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Solwex

Battery storage

Solar with battery storage: more of your own power, after sunset too

Without storage a household typically uses only about a third of its solar power itself. A well-sized battery shifts the midday surplus into the evening. We plan the battery together with the system and size it to your consumption rather than to the largest model in the catalogue.

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  • Sized to consumption and system size
  • Planned with a new system or retrofitted to an existing one
  • Optional backup power during grid outages
  • Lithium iron phosphate (LFP) technology

Solar calculator

What would a solar system cost you?

Size, price range, savings and payback for your roof – calculated in two minutes with irradiation data for your location. Free and non-binding.

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How large should the battery be?

A proven rule of thumb for homes: about 1 kWh of usable capacity per 1,000 kWh of annual consumption, and no more than roughly 1 to 1.5 kWh per kWp of solar. A household with 4,500 kWh consumption and a 10 kWp system ends up at about 5 to 8 kWh.

Bigger is not automatically better: an oversized battery rarely fills in winter and rarely empties on summer evenings. With a heat pump or an electric car the picture changes, and a closer look at the load profile pays off.

Emergency power, backup and retrofitting

Many batteries offer an emergency socket that powers individual devices during an outage. A backup system supplies the whole house or selected circuits and needs a grid disconnection in the meter cabinet.

Existing systems can usually be retrofitted, typically with an AC-coupled battery and its own inverter. For new systems a hybrid inverter (DC coupling) is often the more efficient option.

How your project runs

  1. 1

    Enquiry

    You describe the building, roof area and goal — via the form or by email.

  2. 2

    Assessment

    We review the roof, structure and access from photos, plans or on site.

  3. 3

    Quote

    You receive a written quote with a clearly defined scope of work.

  4. 4

    Installation

    Our crew installs the substructure, modules and cabling.

  5. 5

    Handover

    Commissioning, photo documentation and a walkthrough of your system.

Frequently asked questions

The questions we are asked most often before a project starts.

How much self-consumption can I reach with a battery?

Without storage, households typically use about 25 to 35% of their solar power themselves. With a well-sized battery this often rises to 50 to 70%, depending on when you use power, system size and battery capacity.

Can a battery be added to an existing solar system?

In most cases yes, usually as an AC-coupled battery with its own battery inverter that works independently of the existing solar inverter. We check inverter, meter cabinet and installation space beforehand.

Related services

Solar for private homes

A PV system sized to your consumption and roof, installed on tiled, metal or flat roofs — with storage and roof renovation if needed.

Commercial solar

Solar for halls, offices and production buildings: daytime self-consumption, east-west on flat roofs, installation while you keep working.

Solar maintenance and repair

Regular inspection, cleaning when needed and fast fault finding — so your system keeps delivering the expected yield.

Get your battery sized properly

Tell us your annual consumption, system size (if you have one) and whether backup power matters. We will suggest a suitable size and a no-obligation quote.

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