Is DIY Off-Grid Advisor free to use?

Yes. The Scout plan is completely free — no credit card required. You can create builds, run the load calculator, use all the standalone tools, and join the community at no cost.

What off-grid systems does it support?

DIY Off-Grid Advisor supports vans, caravans, RVs, 4WDs, boats, cabins, sheds, and remote properties. It handles 12V, 24V, and 48V systems.

How does the Component Wizard work?

You enter your loads (appliances and usage hours), your location (for real sun hours), and your system type. The wizard then recommends the right battery bank, solar panels, MPPT controller, inverter, and DC-DC charger — all sized for your exact setup. It also generates a wiring diagram and PDF report.

Do I need electrical experience to use it?

No. The platform includes a full beginner-friendly knowledge base — Electrical 101, How-To guides, Troubleshooting, and a Glossary — so you can learn as you build. The tools are designed to guide you step by step.

DIY Off-Grid Advisor

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Size My System

How to use this page

Voltage Upgrade Calculator

Everything that changes when you go from 12V to 24V

See exactly what changes when you upgrade from 12V to 24V — batteries, cables, fuses, inverter, MPPT, DC-DC charger, and DC loads. Enter your current setup and get a complete component-by-component breakdown.

How to use it

Set your voltages

Choose your current voltage (12V) and the target voltage (24V). The tool calculates the impact across every part of your system.

Enter inverter size

Enter your current or planned inverter wattage. This drives the cable and fuse sizing — doubling voltage halves the current, so cables can be significantly smaller.

Enter battery details

Set your battery chemistry, Ah per battery, and quantity. The tool calculates how to rewire them in series for the new voltage while maintaining the same Wh capacity.

Set cable run length

Enter the one-way distance from battery to inverter. Used to calculate the voltage drop improvement at the new voltage.

Expand each section

Click each section (Battery, Inverter, Cables, MPPT, DC-DC, Loads, Safety) to see exactly what needs to change and what you can keep.

Tips & things to know

All 12V DC loads (fridge, lights, USB) will be destroyed if connected directly to a 24V system. Use a DC-DC step-down converter or replace with 24V-rated equivalents.

Doubling voltage halves the current — smaller cables, less heat, better efficiency, and a higher practical inverter ceiling (up to 6kW at 24V vs 3kW at 12V).

Your DC-DC charger (alternator) must be replaced with a 12V-to-24V model. A 12V-to-12V unit won't work in a 24V system.

Your MPPT charger may support multiple output voltages (12/24V auto-detect) — check the spec sheet before assuming you need a new one.

Lithium Upgrade Calculator

Cable & Fuse Checker

Site Guide

View full site guide

DIY Off-Grid Advisor

HomeToolsVoltage Upgrade Calculator

Voltage Upgrade Calculator

Thinking about upgrading from 12V to 24V? Enter your current setup and see exactly what changes — batteries, cables, fuses, inverter, MPPT, and more.

Free ToolNo signup needed

System Voltage

Current voltage

Upgrade to

Inverter Size

Inverter continuous watts

Enter your current or planned inverter size

At 12V

196A

At 24V

98A

Current Battery Bank

Chemistry

Ah per battery

Number of batteries

Total bank capacity

4800Wh

2 × 200Ah @ 12V

Battery-to-Inverter Cable Run

m (one way)

One-way distance from battery to inverter

Upgrade Summary: 12V → 24V

50%

less current draw

196A → 98A

0.1% → 0%

voltage drop

at 2m cable run

4800Wh

bank capacity

maintained after upgrade

Current (12V)

2 × 200Ah @ 12V

4800Wh total

Wired in parallel

After upgrade (24V)

4 × 200Ah @ 12V

4800Wh total (same)

Wired in series (2 batteries per string)

How to wire 4 batteries for 24V

Connect batteries in series: positive terminal of battery 1 to negative terminal of battery 2. The remaining positive and negative terminals connect to your system.

Critical: All batteries in a series string must be identical — same brand, model, age, and state of charge. Mismatched batteries in series will cause premature failure and potential safety hazards.

AGM / Lead-Acid series wiring notes

Use identical batteries — same brand, model, capacity, and ideally same age

Equalise charge all batteries before wiring in series

AGM batteries in series can develop imbalance over time — periodic equalisation charging is recommended

Consider upgrading to LiFePO4 at the same time — lithium handles series wiring much better with built-in BMS balancing

Complete Upgrade Checklist

New 24V inverter (or verify existing inverter supports 24V input)

Battery bank rewired in series for 24V (4 batteries)

Main fuse upgraded to 125A Class T (lithium) or ANL (AGM)

Main battery cables: 2 AWG / 35mm²

MPPT charger verified or replaced for 24V battery output

DC-DC charger replaced with 12V-to-24V model

12V DC loads connected via 24V-to-12V step-down converter

Battery isolator switch rated for 24V DC

All connections labelled with voltage and polarity

System tested at no-load before connecting appliances

Lithium Upgrade Calculator

Upgrading from AGM to LiFePO4? See what changes.

Cable & Fuse Checker

Get exact cable size and fuse rating for any DC run.

Found an error on this page?

Report a calculation error, broken feature, or unexpected result

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