Battery Powered Air Conditioning 

For years we have been hearing from Boat Owners that they would like to run appliances including Air Conditioning powered from the electrical system. Previously up to now the answer has been NO, you don’t have enough power for that, so you will need a Generator if you’re lying at Anchor. 

But now things are changing. This last year we have been involved with an increasing number of electrical upgrades that takes advantage of the latest in mobile power technology. We have been seeing this trend in the Camper Van market for a while.

Recent Electrical upgrade projects PKYS Inc 

These projects include a Fountain Pajot 44, Lagoon 380 and a Jeanneau 54.  With large space for Solar panels and large battery banks we have the basis of a powerful onboard electrical system.  In these cases of the cats, the panel wattage is around 2,000 watts and the battery capacity 1,000 AH of lithium This ratio of twice as much solar to battery leads to a balanced system.   

 The space needed for 1,000 AH of Lithium batteries is far less than the equivalent Lead Acid bank. It's probably around 40% of the space. Plus the available AH's are double due to Lead acid batteries need to recharge at 50% State of Charge SoC. 

The feedback we hear from the Owners of these projects is that they are unanimous in the pleasure they have of keeping cool in silence, which is very important to them. They also save fuel.

Lithium Batteries 

The latest Lithium-iron-phosphate (LiFePO4) batteries are the safest of the mainstream li-ion battery and are substantially smaller and lighter with a very high energy density. This energy density allows for large AH battery banks to store energy. Stored energy means we can use that energy for things like A/C. With 1000AH hours of lithium batteries we can handle a lot of loads. 

One big advantage of Lithium batteries is the higher change rates, so when you are motoring for example, you can quickly get amps into the batteries. AGM will only accept smaller charge amps and have complicated charge profiles. Not only that but we can use more far than the 50% capacity of Lead Acid. So, these batteries are a game-changer in energy storage

PKYS Inc has a Demo system in our office, pictured below. The demo system is for mobile applications either Vehicle or Marine and which has the same components and works the same way as the Catamarans projects. The system makes it easy to see how much space is needed and how each of the components connect to each other. Very useful for planning, The system has one 200AH battery which can be expanded to 5 for a total of 1000AH.

The components of the Demo system are; 

200AH lithium battery expandable to 1000 AH 

Multiplus 12/3000 watt inverter charger  

BMS battery management system for Lithium batteries  

DC DC charger for handing alternator input  

Battery protects  

Switching gear  

AC and DC distribution panels  

Solar Controller  

Cerbo GX and Touch 50 screen 


Inputs into the system include Solar, Shore Power, Engine Alternator and battery. 

The Multiplus is programmed to take each of the inputs and distribute them as needed, The touch 50 screen shows you how that distribution is happening in real time.

The Touch 50 screen 

Wow your friends with system performance 

The Touch 50 screen is your guide to the systems data 

Watts from Shore Power, Solar and Alternator inputs 

Power distributed to AC and DC loads

Add Comment