Graphic of Grid Connected Batteries and Solar Setups

Understanding Grid-Tie Battery Backup Solar Energy

A grid-tie battery backup system is the perfect union between a connection to civilization and suburban self-reliance.

Why is this such an optimal setup for your solar energy system? Why do so many people choose this option? Before we get into why it’s so great, let’s talk about what grid-tie battery backup even means.

What is a grid-tie battery backup system?

It’s a simple combo of two different things. A connection between your PV panels and the local power grid, as well as battery energy storage at your home.

Electrical Power Grid Tied to Home Residential Solar Panels

Connection to the grid allows you to take advantage of net metering. This allows panels to work well despite their limitations at night and in winter.

Batteries allow you to be protected during outages and will enable you to save money in areas that have those pesky time-of-use rates.

But what’s the alternative?

Grid-Tie vs. Off-Grid

Off-grid power is one of the main alternatives to a grid-tied system. Off-grid is exactly what it sounds like, a separation from the power grid. It means you are totally in control, but also totally responsible for your power.

Off-grid may sound nice when you think about being completely grid-independent. As great as it may seem to leave society’s ailing power grid behind once and for all, there are some benefits to maintaining a connection.

Solar panels rock, but they have one crippling limitation…

Darkness.

At night they don’t produce power. In the winters they produce a lot less power than in the summer. If you had a lot of batteries you could potentially charge them up enough during the day to power your home all through the night.

However, no amount of batteries would be effective enough to power your home in the winter with leftover energy from summer. This isn’t even taking into account overcast skies that can last for days at a time.

This is where a grid connection comes in handy. The local power grid can act as a safeguard, and as a virtual battery. This totally eliminates the problem of darkness. The way this works is through net metering which we’ll talk about later.

Battery Backup

Large batteries serve as backup power for your home. You can start with one, and then keep adding.

In most cases, this backup power will only cover the most essential power draws on a home. Batteries can often power the critical loads of a home. Things like the lights and the fridge, or even essential medical equipment. 

Battery Backup for the Grid Tie Residential Solar Operation

While a battery backup isn’t necessary, they are extremely helpful to have. Most people don’t realize that in the event of a power outage, solar panels and inverters are required to shut off power production.

The reason for this is that as soon as a power outage occurs, the utility company is going to be working on fixing it. The linemen that work on these outages are supposed to be working on a dead grid at that point in time. If the panels on your home are still producing, this exposes them to the risk of electric shock at high voltage.

A battery allows you to use stored power. When a power outage occurs you’ll be back up in milliseconds. Battery technology has become more desirable as the number of power outages has continued to rise.

Video of Family with their Grid-Tie Battery Backup System

Is a battery backup more expensive?

Most likely, yes. It will cost more upfront to add a battery to your system. That doesn’t mean that it will be cost-prohibitive. That also doesn’t mean it won’t be worth it.

The total cost of a solar energy system depends on many factors. The number of panels, the complexity of your roof, the market rate of panels, if your home needs a new roof, and any other bells and whistles you try to get.

To know if batteries are worth it for your home and family, you’ll have to get a specific quote that takes into account all of these different variables. 

Can you add batteries after the installation of a grid-tied solar energy system?

Batteries can be added after an installation. You might want to do this if the solar energy system of your dreams was a bit out of budget at first. Maybe you only got the panels, or maybe you only got one battery. 

If you have the right kind of inverter you can keep adding batteries as need to your system.

Should I install a grid-tie battery backup system myself?

Some people want to just purchase the equipment and install the panels themselves. For some, this works out well. Especially those with prior experience with electronics, solar, roofing, and/or construction.

We’re obviously biased towards having professionals install your solar panels, and batteries for you. For argument’s sake, here are some of the benefits and drawbacks of a DIY solar installation.

Pros of DIY solar installation

  • You won’t have to pay someone else to install the panels and electronics. You can save on installation costs, although you will have to make up for it with your own time.
  • There are websites dedicated to helping you find all the equipment you need. They help you pick inverters, batteries, panels, and more.
  • You get control over choosing each component of your system. You get to configure it in the way that you want, assuming that it is up to code.
  • You’ll get to learn a lot more about your solar energy system as you figure out the process.
Pros and Cons of DIY Solar Installation for Grid-Tie Battery Backup

Cons of DIY solar installation

  • A lot of manufacturer warranties are based on a licensed installer doing the work. There’s a high risk of not qualifying for these product warranties during a DIY installation.
  • Installers almost always offer a workmanship warranty. This protects homeowners from improper installations by holding the company accountable for the errors they may have made.
  • It will likely be your first, and last time installing solar panels on your own home. It’s really hard to get anything right the first time, especially something as complex as solar panels integrated with the grid, and batteries and your home. We on the other hand have installed over 8,500 solar energy systems.
  • There’s a lot of paperwork in solar. We would take care of almost all of that for you. From system designs and electrical wiring diagrams to city/state permits and NABCEP-certified inspections, you’ll be on the hook for all of it.

Whatever choice you make, we're here to help

There are many other reasons why calling a professional installer is often the best option. Installers have made investments into safety equipment like fall arresting harnesses, and NABCEP safety training for installers and system designers. Installers like us have a team of designers, engineers, installers, electricians, and project managers that handle every part of the process.

Choosing a good installer can sometimes feel like a daunting task. We made a simple guide to choosing a good installer. We even created a printable checklist of questions to ask before you commit to a solar installer. Check out the solar installer selection guide, or reach out to us!

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