Why 12 V DC appliances save 12–18 % vs inverter-fed AC

When a portable power station runs an AC appliance, the energy goes through three conversion steps: battery DC → inverter AC → appliance internal AC-DC step-down → motor or compressor. Each step loses energy as heat. For a Watiqa DC appliance plugged direct into the Sirius 12 V regulated DC port, the chain collapses to one step: battery DC → motor or compressor.

The conversion chain costs

| Step | Typical loss |

|---|---|

| Battery DC → 230 V AC inverter | 8–12 % |

| AC → appliance internal DC | 3–6 % |

| **Total round-trip loss** | **12–18 %** |

For a 2 kWh Sirius running an AC fan for 40 hours, you lose 240–360 Wh to conversion — enough energy to run the fan for an additional 5–9 hours.

Where the savings show up

Watiqa Fan (15 W brushless DC) running off Sirius 1K (1,000 Wh):

• AC equivalent: 1,000 ÷ 15 ÷ 1.15 conversion ≈ **58 hours runtime**
• DC native: 1,000 ÷ 15 ≈ **66 hours runtime**

That's an extra 8 hours — meaningful overnight in a hot summer.

Where it doesn't matter

Pure-resistive AC loads (toaster, kettle, soldering iron) run nearly the same on AC or DC because they don't have an internal step-down. The inverter loss is real (8–12 %) but no second conversion adds on top. For these loads the convenience of standard AC sockets wins.

When to spec DC native

Always spec DC native for:

• **Brushless motors** (fans, mini-fridge compressors) — biggest savings, best motor efficiency
• **LED lighting** — LEDs are inherently DC; an AC LED bulb has an internal AC-DC driver that fails before the LED does
• **Phone & laptop charging** — USB-C is already DC

Pairing with Sirius

Sirius outputs regulated 12 V DC at 10 A from an XT30 socket; each Watiqa appliance ships with the matching XT30 cable. The Sirius's internal DC-DC converter is more efficient than any AC inverter at small loads (<200 W), making the savings even larger for low-power devices like the Watiqa Fan and Lamp.

A note on cable length

DC voltage drop becomes meaningful past 5 m of cable run. Watiqa cables are 2 m by default; for longer runs, NURION supplies AWG 14 extension cables with the matching XT30 connectors that keep voltage drop under 3 %.