Editor note: Happy New Year all! As promised here’s a deeper dive into the electrical refit I took on this past month. The regular Sunday morning newsletter will go out as its normal time.

There’s a moment in every long-term cruising plan when you stop thinking in seasons and start thinking in years. Standing at the beginning of that horizon, I knew this was one of those moments.

The decision to upgrade the electrical system on Celtic Cross wasn’t driven by novelty or headline numbers. It was driven by durability, clarity, and accountability.

I didn’t want a system built from mixed and matched components—different vendors, overlapping responsibilities, and gray areas where no one quite owns the outcome. When something fails offshore or far from a service dock, the last thing you want is to be arbitrating between manufacturers. One ecosystem. One architecture. One set of assumptions.

Lithium wasn’t an upgrade for comfort alone. It was a decision about longevity.

• Four Victron 25.6V / 200Ah NG LiFePO₄ batteries
• Total capacity: 800Ah at 24 volts
• Designed for daily cycling, high discharge rates, and long service life
• Integrated into an external BMS architecture rather than internal drop-in protection

• Victron Lynx Smart BMS, 1000A NG
• Dual Victron Lynx Distributors for fused DC distribution
• 500A shunt for accurate current and state-of-charge measurement
• Centralized system protection and controlled shutdown capability

• Victron Quattro 24/8000 inverter/charger
– 8000 watts of inverter capacity
– Supports air conditioning, cooktop, and water heater off-grid
• Existing Victron Multiplus 24/3000 retained and integrated
• Dedicated Victron 24V to 1200W inverter for isolated 120V outlet

• Engine alternator converted from internal to external regulation
• Wakespeed WS500 Pro alternator regulator
– Lithium-aware charging profiles
– Temperature sensing and current limiting
– Direct communication with Victron system
• Victron Orion-Tr Smart 24/12 DC-DC charger
– Charges engine start battery from lithium house bank
• MPPT solar charge controllers reconfigured for lithium profiles

• Victron Cerbo GX MK2 system controller
• Victron GX Touch 70 display
• Centralized monitoring, alarms, configuration, and diagnostics
• Enables accurate observability instead of inferred system behavior

• Marinco 50A shore power inlet and cabling
• New inlet breakers and protection
• All main AC wiring upsized to correct AWG for inverter-supported loads
• AC distribution reconfigured to allow additional loads on inverter

• 4/0 AWG marine-grade battery cable (red and black)
• 2/0 AWG marine-grade battery cable
• 4 AWG and 8 AWG DC wiring
• Bus bars, fuses, resettable breakers, selector switches
• Terminal blocks, enclosures, proper lugs, heat shrink, and strain relief
• Full rework of DC backbone to support lithium current levels safely

• Bow thruster placed under relay control
• Audible alarm to warn of current levels approaching BMS limits
• Blue Sea battery switches and circuit breakers throughout the system
• Designed to prevent sudden BMS shutdown during critical maneuvers

• Removal and refurbishment of alternator for external regulation
• Full system integration rather than component replacement
• Configuration, testing, and commissioning as a unified architecture

Selecting the installer mattered as much as selecting the equipment.

I found Maz Ocean the way I approach most consequential decisions: careful searching, filtering reviews, looking for consistency rather than hype.

What ultimately sealed the decision came from an unexpected place. I’d spoken with a representative from MG Battery Corporation, who works closely with Victron—close enough that MG manufactures the NG lithium batteries Victron brands and sells. During that conversation, he asked who my installer was going to be. When I said Maz Ocean, he didn’t hesitate.

He told me he couldn’t recommend a better installer.

That kind of endorsement carries weight—especially coming from someone who sees installations succeed and fail across hundreds of boats.

Maz Ocean was not the least expensive option. I could have found cheaper. But what I received instead was professionalism, disciplined execution, and technicians who are not just trained, but genuinely smart. They understand systems, not just components. When something didn’t behave the way it should, they worked the problem instead of working around it.

That matters with lithium. High-current systems don’t forgive guesswork. Offshore boats don’t benefit from shortcuts taken at the dock.

In the end, the cost difference faded quickly. The confidence didn’t.

For a guy and his boat standing at the beginning of a long cruising life, this felt like the right way to start: one system, one standard, and a foundation built to last.