FAQs about Home Battery Storage

Battery storage is normally installed for customers who already have, or are planning to get, a solar panel system. Why? Because in many cases you don’t use all the solar electricity you generate. That precious, excess electricity can be stored in a battery and then discharged to the home or office when you need it later in the day or at night.

A very popular battery for home or commercial use is the Tesla Powerwall. It can store 13.5 kWh, or units, of electricity.

Other brands include Alpha Smile, Sonnen, LG, Powervault and SolaX. There are several other makes, too, and we install all the makes and models currently available in the UK.

Over time, lithium-ion batteries gradually degrade hence, they can no longer hold 100% of their charge. For example, a battery that can store 10 kWh in Year 1 might only be able to store 9.5 kWh after a couple of years. Most batteries should last for about 10 years with acceptable degradation at 80%.

Yes. For example, you might be on an electricity tariff like Octopus Go that offers a peak rate of about 30p per kWh and an off-peak rate of 7.5p per kWh.

With battery storage, you can fill the battery at night with electricity costing you 7.5p, and then automatically have the battery discharge the electricity during the day when you would normally be paying 30p. All that night-time stored energy used during the day saves you 22.5p per kWh!

Panels produce electricity in direct current (DC), but your house needs power in alternating current (AC) for most appliances. Therefore, an inverter is required, to transform the energy from DC to AC.

In an AC coupled battery set-up, your battery has its own dedicated inverter, separate from the main solar inverter. Solar panels produce DC power, the solar inverter turns it to AC, with any excess flowing to the battery where it is turned back to DC by the battery’s inverter. If the battery is required to discharge, it uses its own inverter to turn the energy back to AC to meet the home demand.

With a DC coupled battery set up, both the battery and the solar panels share the same ‘’Hybrid’’ inverter. If your house does not need power, then the DC electricity from the panels goes straight to the battery without any conversion.

The main advantage of an AC coupled System is being able to cope with higher load peaks thanks to the combined capacity of both inverters, whereas DC coupled systems are restricted to one inverter’s output. DC systems however are ideal for low energy demand applications where the load peak is not that high, and the reduced number of conversions minimises losses and increases efficiency.

When it comes to batteries, monitoring platforms typically offer remote control capabilities, which allow users to control the battery’s charging and discharging remotely.

Users can optimize the performance of the battery and ensure that it is operating efficiently and effectively. Please note that features and capabilities of these monitoring platforms can vary depending on the manufacturer, and the specific product being used.

This will largely depend on how much excess power your system is sending to the grid. Even if you have a battery, there could still be enough excess to merit the installation of a Solar Hot Water Diverter, particularly during the summer months. We can usually determine whether this is the case through our software simulations.

If you have an EV charger your time of charge may impact the effectiveness of the HWD. Excess solar energy is generated during the day and would normally flow into your battery/and or HWD. However, if your car is plugged in and charging at this time, it will be prioritised over any battery and HWD, meaning that your water will not be heated. A case-by-case analysis is required, taking into consideration your system size, annual consumption, and daily habits to determine if a HWD is worth installing.

When deciding on the best position for your solar inverter and battery, there are a number of factors to consider.

Accessibility. Installers must be able to easily access the equipment for potential future maintenance work. Additionally, a 10kWh battery weighs over 100kg, stands 1 metre tall and over half a metre wide, making it impossible to lift up in lofts or manoeuvre in very tight spaces.

The environment. Too cool and batteries will not hold charge, and too hot they can overheat, leading to inefficiencies and possible fire risks.

Typically, batteries are installed in 1st floor locations, in ventilated environments, making them ideal for indoor spaces such as garages or storerooms. The likes of Tesla Powerwall 2 and SolarEdge Home batteries are also fit to be stored outside too. However, it would always be preferrable to install your solar batteries indoors, shielding them from the extreme elements that could potentially restrict performance.

Inverters are smaller and very robust. Preferably they go alongside your battery or close to your distribution board, but they can also be stored separately in tighter spaces. This can also vary based on which battery type (DC or AC coupled) you are looking to install. Component placement can be decided with our technician during a site survey.

A cycle refers to a complete discharge and charge. However, in reality, a battery won’t discharge fully before you recharge it. It is important to know how many cycles a battery is warrantied for.

Some systems do provide backup in a power cut and we can advise which is best suited to your requirements.