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As the global community grapples with climate change’s adverse impacts, the shift towards renewable energy sources has become increasingly urgent. Power produced by solar panels has emerged as a key player in transitioning to a cleaner, more sustainable future. However, the intermittent nature of solar energy production presents a challenge. This is where solar battery storage comes into play.
Solar batteries are energy storage devices designed to store the electricity generated by solar panels. These batteries typically use advanced chemistry, such as lithium-ion and lead-acid, to store energy efficiently and reliably. When the best solar panels produce more electricity than is needed for immediate use, the surplus energy is sent to solar panel battery storage. This stored energy can be used when the panels are not producing power, such as at night or on cloudy days.
Additionally, by storing this excess energy, you can utilise it during peak hours when electricity rates are higher. This reduces the amount of grid-supplied electricity you need to purchase, leading to lower electricity bills.
While solar panel battery storage systems allow you to consume more solar-generated electricity, you may still produce more energy than you need. You can benefit from the Smart Export Guarantee (SEG) in such cases, as it allows you to sell excess solar-generated electricity back to the grid by offsetting your mains usage or receiving a direct payment.
Solar batteries are crucial in making solar energy systems more reliable and versatile. They help to mitigate the intermittent nature of solar power production, allowing homeowners to use the energy solar panels produce even when its cloudy.
Additionally, solar batteries can provide backup power during grid outages, enhance grid stability, and promote energy independence by reducing reliance on fossil fuels or grid-supplied electricity.
Finding the right solar batteries for your system involves several steps. It’s important to consider factors such as your energy needs, solar panel costs and budget, and system compatibility when selecting the ideal solution.
Begin by evaluating your daily energy consumption and patterns. Determine the amount of solar-generated electricity you need to store for use during non-production hours. This will help you identify the appropriate battery capacity and discharge rate required to meet your energy needs.
Solar batteries are available in several types, such as lithium-ion, lead-acid, and flow batteries. Each has advantages and disadvantages regarding performance, cost, lifespan, and maintenance requirements. Research the different battery technologies to determine which best suits your needs and budget. The two most commonly seen types are:
The capacity of a solar battery is measured in kilowatt-hours (kWh) and indicates the amount of energy it can store. The power rating, measured in kilowatts (kW), determines the electricity the battery can deliver at any given time. To find the right battery storage, consider both the capacity and power rating to ensure the battery can store enough energy and deliver the required power to meet your energy needs.
Ensure the solar battery you choose is compatible with your existing solar panel system, including the inverter and charge controller. Some solar batteries may require specific inverters or additional equipment for seamless integration. Consult your system manufacturer or installer for guidance on compatibility.
Solar battery costs vary significantly depending on the technology, capacity, and brand. Compare the prices of different batteries and consider installation costs, maintenance requirements, solar panel grants and potential savings on electricity bills. Also, take note of the warranty offered by the manufacturer, which typically covers battery performance and lifespan. A longer warranty period with favourable terms may indicate a high-quality product.
Solar battery installation involves technical expertise and knowledge of electrical systems. Consult a professional solar panel installer or an electrician with experience in solar battery installations to ensure proper system integration.
Green Building Renewables is a Yorkshire-based solar and renewable energy company. John told us that many homeowners with roofs unsuitable for solar panels are installing battery-only systems.
Batteries allow homeowners to make full use of smart tariffs. These tariffs vary electricity prices throughout the day, offering reduced rates during off-peak times – such as late night when demand is low or during periods of high renewable energy production. Batteries can store this cheap electricity for use later when tariffs are higher, saving homeowners money. This is called ‘load shifting’.
John said that although owners of battery-only systems don’t make the big savings that solar system owners do, they still enjoy significantly reduced energy bills with a smaller initial outlay.
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Once you have fitted solar PV panels to your roof, the next challenge is to make sure you use as much of the energy generated as you can. This then might tempt you to install a solar battery as well. It may seem like a no-brainer – generate energy during the day, use it at night – but the pros and cons of fitting such a product are largely down to the pounds and pence.
Let’s take an average example of a battery capacity of 5kW. You will not have enough energy spare from your solar panels in winter, unless you have a very large array, so we will optimistically assume you can charge the battery 300 days a year and we will also assume that the energy generated is free (you have not allocated the generation against the payback of the solar panels themselves). The cost of peak electricity is around 35p.
Therefore 35p x 5 x 300 days = £525 a year. A decent battery may cost around £3,000 (it may be more or less, depending on what you buy and where you buy it) to install, so you are looking at a minimum of around six-year payback. So, payback might be an advantage or a disadvantage, depending on how the numbers stack up for you.
The demand for batteries is now very high and the raw materials required to make them leave many unanswered environmental questions. This is my biggest concern. So, can a solar battery make financial sense? It certainly looks like it can. Do I want a home battery? Yes. Should I have a home battery? I am not sure.
Project Solar sells a range of solar storage batteries from several manufacturers.
The TP58 is a lithium-ion battery intended for residential solar energy storage applications. It’s equipped with multiple safety features, including overcharge and over-discharge protection, short circuit protection, and thermal management systems, and comes with a 10-year warranty.
The SolaX Triple Power battery series is designed to be scalable, allowing users to connect multiple batteries in parallel to increase the overall energy storage capacity. This flexibility makes it easy to customise the storage system according to specific energy requirements.
Fox ESS energy storage systems use lithium-ion batteries to store and manage the energy generated by solar panels efficiently. It offers a range of batteries with varying capacities to meet different energy storage needs, allowing users to select one that best fits their requirements.
BSB Power is a Chinese battery manufacturer that produces a wide range of batteries, including the FAG series of sealed lead-acid solar batteries. BSB Power says its batteries exhibit a low self-discharge rate, ensuring they can retain their charge for an extended period when not in use.