Home Battery Storage UK

How it works

1

One 5 kWh box. Inverter included.

STREAM or AC 5000 all-in-one. The inverter sits in the unit, so there is no separate kit to match.

2

Electrician-wired to your consumer unit

Hardwired to BS 7671 with a G98 grid connection. This is not a plug-in battery. Plugging a battery into a UK socket and feeding the house is not legal.

3

Add expansion packs if you grow

Start at 5 kWh. If your usage rises, expansion packs stack on the same system so you are not stuck with the first box.

The maths

9.5p

Night rate
(Octopus Go 12M Fixed)

33.6p to 37.4p

Day rate
(varies by region)

23p to 27p

Saved per kWh
(one cycle a day)

Up to £420 to £490

Best-case annual savings
(5 kWh battery)

Best-case range for a 5 kWh battery on Octopus Go 12M Fixed, direct debit, inc VAT, checked 10 October 2026: night 9.5p/kWh, day 33.555p/kWh (Yorkshire) to 37.4209p/kWh (Merseyside and North Wales) (Octopus product data, Octopus Go). Round-trip efficiency: EcoFlow does not publish a figure for the STREAM, so we assume 90%. To deliver 5 kWh at the day rate you buy 5 / 0.9 = 5.556 kWh at the night rate, which costs 52.78p. Low: (5 kWh x 33.555p) - (5.556 kWh x 9.5p) = 167.775p - 52.778p = 114.997p a day x 365 = £419.74 a year. High: (5 kWh x 37.4209p) - (5.556 kWh x 9.5p) = 187.105p - 52.778p = 134.327p a day x 365 = £490.29 a year. That is about £1.15 to £1.34 a day. This is a ceiling, not a typical saving: it assumes one full 5 kWh cycle every day, all of it used at the day rate, so real savings will be lower. Your saving depends on your region, usage, and how much of the battery you use each day. 5 kWh capacity and expansion packs: EcoFlow UK STREAM AC 5000. Best-case payback on £2,499 fully installed is about 5.1 to 6.0 years (£2,499 / £490.29 = 5.1; £2,499 / £419.74 = 6.0). Check your region.

Compare it to interest on a savings account, not just payback years

Payback years is the usual way to judge a battery, but there is a fairer question: what interest would a savings account need to pay to match it? £2,499 spent on an electrician-wired EcoFlow STREAM is money that could sit in a savings account instead. Divide the yearly saving on your bill by what you paid for the installed battery, and you get a yearly return you can compare with a savings rate.

Yearly saving ÷ installed cost = equivalent interest rate.

If you saved this much a year	Installed cost	Equivalent interest rate
£200 a year	£2,499	about 8.0%
£300 a year	£2,499	about 12.0%
£400 a year	£2,499	about 16.0%

There is also a tax difference. A lower bill is money you do not spend, not interest paid to you, whereas savings interest can be taxable above your tax-free allowances (GOV.UK: Tax on savings interest).

Real savings depend on your tariff, your usage, and how much of the battery you use each day. Batteries also lose some capacity over time, so the yearly saving can drift down as the battery ages.

Habo installs an electrician-wired EcoFlow STREAM from £2,499. Habo will try to serve anyone who registers in an area where we have an electrician.

Join the install waitlist

Reduce the impact of price rises

A battery does not take you off the grid. Standing charges still apply, and anything the 5 kWh does not cover still pays the daytime rate. What it does is buy a chunk of every day's use at last night's cheap rate.

When daytime prices rise, the units already in the battery do not. That reduces the impact of unit-rate rises on the electricity you use each evening. If peak rises faster than overnight, the spread widens and the battery is worth more, not less.

Works with or without solar

Most battery companies assume you have solar panels. We don't. A 5 kWh battery still pays for itself through overnight charging either way.

☀️ I have solar

Store your free solar energy
Use it in the evening instead of selling back at 4p
Boost self-consumption from 30% to 80%
Still benefit from overnight tariff charging

🔌 I don't have solar

Charge overnight at 9.5p/kWh on Octopus Go 12M Fixed (source)
Power your home during the day
Save up to about £420 to £490 a year on 5 kWh, best case with a full daily cycle and an assumed 90% round-trip efficiency, so real savings will be lower
Hardwired in any suitable home. Not a plug-in kit

Questions you probably have

Really. The battery pays for itself through tariff arbitrage: charging when electricity is cheap (overnight) and discharging when it's expensive (daytime). Solar is a nice bonus if you have it, but it's not required.

Yes. The 5 kWh STREAM or AC 5000 is the starting box. Expansion packs stack on the same system if your usage grows. Join the waitlist for the base install first. We talk through pack options when we can book.

Every Habo Energy install is electrician-wired to your consumer unit under G98 and BS 7671. Fully installed from £2,499. Join the install waitlist and we contact you when we can book. This is not a plug-in battery. You cannot legally plug a battery into a UK socket and feed the house.

Any time-of-use tariff with cheap overnight rates works. Octopus Go (9.5p overnight on Octopus Go 12M Fixed, checked 10 October 2026) is a common choice. Economy 7 works too. Intelligent Octopus Go offers even cheaper rates but requires a compatible EV.

Best case about 5.1 to 6.0 years for a 5 kWh battery at £2,499 fully installed (£2,499 / £490.29 = 5.1; £2,499 / £419.74 = 6.0). That uses up to about £420 to £490 a year on Octopus Go, which assumes one full 5 kWh cycle every day and an assumed 90% round-trip efficiency, so real savings will be lower and payback longer (rates and sums). After that you keep the annual saving. EcoFlow lists a 10-year warranty for STREAM 5000, STREAM AC 5000 and the Expansion Battery 5000 (EcoFlow UK warranty policy).

It is a buffer, not independence. You still pay standing charges, and you still pay the daytime rate on anything 5 kWh does not cover. The units the battery shifts were bought overnight, so a jump in daytime prices hits those kWh less hard. If peak rises faster than overnight, the saving can grow.

A 5 kWh STREAM or AC 5000 all-in-one box (inverter in the unit), electrician-wired to the consumer unit (G98 / BS 7671). Fully installed from £2,499 at 0% VAT. Expansion packs are optional later.

Learn more

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Why I started Habo

Hi, I'm James. When I looked into home batteries, I found a minefield. Dozens of brands, confusing specs, compatibility questions, and hours of research just to figure out what would actually work for my house. I just wanted something that works, without becoming a battery expert first.

So I built Habo: a 5 kWh STREAM or AC 5000 all-in-one, electrician-wired to the consumer unit, pre-configured for UK cheap-overnight tariffs. Expansion packs if you need more later. No endless research. No plug-in shortcuts. Just a box that saves you money once it is booked and fitted.

– James, Founder