Lighting is the system people most often over-plan for and the one that matters least to your battery. Here is what ours actually pulls, measured rather than estimated.
The Numbers#
We run six dimmable 12V LEDs, split across two switches: one switch runs four lights, the other runs two.
| What is on | Draw |
|---|---|
| All six, full brightness | 13W |
| The four-light circuit alone | 9W |
| The two-light circuit alone | 4–5W |
| All six, dimmed as low as they go | under 5W |
Measured Read off our BLUETTI’s own display, in our van, on our lights.
Those numbers are internally consistent, which is the first thing worth checking in anyone’s measurements: 9W plus 4–5W lands at 13–14W, and the full-brightness reading of 13W sits at the bottom of that range. Per light it works out to about 2.25W on both circuits. Estimate
The Dimmer Is the Real Finding#
The part that surprised us was not the full-brightness number. It was the bottom of the range.
All six lights dimmed as low as they go come in under 5 watts. That is at least a 62% cut from the 13W figure, for a setting we use most evenings anyway because it is the one that makes a van feel like a home instead of a waiting room.
This is the number that turns a $15 dimmer from a nicety into the single best-value part of a lighting circuit. We already argue for spending it in the lighting guide, where the advice was “spend the $15 the first time” and the reasoning was comfort. It turns out the power case is just as strong.
What This Means for Sizing#
Multiply by the hours you actually run them:
| Hours per evening | At full brightness (13W) | Dimmed (under 5W) |
|---|---|---|
| 3 | 39Wh | under 15Wh |
| 5 | 65Wh | under 25Wh |
| 8 | 104Wh | under 40Wh |
Estimate Straight arithmetic from the measured wattages above.
Put that next to a compressor fridge, which on our own measurements runs 20 to 25Wh per hour in Florida heat, and the comparison is stark: our fridge can use more power in three hours than our lights use all evening.
Why Lighting Is Not Your Problem#
In eight years of full-time van life, lighting has never been the load that ran us short. Not once. The things that have: the fridge in a humid summer, and charging faster than the sun could refill.
So if you are sizing a system and you are agonising over lighting, you are optimising the wrong end of the spreadsheet. Pick warm LEDs, put them on a dimmer, and spend the attention on the fridge and the recharge path instead. If you want to check that against your own loads, the power calculator will do the arithmetic for you.
How This Was Measured#
Worth saying plainly, because the method decides how much the numbers are worth.
These readings came off the BLUETTI’s own display, not a clamp meter or an inline shunt. That is a real measurement of a real van, and it is also a station meter with limited resolution at the bottom of its range. Which is exactly why the dimmed figure is written as “under 5W” rather than a precise decimal we cannot stand behind.
If you need lab precision, this is not that. If you need to know whether lighting will break your power budget, it will not, and these numbers are more than good enough to prove it.