Everything You Need to Know About Solar Batteries

by Anna Gretz
April 20, 2016
Home Battery

By now, you’ve probably heard about solar batteries. Now, it’s time to hear everything.

Solar batteries are a game-changer in both the residential and solar markets, revolutionizing the way people use energy. Here’s everything you need to know about solar batteries. (Warning: As soon as you finish reading this, you’re going to want one. Immediately.)

Why Everyone’s Buying Solar Batteries

Everyone’s looking to ditch fossil fuels and hook up to the clean, reliable, free solar energy the sun dishes out every day. Solar panels have been popping up on rooftops at an unprecedented level, and the growing popularity of solar power has been driving down prices, and making the solar industry one of the fastest growing, most job-producing sectors in the world. But solar energy consumers want to take things to the next level. Households generating solar energy want the ability to power their homes even after the sun goes down, and protect the value of the energy they’re generating in-house, especially as debates over net-metering continue to rage on. Home batteries are the simplest and best way to take solar power further, keeping it in-house, and putting it to work in the evenings when you need it the most.

A Brief History of Solar Batteries

Though lithium-ion battery technology was introduced in the 1970’s, it took twenty years for it to really gain popularity. Lithium, the lightest of all metals, has the greatest electrochemical potential. This means that lithium provides the highest energy density per weight, far lighter and more efficient than the previously popular lead acid battery. Lead acid batteries can weigh a ton (not literally, but you get it), making them far more difficult to transport. The weight of lead acid batteries also makes usability much less convenient for residential customers.

The growth of lithium-ion technology has brought along with it many advantages. In comparison to batteries that have been popularly used in the past, lithium-ion batteries are cleaner, live longer, recycle better, and require much less maintenance. But the advantages don’t stop there. The solar battery market has skyrocketed because of its ability to solve the solar energy glitch--the fact that solar power isn’t constant (because the sun doesn’t shine at night). More on that later.

Solar Batteries are There, Whatever the Weather

When do we need energy the most? When it’s unbearably hot. Or freezing cold.

Back in the day, lead acid batteries did some serious struggling in hot and cold temperatures. Li-ion solar batteries to the rescue! Crazy-low temperatures like 0 degrees Fahrenheit will only take solar battery’s performance down ten percent or so. This means that even when your home battery gets cold, it can still store and provide your household with almost as much energy as it would on a normal day. When things warm up, solar batteries do have to work extra hard, but they can still stand the heat. At a temperature of 86 degrees Fahrenheit, solar batteries do continue to work, but performance jumps down 20%. If your home depends on your home battery for energy, reliability is key. Despite a performance drop, your solar battery isn’t going anywhere. Solar home battery capacity is there for you, whatever the weather.

Cleaner Clean Energy

How clean is clean energy, really? Compared to older technology like lead acid batteries, lithium-ion solar batteries have made major strides toward a greener future. Though the lithium in the lithium-ion battery does require mining, each battery requires less material than other battery types, minimizing the impact on the earth. Solar battery manufacturing plants are also looking to use renewable energy sources for power (a great example being the Tesla Gigafactory), which may result in an impressively small carbon footprint. Imagine manufacturing a home battery used to store renewable energy in a factory that runs on renewables and energy storage itself. It just makes sense, doesn’t it?

Long Live Solar Batteries

Solar batteries have a super high cycle life. This means that solar batteries can support a higher number of complete charge/discharge cycles before their capacity falls under 80%. This means that solar batteries don’t require frequent maintenance or replacement. After charging and discharging solar batteries thousands of times, they still remain highly functional. In fact, solar batteries are virtually maintenance-free, allowing owners to enjoy using the battery without worrying about permanent damage due to deep discharge. There are many other things in life that demand and captivate our attention. Your solar battery doesn’t have to be one of them. Your energy storage system can now be here to support you and your household, instead of the other way around.

Smarter Than Your Average Battery

New solar battery models have revolutionized residential energy storage by being connected and controlled by the cloud. “Smart” technology is infiltrating all devices (think phones and televisions) and solar batteries are no exception.

Smart solar batteries will give renewable energy users, like those with solar panels, huge advantages. Smart solar batteries have the ability to learn weather and energy trends, so they can focus on storing energy to make sure it’s available when the sun’s rays are not as strong. This practice can help maximize power usage, and also minimize the waste of energy when its abundant. Smart solar batteries also facilitate communication with owners, and are able to accept wireless commands, giving owners even more control over their energy.

The Freedom of Solar Batteries

Solar customers who have enjoyed the partial independence of producing their own energy during daylight hours have still been missing something: a solar battery, and with it, the ability to store energy during the day to use at night. With energy storage systems like solar batteries, solar customers no longer need to rely on the grid at night, when they often need power the most. This is where things really get good.

Using solar panels has been a great way to tap into a clean, renewable energy source. But solar batteries revolutionize the entire solar industry. Energy storage lets homeowners take advantage of blackout protection, and the freedom of living off the grid, without having to sacrifice their lifestyle. Solar batteries store energy during the day, when most customers aren’t even using the power generated by their solar panels. Energy storage owners come home to a solar battery charged full of energy, ready for whatever evening has in store.

Big Names in the Solar Battery Industry

If you’re thinking about doing some reasearch into solar batteries, here are some big names you should know:

The Tesla Powerwall- The Powerwall from Tesla has gotten a lot of attention for sleek design, but the real headliner is its price. The 7 kWh daily cycle battery is available to installers for a mere $3K. The 220 lb, indoor/outdoor battery comes with a 10-year-warranty, with deliveries and installations already underway worldwide. Tesla has also announced that it will be introducing a new and improved Powerwall 2.0 in the near future. In typical Tesla fashion, the company is always tweaking and improving their product to make it the best solar battery on the market… but they’re not the only one.

LG-Eguana’s AC Battery- LG Chem teamed up with Eguana to create a fully functional and durable home battery, perfect for residential use. The battery boasts frequency regulation, demand response, and feeder voltage support. External communication is also featured through HMI display, and the battery’s smart technology does the grid monitoring for you. The Eguana AC Battery allows you to use your own photovoltaics, regulate power frequency, and is rated for reliability and long term performance. The AC Battery has a fixed or adjustable power factor, and provides 5000 VA of continuous power up to 114 degrees F. Grid monitoring is active in all states, and the self consumption of power is 3 watts when asleep, and 30 when operating. The Eguana AC Battery operating temperature ranges from 14 to 114 degrees Fahrenheit, and can be wall mounted for indoor or outdoor use. The dimensions of the battery itself are 44” by 30.8” by 14.5” and it weighs 199 pounds.

Sonnenbatterie- The energy storage system from Germany-based Sonnenbatterie is “more than just a battery.” It’s a smart storage system that automatically capitalizes your home’s energy consumption. A particularly interesting feature uses a learning algorithm along with weather forecasts to predict how much solar will be generated, and how much will be needed or stored by the household each day. On sunny days, it can delay charging until the afternoon, when photovoltaics will have the highest output. This home battery also lets you view power generation and usage in real time.

Every Home Needs a Solar Battery

Those are Tesla CEO Elon Musk’s words, not ours, but we totally agree. According to Musk,

“Without a home battery, excess solar energy is often sold to the power company and purchased back in the evening [at a higher price],” Musk argues “The mismatch adds demand on power plants and increases carbon emissions.”

We believe solar and batteries are better when they’re together.

Whether you’re trying to go greener, maintain the value of your solar energy, or set up reliable back-up power, solar batteries are your answer. That’s why Swell is here: we believe solar and batteries are better when they’re together.