Home Battery Savings in South Wales

Octopus Go rates in South Wales

On the current Octopus Go 12-month fixed tariff (GO-FIX-12M-26-09-29, region K, checked 10 October 2026), households in South Wales pay 35.657p/kWh during the day and 9.5p/kWh overnight (00:30–05:30), with a standing charge of 54.36p/day. The off-peak rate is the same across all regions; the daytime rate varies.

This covers postcodes: CF, LD, NP, SA – including Cardiff, Swansea, Newport. Your distribution network operator is National Grid Electricity Distribution.

About South Wales

South Wales has a significant proportion of older terraced housing in the valley communities, many of which are solid-walled properties with higher-than-average heating demands. Welsh Government energy efficiency schemes are available alongside UK-wide programmes, and the region benefits from strong coastal wind resources.

According to MCS data, at least 3,788 certified home battery installations have been completed in the South Wales region since September 2023 – part of a nationwide surge in domestic battery uptake.

Your savings with a 5 kWh battery

The battery charges overnight at 9.5p and powers your home during the day, avoiding the 35.657p daytime rate. The saving is the difference between what the stored energy would have cost at the day rate and what it cost to charge overnight, allowing for charging losses.

Rates from the Octopus Energy API (product GO-FIX-12M-26-09-29, Octopus Go 12M Fixed, region K, direct debit, checked 10 October 2026). The 90% round-trip efficiency is our assumption, because EcoFlow does not publish one for the STREAM. This is a best case: one full cycle every day, with all of it used at the day rate. Real savings will be lower. Best-case payback on £2,499 fully installed is about 5.5 years. See how we worked it out.

How South Wales compares

The Octopus Go off-peak rate (9.5p) is the same everywhere, but the daytime rate varies by region – so regions with higher daytime rates see bigger savings. Figures below are best-case yearly savings for a 5 kWh battery, worked out the same way for each region (GO-FIX-12M-26-09-29, checked 10 October 2026).

What Habo Energy offers

One 5 kWh EcoFlow STREAM all-in-one box. Inverter in the unit. Electrician-wired to your consumer unit under G98 and BS 7671. From £2,499 fully installed at 0% VAT. This is not a plug-in battery. Plugging a battery into a UK socket and feeding the house is not legal.