Hi Cat- Keys
I hope my answers helps you to take the best decision in your investment, based on my experience as engineer
working not only at multinational generators company, but also at green energy systems and now in the marine
hobbies, so I can give you my best advice on different options:
Below my point of view for each question:
Regarding your energy use about 285Ah per day on the hook and 325 underway with radar autopilot
Let’s talk about an average range around 300Ah per day.
First, we are going to determine the energy consumption
adding an air conditioner with an inverter
and the better option choosing the new technology on 12volts DC air conditioners Low consumption
amps on the market:
• For your current
2 x 16,000Btu Cruise
air AC-powered system draws Arround 13 Amps each, But starting current says it is about 5 times normal running current for a typical motor
. Applying that formula to this brand, gives results (5x13=65 Amps) in the same scenario. Now lets convert this situation to an 12V DC supply with an inverter
+ adding the energy losses associated with the inverter About 8%:
o We have running current around 13 amps @115volts ac
o We now will have same 13 Amps x 9.58 times aprox. (converting to AC to DC 13 Amp x 9.58 times = 125Amps aprox.) + 8% losses = 134.5 amps (using inverter) and adding the information on the starting amps situation will be double: around 270Amps.
Now, lets analyze another brand on the market:
Regarding the Brand you mention: using a new 24v zero breeze 2300BTU rechargeable unit in our master berth only.
• This seems to be a good brand, good quality, but not for your needs. It is more to refresh an space like a cooling
fan than to recirculate and climatize a room. (low Capacity BTU).
Giving you my opinion and suggestions:
There is a brand recognized World wide on marine
air conditioners, Mabru Power Systems
. They have the most efficient air conditioner running directly from 12Volts DC with the lowest Amps draw.
For example: if you are going to replace your units 16K BTU you can easly choose the 12KBTU DC from Mabru Marine, and you will have the following energy consumption and almost same capacity and less noise
and they have an offer that the pump
comes included in the price
for those new DC units:
The SC12DC from Mabru, Draw amps between 33 to 44 Amps, and you can run the unit direct from the battery. That means you will have around 44 Amps by Hour. So if you have for example just a battery bank of 500Amps, (500 ų 44 Ah = 11.3 hours for each Mabru air conditoner) you will have a running time around 11 hours at full speed, during the day with the Sunny day, and also during the night you can reach more running time depending of the external temperature (lower temp = more running time on this DC air conditioner). This unit is an Inverter operation, that runs gradually increasing or decreasing the compressor
speed, so you will not have starting amp draw, that is amazing on this brand. The were working on their patent because by the moment are the only one in the world with this capacity with the lowest consumption working on 12V.
Regarding your most important question is that if you have to replace the Generator and associated operation costs by batteries and go green energy, definitely Yes.
The Contras of the Genset is that you will have:
cost and reservoirs weight.
• Every 200 hours maintenance
changes (dirty work).
• 115 Volts to then convert to 12V for final usage.
air: 16K BTU @ directly working on 115Vols:
• Draw amps 65 starting and then 13Amps.
o @12Volts DC increases to: 134.5 Amps (with starting amps around 270 Amps)
Mabru Marine: 12K BTU @ 12Volts DC:
• @12 Volts DC Draw amps 33-44 Amps
• Starting Amps N/A (starting amps Not applicable)
Instead Spend $19,100 on the Generator + maintenance
cost associated you mentioned ($15,600). Just for have fresh air confort for just only use 3 or 4 months a year and then only at night ☹. Not a good deal.
What U will be consuming is around 325Amps a day + your air DC air conditioner, you just have to make the most of your excellent and impressive renewable energy system.
You can reach Lithium batteries + The Mabru Air conditions SC12DC x 2 units with less that have cost than buy a new generator + inverter to move those big and low efficiency Cruise air conditioners.
250 amps Lithium batteries with 2 years warranty around $2300 each
SC12DC 12volts air conditioners around $5500 each. (1.5 amps -12volts low noise pump
And you will have almost all your system working directly 12Volts dc.
You can see a youtube videos regarding the difference between the two brands. Also the Mabru air conditioners capacity of condense the humidity of the air is better, which translates into dry air = comfort)
Mabru vs Cruise air Dometic on this youtube video:
I hope my explanation on this scenario helps you to have better idea on what you need.