Solar batteries provide many benefits for property owners, including increased savings and disaster resiliency. If your electric utility uses a time-of-use (TOU) rate structure or demand charges, having solar battery backup can save you money on your electric bill.
Aside from saving money on your electric bill, solar batteries can provide backup power in the case of a grid blackout. If the power goes out and you have solar electricity stored in a home battery, you can power your home for a period of time using the electricity you generated with your solar panels. The traditional method of powering a home during a blackout is by running a standard diesel generator that costs extra money to fuel and maintain and produces greenhouse gas emissions.
Solar batteries work by storing energy produced by your solar panels for later use. In some cases, solar batteries have their own inverter and offer integrated energy conversion. The higher your battery’s capacity, the more solar energy it can store.
People often ask ‘Can solar panels work at night?’ The short answer is no. But with a battery, in effect they do. During the day, when solar panels are generating more power than your property is using, excess power is diverted to the battery for use later. When the sun goes down, or if you’re using more energy than your panels are providing, the battery will kick in to give you power and prevent drawing from the grid.
The key distinction between an AC-coupled and DC-coupled system lies in the path electricity takes once it is produced by solar panels. Solar panels generate DC electricity that must be transformed into AC electricity for your home’s appliances. However, solar batteries store electricity in DC form.
In an AC-coupled system, the flow of solar electricity starts with DC power generated by solar panels. This DC electricity then passes through a solar inverter, where it is converted into AC electricity. The AC electricity can directly power your home appliances or be directed to another inverter that converts it back to DC. This DC electricity is then stored in a battery system for later use. It is important to note that in AC-coupled systems, any electricity stored in the battery system undergoes three separate inversions before it can be utilised.
In a DC-coupled system, the flow of solar electricity starts with DC power generated by solar panels. This DC electricity directly travels from the solar panels to a charge controller, which efficiently directs the electricity into a battery system. Unlike AC-coupled systems, there is no need to convert the solar electricity from DC to AC and back again before storing it in the battery. Therefore, the electricity from the solar panels undergoes a single inversion (from DC to AC), either as it flows from batteries to your home electrical setup or out to the electrical grid.
Historically, AC-coupled battery storage setups have been more common for residential and commercial solar installations, but as more DC options become available, DC coupling is gaining in popularity.
AC-coupled solar battery systems offer significant advantages, particularly in terms of installation convenience, especially when retrofitting storage setups. The simplified installation process reduces the labor and time required for solar installers, ultimately resulting in lower upfront costs.
Furthermore, AC-coupled systems provide an additional benefit by allowing batteries to charge from both solar panels and the grid. This flexibility ensures that even if your solar panel system doesn't generate sufficient electricity to fully charge the battery, you can still rely on the grid as an alternative source. This feature proves useful for ensuring battery resiliency and taking advantage of electricity rate arbitrage benefits. It is also essential for participating in utility energy storage pilot programs or other demand response initiatives, as the electric utility may need control over the battery's electricity flow.
However, there are some drawbacks to consider with AC coupling. Since AC-coupled systems require three separate inversions of stored solar electricity before it can be used by home appliances, there are small efficiency losses associated with each inversion. The conversion process between AC and DC, or vice versa, leads to minor efficiency reductions. Consequently, the more inversions that occur, the greater the overall reduction in system efficiency. Typically, inverters exhibit efficiency losses of a few percentage points.
DC-coupled solar energy systems offer a notable advantage in terms of efficiency compared to AC-coupled systems. Unlike AC-coupled setups that involve three separate conversions between AC and DC for stored solar electricity, DC systems require only a single conversion, resulting in superior overall system efficiency.
However, it is important to note that DC-coupled options tend to be more complex to install, which can lead to increased upfront costs and installation time.
It's important to note that the specific benefits and performance of FOX ESS Solar Batteries and Storage may vary depending on factors such as your energy consumption, solar generation capacity, and the overall configuration and setup of the system. It's recommended to consult with our professional installers or contact FOX ESS directly to assess the suitability of their products for your specific needs.
Our bespoke systems can be found in businesses across the UK. Positive Energy Solutions has been instrumental in shaping the way we can live more sustainably, without adversely affecting the conditions for future generations. Surrounded by beautiful hills, dales and valleys, Positive Energy Solutions is situated in the heart of the High Peak, Derbyshire. It is here where we design our intelligent renewable energy solutions for businesses across the country. Every project is dealt with personally, professionally and tailored to your exact needs.
Simply use our remote survey form or alternatively fill out the form on our contact us page and one of our energy experts will get in touch to discuss your options.