A trailer gives you room for a real setup — and a real power problem if you guess it. Wattonomy sizes the battery and inverter to start your espresso machine and carry a full day, then draws the wiring and lists the parts.
A real Wattonomy output — a towable coffee trailer
System
24 V
Battery
10.24 kWh
Solar
1200 W
Inverter
MP-II 24/5000 12
SmartSolar 100/501×
200W solar panel6×
Battery → inverter cable7×
Battery → inverter fuse1×
Wire & fuse sizes follow ABYC E-11 — each conductor carries its fuse and stays under a 3% voltage drop.
Built to ABYC standards
Gauge · fuse · volt-drop sized
Every spec sourced
More space tempts more machines than a guessed system can start.
A trailer often means a bigger espresso machine, a proper fridge and a blender — and their combined start-up surge is what flattens an undersized inverter. Wattonomy sizes the inverter for the surge, the bank for the day, and every cable to carry its fuse, to ABYC E-11.
What a coffee trailer has to get right.
Room for a real setup — sized so it actually starts and lasts.
Trading-day energy
Espresso, grinder, fridge, lights and POS — summed as real Wh for your day.
Inverter for surge
Sized to start your heaviest machine, with headroom so it never trips at the rush.
Battery + charging
LiFePO4 sized to the day, topped by solar and charge-while-you-tow.
Cables, fuses & circuits
Every gauge and fuse matched to its load, with the espresso machine on its own dedicated circuit.
What you walk away with — free
A validated system sized to your equipment — not a one-size kit
A clean wiring diagram with every cable gauge and fuse spelled out
Cable & fuse sizing with the voltage-drop checked for your run lengths
A shoppable parts list, each line traceable to ABYC or Victron specs
Building it for real? Unlock the build binder.
Free gets you a safe, correctly-sized design. The build binder gets you the documents to build it right — and prove it's right.
Printable wiring diagram, yours to keep & tape inside the trailer
Full parts list, every line sourced
The volt-drop & fusing calculation trail — the "why" behind every spec
The build binder is a one-time unlock — no subscription, no auto-renew.
Questions
How big a battery and inverter for a coffee trailer?
Enter your machines and the tool sizes both to your real loads and the start-up surge — a trailer often lands a little larger than a cart because the kit is bigger.
Two-group machine on a trailer — battery or shore power?
A two-group espresso machine is a 240V load; the tool flags it as a split-phase build and points you to an electrician, rather than pretending a single 120V inverter will start it.
Can I tow-charge it?
Yes — the tool can size alternator/DC-DC charging so towing tops the bank up between pitches, on top of solar.
Do I need an account?
No. Design the whole system free, no email required. Accounts are only for saving builds or the printable build binder.
Is this just trying to sell me a kit?
No. The parts list is vendor-neutral and standards-referenced — buy the components anywhere. We make the design, not the markup.
The standards we build to
Plain version: these are the recognized rulebooks your design is sized against, so the numbers hold up to a surveyor, an inspector or an insurer.
ABYC E-11The US standard for AC & DC wiring on boats — what a surveyor or insurer actually checks.
Wattonomy applies these standards in its calculations. It is not certified, sponsored or endorsed by ABYC, ISO, NFPA or Victron — it sizes your design to meet what they require, and shows the working.
Sized and checked to ABYC E-11. Last reviewed June 2026 — see the full methodology for the exact rules behind every number and how each design is validated.
Built by anABYC Certified Master Technician