Home battery installation process: What to expect

If you’ve decided to have a home battery installed, you’ve made the right choice. A home battery system provides your family with security and comfort during a power outage. Home batteries come with a host of advantages, from their clean, quiet, and painless energy distribution to their cost-effective techniques. More and more homeowners are installing home batteries such as Tesla’s Powerwall to keep their home running smoothly under any circumstance. For many homeowners, however, the home battery installation process remains a mystery.

Unless you’re an electrician or electrical engineer, you probably don’t understand how the home battery system will be made a part of your home’s circuits. You may think that since an electrician will be the one who installs the battery, you don’t need to understand the home battery installation process. However, having a basic understanding of what to expect before the electrician arrives will give you more insight and control over important details such as where you put the home battery and how it is wired into your home’s circuits.

You’ll also want to understand your home’s energy consumption before you purchase and install your home battery system. How much energy you and your family consume will impact what kind of home battery you need and how long you will be able to use it for during a power outage. To calculate your household’s energy consumption, use AlltimePower’s free backup power calculator.

Home battery installation location

Before the electrician comes to install your new home battery system, you’ll want to have a good idea of where to mount the battery. If you received a cost estimate for the home battery installation, you may have already discussed the location with the installer. Either way, the best location to install the battery is usually close to your main residential panel. This will allow the electrician to more easily wire the battery to your house’s circuits. Depending on the size and brand of the battery system and your personal preferences, you can have the battery system mounted on the wall or the floor.

Make sure you think through where you have the battery installed because it won’t be easy to change later. If you are planning on redecorating or repainting your home, keep in mind what changes you plan to make. The home battery system should not interfere with the beauty or usefulness of your home. Also keep in mind how you want the home to look if you ever decide to sell it. The home battery system will certainly raise the value of your home, but make sure the added value is not diminished by poor placement.

Depending on where you live, there may be codes or regulations regarding where the home battery can be placed. For instance, some regulations might require certain clearances or even an enclosure to protect the safety of the homeowner. If you are unsure about local codes, contact your installer. He will likely be aware of any local regulations regarding home battery installation.

Home battery installation with an existing solar system

Some homeowners choose to add a home battery to their existing solar system. This is a smart choice; a home battery system collects excess solar energy and releases it during times when the solar panels are not producing enough energy to sustain the home’s electrical appliances. This allows homeowners to save money and have more control over their energy consumption. They also tend to provide more lasting power during a power outage than solar energy or stored energy from the grid alone.

If you are buying your battery system as an add-on to an existing solar system, then you will have a couple of choices for how your system gets configured. If you choose a DC coupled system, your installer may need to replace your existing solar inverter with a “storage-ready” inverter. Alternately, you might choose an AC coupled system in which a second inverter is installed to service the battery. If you don’t have solar, you will install an AC coupled battery and inverter.

Main circuit panel

Whether AC or DC coupled, the inverter for your battery system will need to be connected to your main circuit panel. The main circuit panel receives power from the electrical grid and distributes it through your home’s circuits to various electrical appliances. The battery system stores power from the main circuit panel to distribute during an outage. After installing a battery, only some larger loads will remain connected to the main circuit panel. The battery system will act as a middleman for any other loads.

Transfer switch

A transfer switch is what transfers power from the electrical grid to the home battery system during an outage. When a power outage occurs, the transfer switch senses that the power has been disrupted and cuts off power from the electrical grid. It then starts supplying the home’s electrical circuits with stored power from the home battery. Once the power outage ends, the transfer switch restores power from the electrical grid.

In addition to ensuring your home’s appliances receive power during an outage, a transfer switch also prevents home batteries from injecting energy into the grid when power is out and repairs are being made. The electrician generally installs a transfer switch when he comes to install your home battery system. Be sure to discuss the specifics of the transfer switch with your installer before installation.

Critical load panel

Home battery installers often recommend adding a critical load panel to limit which loads are powered during an outage. Limiting loads ensures that power is reserved for the most critical loads during an outage. For example, if an air conditioning unit requires a particularly high current load to start up, a critical load panel would conserve energy to ensure the unit receives enough amperage to start up.

Installing a critical load panel will add several hundred dollars to the installation process, so it is a good idea to question whether it is really necessary. If you want to ensure that certain higher-amperage appliances in your home, such as the air conditioning or heating, function, you may need a critical load panel. Otherwise, a home battery will still function during an outage without one.

Another way to conserve energy during an outage is to limit which appliances you and your family use. For instance, you may want to wait to use the washing machine or dishwasher or limit how long you shower to make sure more important appliances, such as air conditioning or heating, work for the entire duration of the outage. It is especially important to be prudent about your energy usage if you expect the outage to last longer than a few hours. It is also possible to turn unnecessary loads off at the main circuit panel. If you are unsure how to do this safely, ask your installer or another qualified electrician.

Wiring during the home battery installation process

During the home battery installation process, the installer will need to wire the battery, inverter, transfer switch, and, if you choose to install one, the critical load panel to your home’s main circuit panel and your home’s circuits. This involves running new wires to each new device. The battery is connected to the inverter, and the inverter is connected to the main circuit and, if present, the critical load panel. The transfer switch is installed to sit between the electrical grid connection and the main circuit panel or critical load panel.

The installer will need to shut off power to your home for the duration of the wiring process. Unless you are a certified electrician, do not attempt to wire the home yourself, as this may result in serious bodily harm or permanent damage to your home’s appliances. The wiring process is complex, but once the electrician has fully installed your home battery system, programmed the battery, and tested the system, you and your family will be ready for the next power outage.

Programming your new home battery system

Once the installer has finished wiring the home battery system, he will conduct the initial programming for the battery. Programming represents another advantage of home battery systems over other sources of backup power, such as fuel-powered generators. Home batteries allow you to program instructions such as what time of day you want the battery to charge and discharge. This will let you take advantage of times when utility costs in your area are lower, thus saving you money in the long run.

You will also likely want to set your home battery system to automatically take over powering your home if the grid voltage disappears. The programming works in conjunction with the transfer switch to let the home battery function as backup power during an outage. Today, thanks to incredible technological innovations, most systems allow you to change the programming yourself using a mobile app.

How long will the home battery installation process take?

How long it takes the installer to wire and program your new home battery system depends on a number of factors, including the complexity of your home’s wiring, what kind of home battery system you are installing, and whether or not you choose to install a critical load panel. On average, it will take about 4 to 8 hours to install, so it should take no longer than a day or possibly two.

Remember, the electrician will need to shut off power in your home while working, so you and your family should prepare to spend a few hours without electricity. Once the system is installed and programmed, though, you’ll be prepared to keep the power on during the next unexpected power outage.

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