What This Calculator Does
This off-grid system cost calculator gives you a price range for a solar and battery system before you ask anyone for a quote.
It shows three ways to get there, side by side.
DIY means you buy every part and fit it yourself, with a battery built from loose cells. An Off-shelf kit uses ready-made brand battery modules: you fit it, an electrician connects it. Professional means an installer does the whole job.
It's like building a lego set from loose bricks, buying the boxed set, or paying someone to build it for you.
How To Use This Calculator
- In Number of panels, type how many panels you want. The small line below shows the total size in kWp.
- In Panel wattage, pick the watts per panel. 445 W is a normal size today.
- In Mounting type, pick tiled roof, flat roof or ground mount. Ground-mount frames have no reliable price per panel, so the calculator leaves them out and says so.
- In Battery storage, type the usable battery size in kWh. The battery size calculator helps you choose.
- In Inverter phases, pick single or three phase.
- Tick the boxes that apply: a grid connection as well, parts you already own, a needed upgrade to a three-phase grid connection, or an inspection for the DIY path.
- Read the three cards. Each lists its parts, labour and extras, with a low and high total.
The Formula, In Plain Words
Every part has a low and a high price in a built-in table, including VAT. The calculator multiplies per-panel prices by your panel count and battery prices by your kWh.
The MPPT solar charge controller is priced per kWp, because a Victron inverter-charger has no solar input of its own. It never goes below €197, the smallest Victron SmartSolar that takes a normal 48 V panel string. The low end assumes a hybrid inverter with a built-in MPPT instead, which costs about €67 more than the cheapest inverter-charger. Already have panels? Then the controller is left out. Then it adds the fixed items, like the inverter-charger and the cables, fuses and monitoring. A grid energy meter is only added when you tick the grid connection.
DIY and the kit use the same panels, charge controller, mounting, inverter and cables. DIY builds the battery from loose cells, at about €115 to €157 per kWh. The kit uses brand modules at about €303 to €508 per kWh, and adds an electrician for 4 to 8 hours.
The professional card works like an installer quote. Solar costs €0.82 to €1.28 per watt, fitted, and a home battery €400 to €700 per kWh, installed. Those prices include the installer's own inverter, charge controller and labour.
All lows are added for the low total, and all highs for the high total. Prices come from Dutch shops, installers and grid operators, checked in October 2026.
A Worked Example
Take the starting values: 12 panels of 445 W, which is 5.34 kWp, on a tiled roof, a 10 kWh battery, single phase, off-grid, with an inspection.
DIY comes out at €4,563 to €6,863. The off-shelf kit lands at €6,015 to €10,614. Professional is €8,379 to €13,835. All incl. VAT.
The charge controller adds €67 (a hybrid inverter) to €614 (5.34 × €115 for a separate SmartSolar) to DIY and the kit. Tick the grid connection and both go up another €242 for the grid energy meter.
The biggest jump is the battery. DIY cells cost €1,150 to €1,573 for 10 kWh, brand modules €3,025 to €5,082, and an installed home battery €4,000 to €7,000.
What To Watch Out For
These are ranges to set expectations, not quotes. Prices change fast.
All prices include Dutch VAT. Panels with their inverter, mounting, cables and installation on or next to a home pay 0% VAT, so those prices are the same with or without it. The battery, the monitoring parts, the electrician, the inspection and the grid fees include 21%.
The professional prices come from grid-connected Dutch installs. We found no published prices for turnkey off-grid systems, so expect a quote above that card.
The table is built for the Netherlands. Prices, labour and grid fees differ elsewhere. Some extras only show up on a real site: a long cable run, a fuse box upgrade, or scaffolding.
For the bigger picture, read about the costs of going off-grid. Once you have a price, the solar payback calculator shows when it earns itself back.
Hard Words
| Term | What it means |
|---|---|
| kWp | Kilowatt-peak, the total power of all your panels in perfect test sunlight. |
| Inverter-charger | The box that turns battery power into normal home power and charges the battery. |
| MPPT charge controller | The box that takes power from the panels and charges the battery with it, getting the most out of the panels. |
| Mounting | The rails, clamps or frames that hold panels on a roof or the ground. |
| Three-phase | A grid connection with three power lines instead of one, used for bigger homes and loads. |
| VAT | Value-added tax, the sales tax added to prices in Europe. |
| SCIOS inspection | A Dutch safety check of an electrical installation by a certified company. |
Common Questions
How much does an off-grid solar system cost?
It depends on size, parts and who installs it. In this calculator, a 5.34 kWp system with a 10 kWh battery ranges from about €4,563 for a DIY build to about €13,835 for an installer, incl. VAT, using Dutch prices from October 2026. For a true off-grid install, an installer will likely quote more.
Is it cheaper to install solar and a battery yourself?
Usually yes, by thousands of euros, because you skip labour and can build the battery from loose cells. In the starting example, DIY costs about half of the professional price. But you need time, tools and skill, and you carry the risk. Many people pay for an inspection of the finished system.
What is the most expensive part of a solar battery system?
Often the battery. In this calculator, 10 kWh of brand battery modules costs €3,025 to €5,082, more than the panels for a 5 kWp system. A DIY battery from loose cells costs €1,150 to €1,573 for the same size, but you build and wire the pack yourself.
Are these prices with or without VAT?
With VAT. In the Netherlands, panels, their inverter and their installation on or next to a home pay 0% VAT, so those prices are the same either way. The battery, monitoring parts, labour, inspection and grid fees include 21%. Prices for panels and batteries change quickly, so use the result to set expectations before you ask for real quotes.
Do I need a three-phase connection for solar?
Not always. Many homes run a solar and battery system on a single phase. Larger systems, or homes with heavy loads like heat pumps and car chargers, may need three phases. In the Netherlands an upgrade costs a grid operator fee plus electrician work, which this calculator puts at €859 to €1,269, incl. VAT.