Battery storage — Hertfordshire
EnSmart Battery Installation in Hertfordshire
EnSmart batteries for Hertfordshire homes, sized from your actual usage, with the grid paperwork, the seasons and the power-cut reality explained before you commit.
Hertfordshire has garden cities and new towns that still shape what goes on, and in, a house, which matters when the battery range you choose offers both indoor and outdoor packs. We install EnSmart SolarAll systems, the equipment in our own job photos, across our Hertfordshire towns. In Stevenage, the first new town designated, 44.9% of the built-up area’s households live in terraced houses; in Harpenden, 39.7% of the four wards’ households live in detached houses (Census 2021).
Those two numbers mean two different installations. The county overview is on solar panels in Hertfordshire, sizing and comparisons on battery storage, and town detail on battery storage in St Albans, Stevenage and Welwyn Garden City.
Quick answer
EnSmart in Hertfordshire:
- Our own work: EnSmart is the battery system in HCE's own job photos; the survey confirms whether it suits your home before anything is quoted.
- Cost: the Energy Saving Trust puts home battery storage at £1,500 to £10,000, with a 5 kWh system at around £4,600; a quote for your home comes from a survey of your usage.
- VAT: residential battery installations carry 0% VAT until 31 March 2027, then 5% from 1 April 2027.
- Grid: every battery is notified to, or approved by, the local network operator depending on its size (G98 or G99); the installer handles it.
- Power cuts: a standard grid-tied battery shuts down when the grid does; backup has to be designed in and is never assumed.
- Who fits it: HCE is a NAPIT member (73495), MCS-certified for solar PV and battery storage via NAPIT, and a HIES Consumer Code member.
Figures: Energy Saving Trust (batteries, updated 19 August 2026) · HMRC VAT Notice 708/6. Product facts are the manufacturer's, cited below.
How a home battery gets fitted in Hertfordshire
Four steps from first call to switch-on. No pressure at any stage, and a straight answer if it would not pay its way.
- Step 1
Your usage, not a guess
We look at when your Hertfordshire home uses power, especially evenings, and your tariff, because that, not the sunniest month, decides the battery size.
- Step 2
Sizing and siting
Where the unit can go (garage, utility room or an outside wall, as the manufacturer allows), whether it pairs with existing panels, and a written, itemised quote.
- Step 3
Installation and notification
Fitting and commissioning, with the battery notified to or approved by your network operator depending on its size. Backup in a power cut only if it is designed in.
- Step 4
Settings and handover
Charge and discharge set up around your tariff, the app explained, and the warranty documents in your hand.
How EnSmart fits Hertfordshire homes
In a Harpenden or St Albans house (76.5% of St Albans district’s households live in houses) the EnSmart ELV-W wall pack, rated IP50 and indoor-only, normally goes in the garage or utility room, with the IP65 SolarAll-H inverter beside it. In a Stevenage or Hemel Hempstead terrace, the understairs cupboard is the usual indoor option; failing that, the IP55 ELV-F floor packs are rated for outdoors away from direct sunlight. Welwyn Garden City and Letchworth add a step: in Letchworth and most of Welwyn Garden City, external changes need an estate consent that is separate from planning permission. If the inverter or a floor pack is going outside, we check that consent route before we fix anything; an all-indoor layout is one option we can design for.
All 14 Hertfordshire town centres we cover sit in UK Power Networks’ Eastern Power Networks area. EnSmart’s single-phase SolarAll-H runs 3–6 kW on the datasheet, so the inverter size decides the route: under G98 we notify equipment up to 16 A per phase (3.68 kW) after commissioning, and a larger unit needs a G99 application approved before work starts. A 4 kW inverter, at 17.39 A, is already over the line.
Hertfordshire: sunshine, the grid and local uptake
PVGIS puts a 4 kWp south-facing array at about 133 kWh in December (St Albans) to 141 kWh (Potters Bar), and at about 476 kWh (Borehamwood and Watford) to 487 kWh (Bishop’s Stortford) in June. On our arithmetic that is about 4.3 to 4.5 kWh on an average December day, under one 5.12 kWh pack, against about 16 kWh on a June day. DESNZ records about 24,567 solar PV installations across the nine Hertfordshire councils our towns sit in (end of 2025, our sum), and DVLA about 35,306 privately kept plug-in vehicles across them, up from about 25,976 a year earlier (our sum).
Ofgem’s 2024/25 figures for Eastern Power Networks show about 44.6 supply interruptions per 100 customers and about 32.5 minutes lost per customer, planned and unplanned, down from 46.2 and 35.6 the year before. An EnSmart system keeps circuits running in an outage only if the installation is designed for backup.
Local facts, sourced
EnSmart and Hertfordshire in numbers
Every figure below comes from a named public or manufacturer source.
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Of households in Stevenage’s built-up area, 44.9% lived in terraced houses, 22.9% in flats or maisonettes, 19.8% in semi-detached and 12.4% in detached houses at Census 2021.
Source: ONS, Towns and cities, characteristics of built-up areas, Census 2021 (tables 1c and 5c)
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Across Harpenden’s four wards, 39.7% of the 12,050 households live in detached houses and 27.8% in semis (our sum of ONS ward figures).
Source: ONS Census 2021, accommodation type (TS044 categories), Harpenden wards, via the ONS Census API
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St Albans City and District had 58,990 households at the 2021 Census, 76.5% of them in houses.
Source: ONS Census 2021, TS044 accommodation type, St Albans (E07000240), via the Nomis API
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In Letchworth and most of Welwyn Garden City, external changes to a home need an estate consent that is separate from planning permission.
Source: Welwyn Hatfield Borough Council, Estate Management Scheme; Letchworth Garden City Heritage Foundation
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PVGIS gives a 4 kWp south-facing array about 133 kWh in December in St Albans and 141 kWh in Potters Bar; June peaks at about 487 kWh in Bishop’s Stortford.
Source: European Commission JRC, PVGIS 5.3 (PVGIS-SARAH3 2005–2023; 4 kWp, 35° tilt, due south, 14% losses, building-mounted), runs of 15–16 October 2026 at each town-centre point
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DESNZ records 4,437 solar PV installations across East Hertfordshire and 4,214 across North Hertfordshire (43.22 MW) at the end of 2025.
Source: DESNZ, Renewable electricity by local authority 2014 to 2025 (Regional Renewable Statistics, published 29 September 2026), solar PV sites and capacity at end of 2025, as first published
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DVLA records 6,226 privately kept plug-in vehicles across St Albans district at the end of June 2026, up from 4,722 a year earlier.
Source: DfT and DVLA, VEH0142 licensed plug-in vehicles by local authority (published 23 September 2026), privately kept, end of June 2026 and end of June 2025
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All 14 Hertfordshire town centres on our battery pages sit in UK Power Networks’ Eastern Power Networks area.
Source: UK Power Networks, licence boundaries (Open Data Portal, modified 17 December 2024); NESO, GB DNO licence-area boundaries (3 May 2024)
Data last reviewed: October 2026
Battery storage across Hertfordshire
Town by town, with each town's own sunshine figures and network operator: battery storage in Borehamwood, battery storage in Potters Bar, battery storage in St Albans, battery storage in Watford, battery storage in Hemel Hempstead, battery storage in Harpenden, battery storage in Hatfield, battery storage in Welwyn Garden City, battery storage in Hertford, battery storage in Stevenage, battery storage in Hitchin, battery storage in Letchworth Garden City, battery storage in Cheshunt and battery storage in Bishop's Stortford.
The full specification is on our EnSmart page. For how sizing, warranties and pairing with panels work, see our main battery storage guide, and for the wider area, solar panels across Hertfordshire. For a longer read, see Hertfordshire home batteries: how five brands compare.
Comparing systems for a Hertfordshire home? See Tesla Powerwall in Hertfordshire, Sigenergy in Hertfordshire, EcoFlow PowerOcean in Hertfordshire and Fox ESS in Hertfordshire.
EnSmart in Hertfordshire: questions
Do I need estate consent for an EnSmart battery in Welwyn Garden City or Letchworth?
Possibly, if any part goes outside. In Letchworth and most of Welwyn Garden City, external changes need an estate consent separate from planning permission. The ELV-W wall pack is IP50 and lives indoors anyway; the SolarAll-H inverter can be indoors or out. We check the consent route for anything external before we fix it, and can design an all-indoor layout where the house allows.
Where does an EnSmart battery go in a Stevenage terrace?
Usually indoors, in an understairs cupboard or utility space, because the ELV-W pack is rated for indoor use only. If no indoor space works, EnSmart’s ELV-F floor packs are IP55 and can stand outdoors away from direct sunlight. The exact spot depends on ventilation, temperature and the cable run to the consumer unit, so we agree it at the survey.
Who tells UK Power Networks about my EnSmart battery in Hertfordshire?
We do. Every Hertfordshire town centre we cover is on UK Power Networks’ Eastern network. Equipment up to 16 A per phase (3.68 kW) is notified under G98 after commissioning; a larger SolarAll-H needs a G99 application approved before we start, which adds time to the job. We tell you which route applies when we quote.