You need to identify your power consumption during the peak rate time you want to avoid. This will define the storage capacity of your battery system Also identify the circuits that will be powered by battery. This will determine size of your inverter. (For example: air conditioning, water heater, electric range. But not dishwasher, cloths dryer or cloths washer, etc because will not use during peak times More on reddit.com

Just going through this process atm myself! It sounds like you don't have any large draw items listed, but do weigh how likely or unlikely you are to want to add to that list and consider leaving headroom in your battery bank to cover it, especially for inefficiency losses. Some questions to clear up before moving on to deciding on batteries: Are you running solely 12V, 120V or a mix of both? If strictly 12V, this simplifies your wiring circuit and necessary protective and functionality hardware. If 120V or a mix of 12V/120V, you're stepping into the land of inverters and possibly a DC - DC charger so you can efficiently charge your extra battery(s) as you drive rather than relying solely on plug in 115V land power. Solar is a consideration for constant top up if you have the remote need, space and budget. How budget friendly are you looking for? If, like me, you're trying to maximally stretch your dollar, lead acid/AGM style batteries will be your choice over a lithium/carbon foam/etc build. This will also affect things like cabling size and overall cost as well. Weight is a huge factor here as lithium is around half the mass as well as DoD (Depth of Discharge). There's many free tools out there to estimate your capacity needs. I've mainly played with https://www.batterystuff.com/kb/tools/solar-calculator.html ? to get a good idea of what I'd like to aim for. More on reddit.com

This looks like valid math. However, lead acid batteries are recommended to not be drained below half their capacity, so you may want more battery power. And don't expect a cheap inverter to run continuously at full load for three hours. Get a 1000W unit. More on reddit.com

Take the nominal voltage of the battery and multiply by the amp hour rating. That will give you the batter's energy capacity. Divide that by the power draw of you equipment. The units of that result will be hours. If you have a desired runtime, you can take the power draw you've calculated and multiply that by the number of hours needed for your runtime. Then divide that by the nominal voltage of the battery. That will give you the amp rating for the battery. These processes should give you a reasonable approximation of the run time for your items or size of the battery. You should add some extra capacity (or reduce your run time expectiation) to account aging of the battery, temperature changes, etc. 25% is the first number that popped into my head. 5% is probably too thin of a margin. Lastly, be aware that a 12V nominal battery will be less than 12V at end of discharge and more than 12V at start of discharge, so your LED configuration may require a revisit to make sure it works throughout the batter's discharge curve. More on reddit.com