Lessons In This Module
What You’ll Learn
In this module, we’ll give you all the information you need to know when considering battery backup as an energy security solution. If you already have battery backup, sweet–congrats! You’ll hopefully find some new tips and helpful resources on this page.
If you’re more of a video person, we gotcha covered! We have a video attached to each lesson below. Happy viewing!
Lesson 00
How Does Solar + Battery Storage Work?
To begin, here’s a quick refresher on how battery backup works with solar.
Solar plus battery storage provides a backup energy solution for your home during power outages and blackouts. A battery, like a Tesla Powerwall, is paired with a solar system to store excess energy generated by the panels instead of sending it back out to the grid.
How does it work? Solar panels make electricity from the sun, which flows down through an inverter and then into the Powerwall, which will supply power to the home during a power outage.
Check out our Tesla Powerwall Guide for an overview of its technology and features, click here to check it out →
Lesson 01
How to Get Solar Panels to Work During a Power Outage?
How do solar panels work during a grid outage?
Will solar panels even work during a power outage (also referred to as a grid outage or blackout)? A common misconception is that solar panels will continue to work and provide your home with power during a blackout, but solar panels do not work during a power outage.
Let’s talk about why that is, and how you CAN get solar panels to work when the power is out.
For our folks who prefer video:
Solar panels don’t work when the power is out. Brandon is here to explain why and HOW you can change that!
Why don’t solar panels work when the power is out?
The reason your solar panels do not work during a power outage is that most solar panels today are tied into our electric grid, meaning that if they were to be producing power during an outage, they would potentially send live power back to the grid.
National Electric Code says that anything that sends power into the grid has to be shut down during an outage. Your solar panels are required to be shut down to protect the linemen working on the grid (p.s. lots of love to our linemen out there).
Common questions
Can solar panels be turned off?
Your solar inverter will do this shutdown for you automatically, but again, it is dictated by National Electric Code. You will not need to worry about a thing.
Now, to the question we’ve all been waiting for…
How do you get your solar panels to work during a power outage?
With home battery backup! Solar batteries essentially act as a mini-grid for your home, allowing you to continue to reap the benefits of the energy being produced on your roof by solar panels.
During an outage, the panels can continue to send power to your battery. The battery can then feed the power that you need into your home. It’s essentially how an off-grid system works all the time with solar charging your batteries and then your batteries providing the power into your home.
So with a home battery, your panels can continue to work during an outage. And with today’s batteries like the Tesla Powerwall, amongst others, you have wonderful access to energy monitoring. This allows you to see how much power is left in your battery during an outage and even change a few usage patterns – turn some lights off, don’t run the stove right now – to make sure that your battery and your solar can continue to keep your home going until the grid is back on.
More Resources about Tesla Powerwall During Power Outages
What does battery monitoring look like for the Tesla Powerwall | Video →
An insider’s look at the functionality and daily use of Tesla’s App for monitoring your Solar + Powerwall.
Prepping for a storm with Tesla Powerwall in North Carolina | Blog →
Whether you’re prepping for a winter snowstorm or a hurricane, Graham will walk you through what you need to know and how to keep track of the power consumed by your solar battery.
What do you really get from a Tesla Powerwall | Jump to Lesson 3 →
Skip to where we dive into topics like how many Powerwalls do you need? How long does a Powerewall keep your home running during a power outage? and more!
Lesson 02
How Long Do Solar Batteries Last When the Power Goes Out?
How long can a solar battery power a house during a power outage? If you’ve ever tried to Google this question to get an answer, the information you probably found was either way too simple or way too complicated. Instead of either of those, we want to give you a handful of things to pay attention to when trying to figure out how long your battery backup will last when the grid is down.
When getting a solar battery, you should know how long it will last during an outage. Brandon is back to walk you through what you need to know about how long your battery will last.
What are your energy needs?
How will you use energy when the power goes out? Think about your answer. If you’re trying to binge all of White Lotus while cooking chili and heating your home to 80 degrees, we won’t judge (well at least not the White Lotus and chili part)! Consuming energy that way means you’ll be shrinking down how long your batteries are going to last while the power is out. If you have high energy needs, you’ll have a similar scenario.
If you are a lower energy usage person or you’re extremely conscious of your home’s energy usage (especially when the power goes out) then you should expect your solar batteries to power your home longer then the grid is down.
Whichever bucket you fit into, there’s a product now called a SPAN Smart Panel that can help in both of those scenarios.
How can you maximize your battery backup?
A SPAN Smart Panel is truly a game-changer for solar + battery backup – it’s simple and you can extend the life of your batteries by actually changing the way your home is using energy when the power is out. You’re able to do this in real-time and on demand through the app.
We have a whole blog dedicated to how a Smart Panel can help maximize your battery backup and whether it is the right solution for you. Check it out →
Getting the right solution for your home
Once you understand what your energy needs are and how conscious you want to be with energy during an outage, the rest is pretty simple. Our solar designers work their magic to make sure that you have the right number of batteries to support those energy needs. To keep your home power up to snuff, our solar designers will also make sure you have an appropriately sized solar system that can not only power your home year-round but will also recharge those solar batteries to ensure they last even longer during an outage.
And of course, all of this is dependent on the sun coming out to recharge those batteries during an outage. But the great news is that the outages we have in North Carolina are mostly from storms – either hurricanes or winter storms, which are often quick and followed by days of sunshine to give you that ability to recharge should the outage be prolonged.
How long will a solar battery last during an outage?
There isn’t a simple answer for everyone. But since you made it this far in the blog, we’ll give you at least one simple answer, and that is – from full capacity, most solar battery storage systems will last about 24 hours if they’re not recharged. But when you pair them with solar power and that sun is out recharging those batteries, you really can get an infinite backup source for your home.
Keep reading to Lesson 3 to learn about how many batteries might be right for your home!
Lesson 03
What Do You Get Out of a Tesla Powerwall When the Power Goes Out?
What you get during a power outage from your Tesla Powerwall is dependent on what you want to be backed up and how many Powerwalls you need to make that happen.
Interested in a Tesla Powerwall but not sure what you will really get from it? Brandon walks you through how 1, 2, 3, or more Powerwalls will give you peace of mind during grid outages.
Each home is so unique with different energy needs, so as we explore this with homeowners we typically go through a checklist with you. Let’s jump into some general items on that checklist:
How many Tesla Powerwalls does your home need?
When we think through this question, we’re really asking ourselves ‘what amount of amperage is a homeowner looking to backup with a battery,’ a.k.a. What kind of things does a homeowner want to turn on and use when the power is out?
Partial Home Backup
One Powerwall
What we’re talking about here is people that are just looking for a few core items to stay on during a power outage. With a single Powerwall, you can keep on your lights, most of your outlets, you can run some of your small appliances, you can even keep your Wi-Fi router on, and power your refrigerator and freezer.
If you want much more than that, you’re going to need to bump up to a Whole Home Backup solution with either two or three Powerwalls.
Whole Home Backup
Two Powerwalls
With two Powerwalls, you keep everything listed for a single Powerwall, but now you also can add things like an air conditioning system, your electric stove, an electric dryer, and even a small 30 amp EV charger.
Whole Home Backup
Three Powerwalls
If you have larger energy needs, then you’ll want to consider bumping it up to three or more Powerwalls. Three solar batteries will cover everything we talked about up until this point + loads like an electric heat pump or 50 amp EV charger.
To summarize, here is what you’ll generally get out of each scenario when the power is out:
1 Powerwall
- Lights
- Wall Outlets
- Some Small Appliances
- Wi-Fi Router
- Refrigerator, Freezer
2 Powerwalls
- Lights
- Wall Outlets
- Some Small Appliances
- Wi-Fi Router
- Refrigerator, Freezer
- A/C System
- Electric Stove
- Electric Dryer
- 30 Amp EV Charger
3+ Powerwalls
- Lights
- Wall Outlets
- Some Small Appliances
- Wi-Fi Router
- Refrigerator, Freezer
- A/C System
- Electric Stove
- Electric Dryer
- 30 Amp EV Charger
-
Larger Loads
(Ex: Electric Heat Pump, 50 Amp EV Charger)
So, no matter which option you choose, each battery solution provides a different layer of backup protection when the power goes out.
Extending Your Battery Storage
One of the things we’re excited about now is a new product called a SPAN Smart Panel – a smart electric panel that, when paired with batteries, gives you even more flexibility when the grid goes down. You’ll be able to decide, in real-time, what you want to run or turn off in your home and see how it extends the life of your battery while the power is out.
Dive into our SPAN Panel 101 Guide to learn more and see if SPAN is right for you →
What do you get from a Tesla Powerwall when the power goes out?
Now, back to the original question. While each home is different and unique, what you get across the board with a Tesla Powerwall battery is peace of mind – knowing that your home will be backed up and ready when the power goes out.
Common questions
Powerwall or Powerwall Plus+?
Learn more about what makes the Powerwall+ unique, and whether it is the right option for your home and energy goals.
Learn More →
Lesson 04
Tesla Powerwall vs. Generator: What’s Best When the Power Goes Out?
What’s best when the power goes out – a Traditional Generator system or a Tesla Powerwall Whole-Home Battery System? We don’t have an end-all-be-all answer to that question. We’d love to see you go solar, but the best option for you will ultimately depend on your energy goals, preferences, and budget so let’s walk through a comprehensive list of pros and cons for both technologies.
Want a backup battery for your home but not sure if you need a solar battery or a generator? Randy is in the house to break it all down for you with Powerwall vs Generator.
Powerwall: Pros & Cons
Powerwall Pros
- Seamless Integration
- No Ongoing Maintenance
- Adaptive Technology
- Clean Renewable Energy
- 30% Tax Credit Incentive
- Energy Monitoring App
Powerwall Cons
- Weather Dependent Recharging
- Upfront Cost
Powerwall Pros
Seamless Integration – Silent, seamless integration into your home when you need that backup power. When the power goes out, in a matter of seconds, your Powerwall will be providing energy to your home. You may see the lights flicker during this transition, but that’s about it!
No Ongoing Maintenance – You’ve already purchased your solar system that produces energy to recharge your battery, meaning you have an endless supply of energy. And with that, the battery uses clean, renewable electrons to charge and discharge, meaning there are very few moving parts that could fail or require long-term maintenance.
Adaptive Technology – Compared to generators, the Powerwall is a relatively new technology designed with the expectation that it will continue to evolve. The good news is that these technology updates can be pushed to your Powerwall through firmware updates instead of needing to purchase a new piece of equipment. Tesla’s Powerwall software, working in conjunction with your home, will continue to develop with new functionality, giving you greater control over how you’re using your equipment during grid-up and grid-down situations.
Clean Renewable Energy – It’s as simple as that: You’re using clean, renewable energy by powering your batteries with the sun!
30% Tax Credit – There’s a 30% Federal Tax Credit that can be applied to batteries installed with or without solar! Thank you, Inflation Reduction Act of 2022 for restoring and extending said tax credit. 🙏 This means, when you file your taxes with the IRS, you’ll receive a credit worth 30 percent of your solar & battery storage system costs. Learn more here→
Energy Monitoring Software – Your Powerwall comes with a handy phone app that gives you really cool visibility into how your solar system is generating electricity, how your home uses energy, and the state of charge of your Powerwall. Seeing how those three factors work together willgive you greater control over your home’s energy consumption on-grid and off-grid. For an insider’s look at the functionality and daily use of Tesla’s App for monitoring your Solar + Powerwall, click here →
Powerwall Cons
Weather-Dependent Recharging – During an outage, your ability to recharge your battery revolves around the weather. Are you getting enough sun exposure on your solar panels to generate enough electricity to recharge those batteries?
Upfront Cost – Currently, batteries come with a significant upfront price point. We expect that cost will continue to work itself down over the coming years, but it still represents a significant investment as of now.
Generator (Portable or Integrated): Pros and Cons
Generator Pros
- Less Upfront Cost
- Controlled Fuel Source
Generator Cons
- Requires Fuel on Hand
- Harmful Exhaust
- Noisy Operation
- Ongoing Maintenance
- Non-Adaptive Technology
Generator Pros
Less Upfront Cost – Whether it’s a portable or whole-home integrated system, it’ll likely have a lower upfront cost less than a full solar + battery storage system.
Controlled Fuel Source – A generator’s fuel source is less weather dependent. If you’re tied into a natural gas line, you’ll have a stable fuel source. If your generator is fueled with a dedicated propane tank, it’ll be less reliable but likely still more reliable than days when the sun refuses to shine during an extended storm.
Generator Cons
Requires Fuel on Hand – Generators need fuel. To a degree, this is an advantage, but it does mean ongoing costs as you pay for natural gas or propane to run the generator.
Harmful Exhaust – As the generator is burning the gas mentioned above, it’s creating harmful exhaust which is emanating out into your neighborhood.
Noisy Operation – As the machine is running, it’s going to be noisy. It’s going to create decibel levels that might be a little irksome to you or your neighbors.
Ongoing Maintenance – A generator system is functionally an internal combustion engine, which requires a lot more moving parts compared to a battery. With those moving parts as the system gets older, there is a higher likelihood that you’re going to have ongoing maintenance costs, which translates to more money out of your pocket.
Non-Adaptive Technology – There’s an expectation that the generator system isn’t going to be as adaptive as modern battery storage technology as we move into the future. There are no software updates, or fancy apps to push new technology into the generator system. And with other systems in your home getting a facelift with updated technology (like a SPAN smart electrical panel for example), how they integrate with the generator will affect how your home is using electricity most effectively. The less efficient your backup source is, the more energy (and money) it is going to take to power your home during an outage.
FAQs
Although the grid will still be experiencing a blackout, and therefore, your home will be experiencing a power outage, you will likely not notice it if you have a battery backup system.
Worried about power outages in Carborro, NC? We’ve got you covered – We install solar and battery backup in Carrboro!
If your roof can withstand a hurricane, your solar panels will likely be right there with it. Solar panels are installed to withstand the various degrees of wind speed we see here in NC (from mountains to coast!). We will customize your system so it is installed according to the wind speed of your given location, based on the building code in your area.
Yes, solar panels are rated to withstand 1 inch of hail.
Resources Mentioned in this Module
- Tesla Powerwall Guide – your one-stop shop for all Tesla Powerwall questions
- Solar 101 Hub – it’s like an online textbook… but fun… and all about something you’re interested in
- SPAN Panel 101 – it’s a new product, and we know you’re curious
- Our YouTube Page – we make Brandon work day and night to produce quality videos, please give him love so he can see his children
- 30% Solar Tax Credit – long story short, you’re eligible for 30% of your solar system + battery in tax returns!!
What's Next?
Power security is as important as it has ever been.
If you’re worried about grid instability and want to feel more confident about your energy needs, or you’re just curious about what the buzz is around solar batteries and storage, get in touch with us! Our solar educators are happy to answer any questions and help you figure out if solar + batteries are the right fit for your home. Shine on!
Top 17 Powerwall Questions Answered
Answers to all your Tesla Powerall questions in one place! Check out our Tesla Powerwall Guide to learn about Powerwall specs, how battery storage + solar works, & more!
PDF Guide
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