What are solar batteries, and what are they used for?

Every type of solar battery is a key ally for energy systems, allowing electricity to be stored and ensuring a continuous power supply. They are essential for off-grid energy installations and hybrid systems that aim to provide greater energy independence and reduce electricity costs. They are also extremely useful for single-family homes or buildings in remote areas where power supply is inconsistent or blackouts are common.

How do solar batteries work?

Now that you know about the concept of a solar battery, let’s get into the details of how they work. These batteries store energy in chemical form and release it as electricity when photovoltaic solar panels aren’t generating enough power to meet demand.

During peak sunlight hours, solar panels absorb energy and convert it into electricity, which is stored in the batteries. When demand exceeds the panels’ production capacity or at night, the battery supplies the stored energy. They can also provide a higher current intensity than a solar panel alone, making them ideal for days with high energy demand.

Most types of solar batteries operate through a charge and discharge cycle that occurs in three phases:

• Electricity generation: photovoltaic solar panels convert sunlight into direct current (DC) electricity.
• Storage: the electricity generated by the panels is stored in the solar battery through a charge controller. This controller helps control energy flow to prevent overcharging.
• Distribution: when energy is needed, the battery releases electricity in direct current (DC). If the system requires alternating current (AC), an inverter will be needed to perform the conversion.

Types of solar batteries

Now that you know what a solar battery is and how it works, let’s explore the different types available:

Lead-acid batteries: a traditional and cost-effective option for solar panel installations. They are suitable for small systems. However, due to their affordability, they are also recommended for large-scale installations that require a significant initial investment.

Gel and AGM batteries: considered the successors of lead-acid batteries, these have evolved with improved materials. They offer greater safety and require minimal maintenance.

Flow batteries: currently recognised as an innovative option due to their long lifespan and suitability for industrial installations and large-scale energy systems with high consumption demands. They have a long lifespan and variable storage capacity.

Nickel-cadmium batteries: less common but extremely robust and resilient, as they can operate in extreme conditions. Like flow batteries, they are frequently used in industrial contexts.

Lithium-ion batteries: known for their high efficiency, energy density, long lifespan, and greater storage capacity. They are commonly used in residential systems and small commercial establishments.

Endesa provides these lithium-ion batteries for free when you install solar panels with us (promotion valid until 31 May 2025 or while supplies last).

By installing a storage battery alongside your Endesa solar panels, you can save up to 70% on your electricity bill and achieve a quick return on your investment. Plus, you can monitor real-time production, consumption, and battery status using our free Endesa Clientes (Endesa Customers) app for iOS and Android. Additionally, Endesa guarantees quality, durability, and space efficiency, as our M, L, and XL batteries (for 8, 10, and 12 panels) are Pylontech, a global leader in home energy storage solutions. Their compact design integrates an inverter, charger, and batteries in a single unit.

When you choose Endesa, you get up to 10 years of warranty on the battery and 12 years on the panels, plus financing options for up to 120 months. But we won’t give away all the details just yet—you can find all the information below:

The perfect combination of batteries, solar panels, and customers

Birds of a feather flock together! Some combinations simply work better than others—they allow energy to flow more efficiently. Yes, we’re still talking about solar batteries, even though it might sound like a shift in the conversation. The compatibility between batteries and panels is crucial to maximising energy system performance. And the customer also plays a role, as selecting the right solar battery depends on their specific needs.

High-efficiency panels pair best with lithium-ion batteries due to their ability to maximise energy storage, while lead-acid batteries are a great option for large installations with moderate-efficiency panels.

Choosing the right combination helps customers optimise their investment, ensuring each system component works in synergy for greater efficiency and cost savings.

But which batteries are best for different solar panels?

• For monocrystalline panels: lithium-ion batteries are ideal due to their high efficiency and storage capacity.
• For polycrystalline panels: gel and AGM batteries provide excellent performance and safety.
• For thin-film panels: lead-acid batteries are a cost-effective and efficient choice.

And which batteries are best for different types of users?

• Residential users: lithium-ion batteries are ideal due to their efficiency, longevity, and compatibility with most home systems. Gel and AGM batteries are also good alternatives, given their safety and low maintenance characteristics.
• Small businesses (SMEs): flow batteries and lithium-ion batteries are recommended for their durability and their ability to supply and regulate high energy volumes. Lead-acid batteries may be an alternative for those looking to minimise initial costs, especially for large-scale systems with a limited budget.
• Industrial users: flow batteries and nickel-cadmium batteries are best for large companies due to their high energy capacity and long lifespan.

It’s essential to choose the right solar battery for your needs, but you should also consider the best solar tariff that aligns with your daily energy consumption.

What are the benefits of using solar batteries?

Installing solar batteries at home offers numerous benefits. For instance, they contribute to greater savings on your electricity bill and provide electricity autonomy by utilising solar power without fully depending on the grid. Besides, they promote clean, sustainable energy and help reduce your carbon footprint by optimising renewable resources.

Solar batteries store excess energy generated by the panels, preventing electricity from being wasted and making solar energy use even more efficient. Currently, systems without batteries return surplus energy to the grid in exchange for compensation. However, installing solar batteries with a 15- to 20-year lifespan allows customers to store and use that energy instead.

Among the many benefits of a battery for photovoltaic solar panels is the guarantee of a continuous power supply throughout the day, providing great protection against power outages or blackouts, especially in rural or remote areas.

In summary, solar batteries are an essential tool for saving energy and money. Furthermore, we make the most of solar power while living each day knowing that we are contributing to environmental well-being. They provide an efficient solution to maximise the use of solar energy and enhance energy independence in homes as well as in large, medium, and small businesses.

That said, it is essential that you choose the right battery, solar panels, and Endesa tariff based on your specific needs. That perfect combination will provide autonomy, efficiency, and cost savings for your home or business’s electrical system.