Energy Storage Assistance
Homeowner Critical Loads & Breaker Panel Assistance
Solar with Battery Backup
When considering the addition of energy storage or a battery backup system to your solar setup, it's crucial to comprehend your home's power consumption, the wattage of your appliances, the duration they are in operation, and the total load on your service panel.
That's why Solar First conducts a site survey to gain a better understanding of your actual appliance energy usage, your lifestyle, and your expectations for a Solar with Battery System during emergency situations before customizing the design to meet your specific requirements.
Understanding Kilowatt-Hours (kWh)
A kilowatt equals 1,000 watts. 1-kilowatt hour is the amount of energy it takes to run a 1,000-watt (or 1kWh) appliance for 1 hour. kWh represents kilowatt-hour (kWh) – it's how we measure energy in households. One kilowatt-hour is the energy required to operate a 1,000-watt (or 1 kWh) appliance for one hour. Your home's meter calculates the total wattage consumed from the grid, and the duration of use, and then multiplies it by the current electric rate (e.g., FP&L Lee County Florida charges $0.12 per kWh).
When designing the solar system, it's simple to gauge your electrical consumption based on your bill and size the system accordingly. However, when sizing a battery backup system, it's more critical to understand your appliances, their wattage, and usage patterns to ensure sufficient stored energy to last through the night when solar isn't charging the batteries. It's also essential to size the solar system correctly for the rate of charging the proposed battery capacity.
Peak Energy Demand
The power company, through your meter, can monitor the peak hours of energy consumption, which are the periods of the day when you use the most energy. This is known as PEAK DEMAND, and in regions like Arizona and California, power companies charge higher rates during these peak times for individual households. It's essential to be aware of this, as it's expected to be considered in the state of Florida as well. This is where energy storage and SMART Hybrid Inverters come into play and can significantly enhance your return on investment. The inverter can be scheduled to utilize stored energy during your home's PEAK Consumption hours to avoid higher electrical rates during those times..
Main Service Panel
A panel board, also referred to as an electrical service panel, serves as the central control center for your home's power supply. It's the primary connection point to the grid. It can be located indoors with a full circuit panel to manage your home's loads, or it can be situated outside near the electrical meter, sending power to a subpanel in another part of your home.
Subpanel
An electrical subpanel is installed downstream from the main breaker panel in a home. Subpanels are often installed in locations like barns, workshops, garages, or other additions to the home. They are rated based on their capacity to safely monitor power. To select the right subpanel size, you must calculate the peak power used by devices connected to the subpanel, ensuring it does not exceed the subpanel's maximum rating.
Calculating Service Panel Wattage
Determining how much electricity your appliances and home electronics use can help you understand how much money you are spending to use them. Use the information below to estimate how much electricity an appliance is using and how much the electricity costs so you can decide whether to invest in a more energy-efficient appliance.
There are several ways to estimate how much electricity your appliances and home electronics use:
Reviewing the Energy Guide label. The label provides an estimate of the average energy consumption and cost to operate the specific model of the appliance you are using. Note that not all appliances or home electronics are required to have an Energy Guide.
Using an electricity usage monitor to get readings of how much electricity an appliance is using
Calculating annual energy consumption and costs using the formulas provided below
Installing a whole-house energy monitoring system.
In order to calculate the total wattage of the service panel you need to identify the number of watts used by every wired-in electrical device that will be powered by the subpanel. Add all wattages to determine the power consumption of these devices. For example, if you have five 100-watt light fixtures and a 500-watt wired-in electric heater used regularly in a workshop, the total power consumption is 1,000 watts. Some of these devices may be rated in terms of amps used rather than watts consumed.
Identify any tools, appliances, and other electrical devices that you will plug in and use on a regular basis in addition to those that are permanently wired into the electrical circuits. A power-consumption sticker or graphic plate is affixed to each of these devices. Tally the wattages listed on these stickers or plates. If any of them is rated in terms of amps, save the amperages for later.
Add the total wattage used by all the electrical devices. Divide the wattage by the voltage in the circuit. This answer is the amount of amps pulled by these devices. Returning to our example, if you have 1,000 watts of wired-in devices and another 1,200 watts pulled by appliances such as a microwave, toaster, and computer, the total wattage consumed at any moment in time is 2,200 watts. Divided by 120 volts in a standard household circuit, these devices consume 18.33 amps.
To the previous amp total, add any amperages from devices for which power consumption is rated in amps rather than watts. For example, a contractor-grade 7 1/4-inch circular saw typically pulls between 12 and 13 amps. A heavy-duty drill is rated between 3.2 and 5 amps, and other stationary bench tools usually fall somewhere in between. If you have a furnace and any other electrical HVAC equipment such as a hot water heater and sump pump, be sure to include these machines in your tabulations. The result is the total amperage needed for the subpanel
Some of these devices are rated in terms of peak amps, which the device draws when it is first turned on, and amps drawn under normal operation. The panel should be able to handle peak loads in order to create a margin of safety. For these devices, use the peak amps in your calculations.
Calculating Appliance Wattage
Multiply amps by volts to determine the total wattage for each circuit. For example, a 20-amp single-pole breaker multiplied by 120 volts equals 2,400 watts.
Note: To ensure safe circuit usage, do not exceed 60 percent of the circuit's wattage capacity, as per NEC standards. Divide the wattage by 120 volts to determine the number of 15-amp receptacles you can safely place on the circuit.
Electric Use Monitors
Electricity usage monitors are easy to use and can measure the electricity usage of any device that runs on 120 volts. (But it can’t be used with large appliances that use 220 volts, such as electric clothes dryers, central air conditioners, or water heaters.) You can buy electricity usage monitors at most hardware stores for around $25-$50. Before using a monitor, read the user manual.
To find out how many watts of electricity a device is using, just plug the monitor into the electrical outlet the device uses, and then plug the device into the monitor. It will display how many watts the device uses. If you want to know how many kilowatt-hours (kWh) of electricity the devices use in an hour, or a day, or longer, just leave everything set up and read the display later.
Monitors are especially useful for finding the amount of kWh used over any period of time for devices that don’t run constantly, like refrigerators. Some monitors will let you enter the amount your utility charges per kilowatt-hour and provide an estimate of how much it costs to run the device since it was plugged into the monitor.