Why? Wouldnt it use more power?

 

It is common for appliances like blenders, microwaves, TV, etc to be AC powered. I don't understand why you would want interior lights AC powered. The lights themselves are no problem finding AC versions, but you would need to run all new wiring for them, and LED lights use very little power. If you have the common Danfoss/Secop fridge compressor, they make a dual AC/DC controller for it that can use AC power whenever it is available.

If you really wanted to do this, it would probably be easier to keep what you have and use a DC power supply. It would be odd - you would power the inverter with the batteries, then power the equipment with the converter back to DC, but I guess we don't find it odd when we do this to charge our computers, phones, etc.

Mark

 

Agree with the points above and add that 12volts is a lot safer in close quarters like reading lights over berths, fans in the same location and submersible pumps and the like.
I have added a removable lithium powerpack including big inverter/super fast charger/ mppt solar controller and remote monitoring and control to my yacht which plugs into my shore power circuit whilst leaving the rest of my 12 volt AGM battery system in place.
It provides power to my 240volt (Australia) appliances, induction cooking and water heater without the need to alter all the usual yacht 12v systems including nav/sonar, lights, fans, bilge, water and sump pumps, compass light and I am sure others I haven’t remembered which would all be difficult to run on household power.
It also means I have two separate sources of power thus having a reserve system in the event of a failure. 🙂

 

Stick w/ 12v LED lighting.

 

I guess it all depends on how you want to use your boat. If the boat will spend all of its time connected to the dock, then converting all of the electrical systems from 12VDC to 120VAC could be useful. You could get by with smaller wire gauge for a similar load (keeping watts constant, 12 volt uses 10X the amperage of 120V). You would have to rewire everything to make this work.

However, if the boat leaves the dock, and you still want to use these appliances, then you really should stick with 12VDC. Most batteries are available in 6V or 12V, and, while you can use an inverter to generate 120VAC from 12VDC battery banks, you lose 15-25% of the power because of inverter inefficiency.

I have two appliances on my boat that work on 120VAC; the hot water heater, and the battery charger. Everything else on my boat runs on 12VDC.

 

Thank you all for your precious feedback. I need to rebuild the electrical system from scratch because the past owner manipulated it so profoundly that it can be fixed. So I thought having only one system in place could be more accessible. Otherwise, I need to cable the 12V for lighting in each cabin plus 220v/110V for a socket.

On top of this, as many of your said TV and other appliance are cheaper and better.
I will have a lifepo4 battery system with BMS; I need, in any case, a little more complex system.

For these reasons, I thought about this solution.

 

I have two concerns about your plan. 1) An inverter probably will make a lot of electrical noise that may interfere with our radios. You don't want to lose SSB communications while cruising. I had to turn off the 12V refrigeration using the SSB because it uses an inverter to bring in weather and to communicate. 2) An inverter will not be 100% efficient and very inefficient at low loads I fear that the efficiency may take an extra hit from AC appliances with bad power factors. For example, an AC motor has a lot of inductance where the current and voltage are not in phase. To illustrate further, a pure inductor drawing 10 A from 110 V AC consumes no power, 0 Watts. Your inverter would not like this. Use an inverter for occasional jobs such as for power tools. Leave it off most of the time. [ A thought: I have a 12V anchor windlass located 20' from the battery bank. I use "0" gauge wiring to handle the 100 A current. The wiring is heavy and was difficult to run. I think a windlass with a 110 V DC motor would make a lot of sense. Again, the inverter needed would be off most of the time and efficiency is not important. ]

 

I use 110v a/c for charging batteries, electric tools, a vacuum, a portable sump pump and occasionally a work light. Refer is engine drive... it's well insulated... a block of ice works too. My inverter is only 1000w and handles my needs. No blender, toaster or microwave oven. Windlass is 12v, and engine is running when it is used. Don't see the reason for a whole boat 110v system. Simply a bad idea with little to no upside.

 

Thank you all for your feedback!