12 volt batteries, solar panel and inverter.

Beemer! My micro wave is only a tiny 700 watt. Wife usually warms things up in it at lunch time such as a bowl of soup or such once or twice a day at most.

With just a couple of 12VDC batteries you can only expect to use a small INVERTER around 300-400WATTS. INVERTERS take alot of DC CURRENT to operate.

I have a 600WATT PSW INVERTER setup in my off-road trailer and I can draw around 300WATTS from the Home Entertainment items, a couple of fans/lights/ and recharge my cellphone and computers. I also have a WX ALERT RADIO and a few other low wattage items running.

We draw around 20AMPS continuous from the battery between 6PM and 11PM and of course there is a constant parasitic draw of 1-2AMPS all the time. This drops my 255AH battery bank to its 50% charge state by 8AM the next morning which I have to re-charge back up otherwise it will do damage to the batteries.

If you are wanting to run a 1500WATT microwave it will take way over 120AMPS of DC current from the battery bank to operate it.

As stated above you cannot do a LOOP where you have a BATTERY running an INVERTER which in turn runs a Converter that charges the battery. Our science doesn't support this loop except in Star TREX movies. If you could do this then you would have an endless source of power.

To do what you are thinking about will require a very big battery bank and then a way to recharge the batteries when you are off the power grid.

Also all you can expect from a 7W Solar Panel is to trickle charge a battery. This is only good for topping off a charged up battery. I doubt if this 7W Solar Panel will even keep up with your always on 1-2AMPS parasitic drain with your trailer.

To re-charge a single 12VDC Deep Cycle battery in a quick three hour time period you will need 14.4VDC with the capacity of 17-20AMPS of DC current to get the battery re-charged to its 90% charge state. A typical 120WATT Solar panel (alot bigger than your 7W Solar Panel) will only produce around 5-6AMPS of DC current when in the high sun and will only do this for 5-6 hours in a typical high sun day. It would take several 120WATT SOLAR PANELS (around 6 of them actually) if you wanted to re-charge a single 12VDC deep cycle battery in a three hour time period that has been drained down to its 50% charge state.

Will take some serious planning and resources on what will support what you want to do camping off the power grid... take a look at some of the full time guys that live in the RV's 24/7 and note how many batteries they have on-board.

Just saying...
Roy Ken

Thanks good point, That shouldn't have any bearing on the ignition of the fridge or furnace, as they run directly off of the batteries and propane, I don't have a A/C so no problem there.
We usually hook up to grid power when its available but there are times when we like to boon dock where fishing is good and campers are scarce.

A 7 watt panel is nearly worthless.

Your microwave may use 1,000 watts or more. You do the math on the recharge time.

Other than the teeny tiny panel, your plan sounds okay.

grandpa123 wrote:
... and hook this up through my trailer 110 plug in which it would go through that converter to run the micro wave in the trailer.

Not sure I understand that part, but turn off the converter when using an inverter. Batteries cannot charge themselves.