BBK26: Powering the Expedition!

Apr 15, 2026

The Reality

Modern expeditions run on electrons as much as calories.

For Britain by Kayak 2026, I’m carrying a small set of essential devices — not for comfort, but for:

  • Navigation
  • Safety
  • Communication
  • Recording the journey

But every device adds a simple question:

How do I keep it all powered — reliably — for weeks on end?

This blog sets out:

  • What I’m taking
  • The power system behind it
  • What I learned on a recent mini-expedition in Asturias
  • And the simple charging strategy I’ll use around Britain

📱 The Devices

Core expedition electronics

  • Garmin GPSMAP 86i
    Primary navigation and tracking device with inReach satellite comms.

  • Garmin Fenix 7
    Activity tracking, backup navigation, and daily logging.

  • iPhone 15 Pro Max
    Charts, weather, comms, photos, and content capture.
    (Also the camera that took the photo here — which is why it’s missing from the shot.)

  • Shokz OpenSwim (Waterproof Bluetooth headphones with 4gb stored music) Not essential — but useful for morale on long solo days.

Supporting kit

  • Flextail mini-pump
  • Headtorch / tent light (also doubles as a small emergency battery)
  • Exposure Raw-Plus Marine Torch and Strobe

🔋 The Power Banks

What I’m carrying

  • RidgeMonkey Vault C-Smart Wireless 26950mAh
    Primary energy store (~100Wh class)

  • Flextail Zero (~10,000 mAh)
    Secondary / backup

  • Black Diamond lamp (~2,400 mAh equivalent)
    Small but useful final reserve

Why three?

Not about capacity — about resilience:

  • One fails → system still works
  • One gets wet → backup available
  • One runs low → buffer remains

Redundancy without over-complication

⚠️ What I Learned in Asturias

A short mini-expedition in northern Spain was a useful test.

On paper, the system worked.

In practice:

My Garmin barely charged overnight — despite being plugged in for hours.

The issue

  • Charging via USB-A → micro-USB
  • Garmin auto-powered when connected
  • Screen/backlight active
  • Net gain: ~5–10% over several hours

Meanwhile:

  • iPhone charged perfectly
  • Power bank had plenty of capacity

🔧 The Fix (Garmin-Specific)

This was the key learning.

The solution:

  • Use a USB data-blocker (charge-only adapter)
  • Place it between charger and cable
  • Prevents the Garmin seeing a “data connection”

Why this works

Without the data pins:

  • The Garmin is less likely to boot fully
  • It stays in a low-power charging state
  • More of the incoming energy goes into the battery

Plus:

  • Short, good-quality cable
  • Turn the unit fully off before charging

Result: reliable, predictable charging

This is now a fixed part of the system.

🔌 Shore Power: The Charging System

Charger

  • Anker 140W 4-Port GaN Charger

This allows me to charge:

  • Power bank
  • Phone
  • Garmin
  • Other devices

All from one socket

How I’ll use it

Short stop (≈1 hour)

Priority:

  1. Phone
  2. Garmin
  3. Power bank

Fast gains first.

Overnight

Everything plugged in:

  • USB-C → power bank
  • USB-C → phone
  • USB-A → Garmin (via data blocker)
  • Spare → other devices

☀️ Why I’m NOT Using Solar

This is the question everyone asks.

Short answer:

Because it adds complexity for very little real-world gain.

The reality of solar on a kayak:

  • UK weather = inconsistent sunlight
  • Panels need constant angle adjustment
  • Deck mounting = awkward and vulnerable
  • Output often low and unpredictable

In practice:

You rarely get:

  • Stable output
  • Efficient charging
  • Meaningful energy gain day-to-day

The trade-off

Solar adds:

  • Cost
  • Weight
  • Deck clutter
  • Another failure point

In return for:

  • Marginal, inconsistent charging

My approach instead

  • Carry enough stored energy
  • Recharge opportunistically (cafés, campsites, harbours)
  • Keep the system simple and robust

Reliable beats theoretical

🔋 Off-Grid Strategy

Daily

  • Phone + Garmin topped up from main power bank
  • Backup bank untouched unless needed

Capacity reality

From testing:

  • Garmin: ~30% per day
  • iPhone: ~30–40% per day

What that means

~5–7 days autonomy without mains power (conservative)

More in good conditions.

🧠 The System Approach

This isn’t about gadgets.

It’s about a system that works when you’re:

  • Tired
  • Wet
  • Cold
  • Making decisions alone

So the rules are simple:

  • Prioritise critical devices
  • Charge when you can, not when you need to
  • Build in redundancy
  • Keep it simple

🧭 Final Thought

Power is now part of expedition planning — like food and water.

Ignore it, and it will trip you up.

Overcomplicate it, and it becomes fragile.

Get it right, and it disappears into the background — exactly where it should be.

If you’re planning something similar:

Test your system in the field — not at home.

That’s where the real answers are.