What to expect from a solar battery installation

Helpful video reference. This guide uses Artisan Electrics' video "Solar and Battery Installation: What to Expect (UK Homeowners Guide)" as the video reference. Artisan Electrics are a Cambridge-based renewable energy installer with one of the largest UK electrical YouTube channels. Their walk-through covers the permissions process (including G98 and G99 grid applications), what happens on-site, and the difference between on-roof, in-roof and battery-only systems. Highly recommended before approaching any installer for a quote.

1. Is your home suitable?

Before approaching installers, think through a few basics. Do you already have solar panels? A battery works best when it has a solar system to charge from, though standalone batteries that charge on cheap overnight tariffs (such as Octopus Go or Agile) are increasingly popular. Check your electricity bills to understand your usage patterns: the aim is to size the battery to cover your evening consumption without oversizing.

You also need somewhere to put it. Garages are ideal: good ventilation, away from living spaces and typically close to the consumer unit. Utility rooms on an external wall work too. Updated fire safety guidance under PAS 63100 means loft installations are now discouraged. A good installer will assess placement as part of the survey.

2. Choosing a battery and comparing quotes

Look at battery capacity in kilowatt-hours (kWh) and peak output in kilowatts (kW). A 10 kWh battery running at 5 kW peak covers most domestic evening loads. Check whether the unit offers EPS (Emergency Power Supply) backup: this allows the battery to island from the grid and keep essential circuits running during a power cut. Not all batteries offer this and it significantly affects the installation complexity and cost.

Any installer quoting for this work must be MCS certified. Check the MCS installer database at mcscertified.com before signing anything. The quote should explicitly include DNO notification fees and any G99 design costs if applicable. If an installer says they "don't bother" with DNO notification, walk away.

3. DNO notification: G98 versus G99

Your District Network Operator (DNO) must be informed before your battery system exports electricity to the grid. The process depends on the size of the system:

• G98 (up to 3.68 kW per phase): Your installer notifies the DNO after installation and commissioning. Straightforward and quick.
• G99 (over 3.68 kW per phase, or 11.04 kW for a three-phase connection): Pre-approval required before any work begins. The DNO has up to 12 weeks to assess and respond. Your installer submits a technical design pack. Most domestic batteries are G98, but some higher-capacity hybrid systems cross the threshold.

If you are adding a battery to an existing solar system, the combined export capacity of both must stay within the G98 limit, or G99 applies. A competent installer calculates this before quoting.

4. What happens on installation day

A typical battery-only installation takes one to two days. Combined solar and battery installations generally take two to three days. The sequence runs roughly as follows:

First, the installers isolate the consumer unit and carry out any preparatory cable work. The battery unit is mounted on the wall, secured to the specified bracket, and connected to the solar inverter (or to a new sub-board if it is a standalone battery). CT clamps or energy monitoring sensors are fitted if the system requires them. The consumer unit is updated with appropriate protection: an RCBO or RCD protecting the battery circuit is standard.

Then comes commissioning: the battery management system is configured, the app or monitoring platform is set up, and the installer checks charge and discharge cycles before signing off. This takes an hour or two and is worth being present for, so you understand the system.

5. What you should receive at the end

A proper installation generates paperwork. You should receive an MCS certificate for the system, an Electrical Installation Certificate (EIC) or Minor Works Certificate for the electrical work, and confirmation of DNO notification. File these somewhere safe: you will need them if you sell the property, make an insurance claim, or add to the system later.

The installer should also register the system with your electricity supplier if you want to export surplus electricity under the Smart Export Guarantee (SEG). This is separate from the DNO notification.

6. In the weeks after installation

Check the battery app or display in the first few weeks. You are looking for the battery charging from solar during the day, discharging in the evening, and either sitting at zero or charging from the grid during cheap overnight hours if you have a time-of-use tariff. If the battery is not cycling as expected, contact the installer promptly: early commissioning issues are almost always resolvable quickly when caught early.

When to call us

Richard works with qualified solar and battery contractors and can advise on whether a quote covers what it should. For east Kent properties, contact Richard for an honest conversation about what a home battery installation involves before you commit to a supplier.