Can I have a battery without solar panels?
Yes, and since 1 February 2024 it is zero rated for VAT in its own right. A standalone battery charges from cheap overnight grid electricity and runs your house through the expensive part of the day. It works on a shaded roof, a north facing roof, an upper flat, or a house where the roof is not yours to touch. What it needs is not sunshine, it is a time of use tariff and a household that uses enough electricity during the day to make shifting it worthwhile.
Will my battery keep the lights on in a power cut?
Not unless it has been specified to. G99 requires a grid tied inverter to disconnect the instant the mains is lost, so that your system cannot energise a line SSEN engineers are working on. The default behaviour is to shut down, however full the battery is. To get power during an outage you need an EPS, an Emergency Power Supply output with a relay that isolates part of the house and lets the inverter run it as an island. Changeover takes about 10 to 20 seconds and an EPS output is typically 3 to 5kW, so lighting, fridge, freezer, router and boiler controls rather than the shower. It is a chargeable option, quoted at survey.
How much will a battery save me each year?
On tariff shifting alone, a family home using 3,500 kWh a year with a 10kWh battery on a time of use tariff at 8p overnight and 30p daytime pays roughly £507 a year, against roughly £840 on a standard flat 24p tariff. That is about £333. At £3,500 to £5,000 fitted, that is a ten to fifteen year payback on tariff shifting by itself, so we would not sell you a battery purely as an investment. Add solar self consumption on top, and the resilience during an outage, and the case gets much stronger. We model it against your real consumption at survey rather than quoting a generic figure.
Do I need an electric car to benefit?
No, but it helps more than most people expect. The cheapest overnight tariffs, such as Intelligent Octopus Go at around 7.5p between 11:30pm and 5:30am, require a compatible electric vehicle or smart charger to qualify. A home battery on its own does not get you onto them. If you do have an EV, the cheap rate during that overnight window applies to the whole house rather than just the car, which is why households with a charger already fitted get the most out of storage. Other time of use tariffs exist without an EV requirement, with a smaller spread between the cheap and expensive rates.
Where in the house can a battery actually go?
Usually an attached garage, utility room, plant cupboard, porch or outbuilding. PAS 63100:2024, the fire specification for battery storage in dwellings, says a battery should not go in a room intended for sleeping, and should not go on a means of escape that is not a protected escape route, which rules out most landings, staircases and hallways. It also sets specific provisions for loft spaces. PAS 63100 clause 6.1.3 caps stored energy at 20kWh per enclosure. On tight harbour terraces this is sometimes the deciding factor rather than price, and we establish it at survey.
How much does battery storage cost in Peterhead?
A 10kWh battery fitted, whether standalone or retrofitted to existing solar, is £3,500 to £5,000. A 15kWh unit is £5,000 to £7,000. A 4kWp solar array with a 10kWh battery installed together is £10,000 to £12,000. All of these are zero rated for VAT until 31 March 2027, after which the rate becomes 5%. An EPS backup output and whole home backup are chargeable options priced after the survey, and a consumer unit upgrade, where the existing board cannot take the new circuit, starts at £550 + VAT.
Do I need permission from the network before switching it on?
Yes. Battery storage almost always exceeds the 3.68kW per phase threshold for the simpler G98 notification, so it needs a G99 application to SSEN that is approved before the system is energised, not notified afterwards. We submit it as part of the job. If an installer does not mention grid approval at all, ask who is doing it and when.
What battery brands do you fit, and what chemistry?
SolarEdge, Fox ESS, Alpha ESS and SolaX, all lithium iron phosphate. LFP is what the domestic storage industry has settled on because it is thermally stable and lasts for many more cycles than the nickel based chemistries used in phones. Warranties reflect it: Fox ESS typically 10 years on the EQ and EP ranges and 12 on the newer CQ6, with round trip efficiency in the 95% to 98% region, and SolaX Triple Power 10 years across 5.8kWh modules stacking to around 23kWh.
How long does a battery last, and what happens at the end?
Warranties on the units we fit run 10 to 12 years, and they are written as a retained capacity figure rather than a simple on or off. A battery does not stop at the end of its warranty, it holds less than it did when new. LFP chemistry degrades slowly, which is a large part of why it is the chemistry we fit. The inverter is generally the component with the shorter service life, and on a DC coupled hybrid system it is the part most likely to be replaced first.
Does Part P apply in Scotland?
No. Part P is a section of the Building Regulations for England and Wales. Scotland has Building Standards, administered by the local council, and the mechanism is a building warrant rather than a notification. There is no Building Control body to notify here. Peterhead sits within Aberdeenshire Council. Fitting a battery in an existing house is electrical work rather than a structural alteration, so a warrant is not normally in play, but the installation is tested and certified to BS 7671 regardless.