Dipping Your Toes Into Storage – Is it Right for You?
Amy Heart
Vice President Policy, Sunrun
Texans experienced first-hand the devastating impacts from unreliable power and poor energy security from the recent spate of winter storms. As weather-related outages and calls to conserve increase, more families are turning toward batteries to supplement their home solar installation. In fact, Texas is one of the fastest growing states for home solar and batteries, and is the major driver for expected national increases in residential solar installations.
Batteries provide peace of mind. After Winter Storm Uri, I heard the stories from families who weathered the days-long power outages through their home solar and battery systems. Those families even shared their backup power with neighbors as outages lasted hours at a time. The sun came up and charged the batteries through their solar panels to keep their homes and other critical loads powered with clean energy. And, unlike a traditional generator, people don’t have to purchase fuel, thus avoiding fuel shortage risks.
As more people invest in clean, onsite generation and battery backup, consumers have more questions about why investing in this technology is so important.
How it works. Solar panels help manage or lower energy bills by generating onsite power from the sun. But to keep using that power at night or during outages, batteries are vital to store that excess energy. A solar and home battery system can be configured in a number of ways depending on your local utility requirements or your installer’s specifications, but here is what a typical system looks like:
- The solar panels convert light to electricity, which is then sent to an inverter.
- The inverter converts that electricity into power that can meet the home’s electrical needs.
- After the home’s needs are met, the battery is charged to full capacity.
- Any remaining excess electricity is sent back to the grid, to be used by the neighboring homes, typically at a rate agreed upon by the utility or Retail Electricity Provider (REP) to compensate you for your energy (which hopefully, depending on your utility or REP, will be a fair and reasonable rate that values the benefits of local solar).
- The battery stores the electricity to discharge at night or during a power outage.
Find what will work best for you. A qualified installer of solar and battery systems should answer your questions about the type of systems that best suits your needs and energy goals. Meanwhile, here are some considerations to keep in mind.
What do you need if the power goes out? Figuring out what you want to keep powered during an outage will help determine the size and price of your batteries. For instance, you can choose to have a few appliances to run on backup power, such as a refrigerator or hot water heater, or you can choose to back up the entire house.
How long do you want to be able to run your batteries in an outage situation? Consider if you want a battery system to power your home needs for one day or for two days. This will also help determine size; powering your home (with the goal to keep a few appliances running) during an outage for one day requires a much smaller system than backing up your entire home for two days. Typically, battery backups run only one day, especially with solar to recharge their batteries
How long will the battery last, and how much do I have to care for it? Most of the batteries used currently are lithium-ion, and come with extended warranties. Make sure to talk to your installer about the operation and maintenance plan and what happens at the end of your warranty plan.
To learn more about solar and batteries for your home or business, reaching out to the Texas Solar Energy Society is always the first place to start. But here are some other resources to guide you:
- For homeowners: Solar United Neighbors Battery Guide
- For technology details: SEI OnDemand classes
- Find REPs that offer solar-buyback options
- 40 Questions to Ask an Installer: American Solar Energy Society
We can do more. Backup power is great, but we can do even more with rooftop solar and home batteries. Creating policies and regulations that encourage rooftop solar and batteries will decrease costs and create a more reliable grid. Every home that installs home solar, or solar and batteries, helps relieve the stress on the grid during times of high demand – and eases our reliance on vulnerable transmission lines and centralized power plants. It can even provide power to the grid when it needs it most as well as localized, networked power to help communities access clean energy and survive power outages.
Texas has an exciting future ahead for rooftop solar and batteries. Let’s continue to power forward, together, to give every Texan the ability to create reliable, clean, and affordable energy.
About the Author
Amy Heart is Vice President of Policy at Sunrun and a member of TXSES’ Board of Directors.