How Solar Energy is Stored

Battery storage

Since the early 1970s, solar power has become more and more popular amongst homeowners and business owners alike, it has proven itself to be the most efficient known energy source, and the price of purchase and installation has gone down while the energy savings for people continue to rise. While solar energy’s popularity continues to increase there are still very few people who understand exactly how it works, and even though understanding the minute details and complexities isn’t necessary, it’s helpful to understand how your panels generate power, and what happens to that power when it’s generated.

What Happens To Excess Solar Energy That Is Not Used?

One question that a lot of people don’t have the answer to or don’t even know to ask is what happens when your solar panels generate more energy than your home can actually consume? The answer is quite simple, either that excess power gets sent back to your energy company, and you’ll receive a credit for that electricity, or you keep the excess of power in a storage unit.

How To Store Solar Energy

Solar batteries are the way to go when it comes to storing your excess solar energy, and luckily for consumers everywhere, there are plenty of options to choose from.

Some of the most popular solar energy batteries are:

  • Tesla Powerwall – Tesla is well known across the country for its innovative technology in all markets, whether it’s their self-driving cars or their flame throwers, so it’s no surprise that they were one of the first and most successful companies to enter the solar energy market. The Powerwall is a lithium-ion battery with a similar design to the batteries used in their famous vehicles.
  • SunPower SunVault – With SunVault™, you can enjoy user-friendly application, valuable energy and financial savings, and worry-free ownership.  SunVault Storage systems are easy to use, and the software provides seamless integration with your solar network system.
  • Sonnen Eco – Germany entered the solar battery market with its own version of a solar battery in the form of the Sonnen Eco. The Sonnen Eco is a lithium ferrous phosphate battery that is easily distinguished from the rest of the products on the market because of its self-learning software. This helps homeowners to manage their time-of-use electricity rates.
  • LG Chem RESU – This solar battery is brought to you by the technology giant, LG. The RESU is a lithium-ion battery that comes in various sizes; unfortunately, only one of their models is available in the US.
  • Pika Energy Harbor Smart Battery – The Pika Energy Harbor Smart Battery is what you get when you combine a startup like Pika Energy with a tech giant like Panasonic. Pika Energy partnered with Panasonic to develop a lithium-ion battery cell to pair with the Pika Energy Island inverter. Unlike some of the other batteries we mentioned, the Harbor Smart Battery is specifically intended to work with a solar panel system.

While the companies we mentioned above are already dominating the solar battery market, there are some companies that are beginning to enter the playing field. Companies like Nissan and BMW, especially, are beginning the research and development phase and already have a large market share in other areas.

Factors To Consider When Choosing A Solar Battery

There are some criteria to keep in mind when making your solar battery selection. The most essential items to keep in mind are:

  • Capacity – The capacity of the battery refers to the total amount of energy that the battery can store, which is measured in kilowatt-hours. Most solar battery systems are “stackable,” which means you can add additional batteries to the stack to get extra capacity.
  • Power – Capacity and Power should usually be reviewed in tandem because one without the other won’t do you much good. Power refers to the amount of electricity that a battery can deliver at one time. A battery with a high capacity and a low power-rating will deliver a low amount of electricity for long periods of time, while a battery with a low capacity and a high power-rating will deliver enough electricity to run your home but only for a few hours.
  • Round-Trip Efficiency – The round trip efficiency of your battery refers to the amount of energy that can be used from the battery compared to the amount of energy that entered the battery for storage. For instance, if 5 kWh enters the battery for storage and you are only able to get 4 kWh of useful energy back, then your battery has a round trip efficiency of 80 percent.
  • Battery Life – Just like the battery in your cellphone, a solar battery has a limited lifespan, and in the same way, as it gets older, it’s battery life grows shorter. Before purchasing your solar battery, check how long the estimated battery life is.

How Do Solar Batteries Work?

Your solar-powered battery will act as a backup power source in the event that your panels are unable to generate power. For instance, if there is a blackout your panels will automatically shut off, this is to protect your device and your home from power surges and residential fires, and in these instances, your home will be able to rely on the solar battery for power.

Storing Energy For A Cloudy Day

A back-up battery will even help you on a cloudy day. As we’ve written about before, your solar panels continue to generate electricity on cloudy days, but it’s at a much less efficient rate. In these cases, you might not be producing enough power to run your household, which is where your solar battery comes into play. You can dip into some of those reserves to help power your high energy appliances on those cloudy days.

How Long Do Solar Batteries Last?

The lifespan of a solar battery can vary based on a number of factors, including the type of battery you have. For example, a Tesla Powerwall system can last up to 10 years, but not every back-up battery system can match this. On average, most batteries can last 5 to 15 years. The frequency with which the battery is used, and if it is properly maintained and stored are factors that can also influence how long the solar battery may last.

Keep Your Power Running With A Solar Battery

No matter which battery you decide to go with, or how you decide to use your battery, there is no denying just how beneficial they are for your solar panels and for your home. Solar technology has been a long time coming, but that doesn’t mean it’s slowing down any time soon. Private companies and the government are both dedicated to making solar power as efficient and cost-effective as possible for a better tomorrow.

How Energy Concepts Can Help

For more information about solar power, whether it’s regarding the cost, the installation process, or the storage of energy, contact our experts at Energy Concepts. Our company has over 25 years of experience in the Fresno solar industry, and we are ready to transition every home to solar power. Call us today or visit our website to learn more about the benefits of going solar!