powering your entire home with a generator:
Full-Coverage Whole-Home
A full-coverage system uses a generator large enough to power everything in your home simultaneously, including worst-case scenarios like the AC, water heater, dryer, and range all running at once. For a typical 2,500 square foot Aiken home, this requires a 22-26kW generator, costing $10,000 to $15,000 installed.
Managed Whole-Home
A managed system uses a smaller generator paired with a load management system that prevents simultaneous operation of the largest loads. The generator still powers every circuit in your home, but not all at the same time. The load management system ensures the total demand never exceeds the generator's capacity by cycling large loads on and off as needed.
For the same 2,500 square foot home, a managed system might use a 14-18kW generator with load management, costing $7,000 to $11,000 installed. You save $3,000 to $5,000 on equipment while still having access to every circuit in your home.
The Trade-Off
The trade-off with managed whole-home is that you may occasionally experience brief interruptions on lower-priority circuits. Your water heater may not heat while the AC is running. Your dryer may pause for a few minutes when the AC compressor kicks on. For most homeowners, these brief interruptions are invisible or barely noticeable, and the significant cost savings make managed whole-home the better value.
Load Management Systems by Brand
Generac Smart Management Modules (SMMs)
Generac's load management system uses individual Smart Management Modules installed on managed circuits in your electrical panel. Each SMM monitors and controls one or two circuits. The modules communicate with the generator's controller to coordinate load shedding. Generac SMMs can manage up to eight circuits and are compatible with most Generac air-cooled generators.
Kohler Load Control Module
Kohler offers integrated load management through their load control modules, which work with Kohler generators and their RXT transfer switches. The system provides similar functionality to Generac's SMMs with priority-based load shedding and automatic restoration.
Briggs & Stratton Symphony II
Briggs & Stratton's Symphony II power management system is their load management solution. It manages up to four large loads and is designed to maximize the coverage of their mid-range generators.
Planning Your Circuit Priorities
When we install a load management system, we work with you to establish the right priorities for your household. Here are the questions we walk through:
- What absolutely cannot lose power? Medical equipment, sump pumps, and security systems are always in the highest tier
- How important is continuous air conditioning? In an Aiken summer, most homeowners prioritize AC highly. In milder weather, it can be managed more aggressively
- Do you work from home? Home office circuits may need to be in the always-on tier
- Do you have a well pump? Well pumps are essential for homes not on municipal water
- What large loads can you live without temporarily? The dryer, oven, and water heater are the most common candidates for load shedding
- How long are your typical outages? For short outages, aggressive load management is fine. For multi-day outages, you may want more comfort and less shedding
Load management can be adjusted after installation. If you find that shedding the water heater is more disruptive than expected, we can change the priorities. The system is flexible and can be tuned to your household's actual experience during outages.
Unity Power & Light installs generator load management systems throughout Aiken County. Whether you want to maximize coverage from a smaller generator or add intelligent load control to an existing system, we can design and install the right solution for your home. Call us at (803) 220-4491 for a free consultation.