In the past I've used this forum several times to ask questions and I was surprised how quick my questions were answered. One topic "if it's possible to run an a/c from you batteries
" was quite hard to get answered. Since then I installed a 10.000 BTU airco unit from the dutch company The Climate Factory (TCF) in our Excess 11 catamaran
that runs off our Victron Lithium
bank (this is not in any way a sponsored post!). I thought I'd share my experience as this topic has come up several times. It may help others in the decision making process.
My Question some months ago was:
can you run an airconditioning from you (lithium) batteries
The idea was that when we would be (stuck) in a hot marina we could run the airco at night so we could sleep better
AND (much more important for this discussion) to run the airco when at anchor
- this is when the data becomes important
What we did:
How much did the airco cost:
- Installed a 10.000 BTU reverse cycle airco from The Climate Factory (TCF) in the owners hull of our Excess 11 catamaran.
- Our hull is approximately 11 by 2 meters when we leave the door the wet area open
- We had 900 Ah (3x 300 Ah Victron Smart Lithium) installed including a 5000 watt Victron Quattro as well as a Victron BMS and charge controllers to prevent the alternators of our 29 hp Yanmar engines to go up in smoke.
- Installed 990 watts of rigid solar panels on the davits
- Installed 12x 111 watts (=1332 watts) of walkable flexible solar panels on the roof. We opted for Sunbeam Tough Solar panels. So far these have been superb and we walk over them daily when we pack the mainsail.
€1500 for the 10.000 BTU version including 21% VAT as we installed it ourselves (6 hours of work).
Although the manual could be slightly improved (I have to call them once during the installation). The installation
is quite easy and took around 6 hours. It all depends whether you have a spare throughole you can use for the water
inlet. We used an existing sink outlet as the outlet for the airco.
How much power does it consume
This was our biggest unknown. At the dock
you can of course plug
in your shore power
and the thing will run. We now ran it for several nights and here are the numbers.
- Location: Ibiza and mainland Spain
- Outside temperature: 30 celsius
- Water temperature: 26 celsius
- Set temperature on control unit: 22 celsius
- Run time: around 23:00 until 08:00
- The compressors consumes around 500 watt when running
- The fan consumes between 150 watt and 300 watt depending on the set level (1-5)
- So when the unit is running at full cooling capacity it consumes around 800 watts (in cool mode)
- For heating mode; you can add around 150 watts
Key is the cycle time
; how much minutes per hour does the compressor
We've put a Voltcraft energy meter between the airco unit and the power outlet it uses; so now we know
Here's an image of the power consumption
On average the unit uses around 380 watts per hour when you want to sleep at 22 degrees celsius in a 30 degrees celsius environment
. This adds up to around 2660 watt hour assuming you run it for 7 hours a night. You can see from the screenshots (note the time are off due to timezones issues) the consumption
is much higher in the first couple of hours and gradually decreases.
As mentioned we have around 11.000 watt hour of lithium
(900 Ah @ 12 volt). Every day our batteries
are at 100% state of charge via the solar panels
. We can thus run the airco every night if we want to. And that's pretty awesome.
Some final remarks:
- If TCF is reading this; it would be great if the unit would come with a timer option like our Caframo Sirocco II fans. The Voltcraft energy meter could switch off the unit at a certain time but I don't think the unit would appreciate it.
- After seeing the video from Gone with the Wynns and others about the surge spike and corresponding solution: installing a softstart I was worried turning on the unit would blow our fuses. TCF let me know that the start up spike is around 2-3x the usage. So that would be around 2400 watts (3* 800 watt). With an 5000 watt inverter (that can handle up to 12.000 watt of surge) this isn't an issue at all. We can even cook on induction and boil water and still switch on the airco...
I think it's feasible to run a 10.000 btu airco (which is way too much for 1 owners hull) daily from your batteries as long as you have around 7000 watt hour of lithium (so you only use ±50% of your capacity for the a/c) and enough solar (around 1200 watts) and a >=3000 watt inverter