Full Solar Kit

[yaakbus]

I am going to be using my bus/tiny home for a few things ranging from touring the country to promote the launch of my company, to hunting/fishing/backpacking off grid for weeks at a time. I need to have enough power to be fully off grid for at least a week without plugging in. I will be running AC in the bus but want the option to plug into shore power, additional portable solar panels and a generator if needed.

I think I am looking for a system that is at least 800W+. I will be running a fridge, chest freezer, electric furnace, laptop plus two additional monitors, separate computer, printer, sewing machine, nutribullet blender, kruger coffee maker, microwave, lights, outlets, water pump and at least one ac unit, plus a few other things I am sure I am missing.

So I have a few questions. Is 800-1000W enough or overkill for the power I need? What components do I need including panels, inverter, charge control, fuses, batteries, input plugs and what else? What kit/brand is the most recommended without breaking the budget plus how expandable are they? How many and how big of batteries do I need? I have a 40ft bus so I have a lot of space for both organizing the system and panels for the roof.

Thank you for your help.

[brokedown]

This is a regularly asked question.

I'll save you a LOT of time: get a generator.

Don't want to take the easy way? Then you need to spend time working out your actual power requirements. There are web sites where you can calculate your power needs. You're not gog to be happy with the number at the end once you plug all those big appliances in.

Your end result will be that you run a modest solar array and combine it with a generator for when you decide to run your AC or heater.

[Drop out]

AC on solar is a difficult thing to pull off. There is a YouTube video of one working example. They had a larger solar array and the amount of draw is probably enough to reduce battery life by discharging too deep.

I would like to try it myself but I think a 2,000-3,000 watt solar array would be better. Bigger is always better but it also gets you solar shading to reduce your heat gain. I think 2,000 watts is pretty close to a marginal system, you want enough to run AC, top up your battery for night time cooling and deal with any shading issues that might reduce your power generation.

After you have a nice big solar array, you have to worry about batteries. Lead acid is heavy and doesn't like to be discharged deeply so Lithium is the way to go. Lithium gets a bad rap because products like Hover boards and Samsung phones discharge and charge them rapidly and don't give them sufficient cooling. If you install a big enough lithium battery, the draw you might sustain is only a very small fraction of their technical limit. In that type of usage they are very safe and have a long life.

So what is big enough? I would start at 10 kilowatt hours and want more.

This type of system is not cheap. It might not work in all locations because you might get shading that ruins your solar generation but doesn't cool enough to go without AC.

If I can afford the solar system I want, I will still have a generator but in might be a little Honda instead of a big heavy Onan.

I would like to do extended boondocking too but I wouldn't trust even a 3,000 watt system to work without any sort of backup. 10 kilowatt hours doesn't go very far if you aren't generating power but you are running AC.

[Rusty]

Originally Posted by yaakbus

I will be running a fridge, chest freezer, electric furnace, laptop plus two additional monitors, separate computer, printer, sewing machine, nutribullet blender, kruger coffee maker, microwave, lights, outlets, water pump and at least one ac unit, plus a few other things I am sure I am missing.

according to Keurig this MAX draw is 1500 watts. (1500w/120v=12.5amps) Water tank reheat cycle is only 200-400 watts and idle is ~60 watts, again all information directly from Single Serve Coffee Makers & K-Cup Pods | Keurig®

[jazty]

800w worth of solar panels paired with a 500-600Ah battery bank would be plenty for lights, computer stuff, water pumps and kitchen appliances as long as you're energy conscious (turn off devices when not in use). While blenders and the like suck lots of power, they only run for maybe 10 minutes a day.. Same thing with microwaves.

800 watts isn't even close for regularly running an AC unit or (*gasp*) an electric furnace.

I'd say go propane or diesel for the furnace unless you plan on being plugged in to shore power most of the time.. Really.. An electric furnace running off of a generator is about as wasteful as one could get for heating.

- Fuel burns in an engine @ around 35% thermal efficiency.
- Engine turns the generator to create electricity. More efficiency loss.
- Power is transmitted through wires to the heater. More loss.

You can get much higher efficiency with a fuel fired furnace and you won't need the generator to be running to utilize it. The furnace will turn itself on and off and the fans can be run off of the solar system.