Need design advice for my first build

[tonhtubra]

I'm working on my first build and I have a few questions for more experienced people and am looking for some guidance. Here is some background of what I am dealing with:

• This is for a semi-permanent 27' long 1979 Swiss Colony trailer that has sat up in the mountains of Colorado for over 25 years. A roof and deck have been put up over and next to the trailer, so it sort of has a cabin feel to it, but in theory the trailer could still be pulled out someday.
• There are 110v outlets and appliances like an AC unit, but according to my dad none of it worked when they got the trailer and he doesn't think it is possible to reconnect that system at this point.
• My dad previously had a couple of small solar panels (5w and 15w I believe) that he used to charge 3 AGM batteries that were used to power some interior lights, a water pump, and well that's about it. They used all very sparingly as they would run out of charge if they left any on for too long.
• Those solar panels were blown off the roof last year and broke so there is currently no electrical power at all.
• My gf and I will only be visiting the trailer maybe one weekend a month and probably only staying for at most 4 or 5 days in a row but most of the time it will be arrive friday evening leave sunday afternoon type of trips.
• I would like to build a system that can power the internal lights (which I plan on replacing with LED lights) and the water pump, and can also be used to provide some power for recharging phones, lanterns, tool batteries, other electronics, etc. when we are up there. Maybe in a few years we could even have it power a microwave and run the refrigerator off of electric instead of propane.
• I do think it would be really cool if what I build can keep a basic video monitoring system up and running when we aren't there so we can see often wildlife like moose or bears wander by. This would be especially cool if it could work over winter as the trailer is inaccessible from about September to May.
• I plan on replacing just about all of the original components and I'm using Will's "Classic 400-watt Solar Package" as a guide, although for cost I may only start with 200-watts of panels with the plan of adding two more down the line.
• I'm hoping to keep the total cost of the system under $1400 in this first iteration.

Here are some of my questions:

• Questions about SOK batteries:
  • Due to the cold that can occur in early fall and late spring when nearly at 10,000 feet in Colorado, how helpful would the heated battery option be?
  • How helpful do you think an SOK where I could change out individual cells would be over a cheaper battery without this ability?
  • If I get one with Bluetooth, does this negate the need for a battery monitor or bluetooth shunt?
• Battery Size vs Solar panel array size
  • There are some tall lodgepole pines that limit the amount of sunlight received each day. My hope is to someday have maybe two sets of 4x100w panel arrays on the roof, and at least 200Ah of battery storage, but for now, I'm thinking I need to stick to one of the following two options:
    • A 200Ah lower quality LiFPbattery and only two 100w panels
  • A 100Ah SOK battery and possibly four 100w panels, although might start with just two
• Since this is a semi-permanent structure, should I be looking at making this a 24v or 48v system instead of 12v, or the fact that I am primarily looking to power 12v appliances and an inverter make 12v the best option?
• Should I replace the existing fuse block or not? It's old, but nothing is labeled and part of me wants to just leave everything connected to it as is and just plug in the power
• Given the presence of the trees and the lack of consistent sunshine across the roof, recommendations on how to connect the solar panel array?

I've attached a few images showing the existing setup in the battery compartment in the back of the trailer and the rooftop where the solar panels will go for reference.

I appreciate the help and let me know if you need any additional information.
Thanks!

 

[sunshine_eggo]

Here are some of my questions:

• Questions about SOK batteries:
  • Due to the cold that can occur in early fall and late spring when nearly at 10,000 feet in Colorado, how helpful would the heated battery option be?
  • How helpful do you think an SOK where I could change out individual cells would be over a cheaper battery without this ability?
  • If I get one with Bluetooth, does this negate the need for a battery monitor or bluetooth shunt?

LFP batteries are best when you cycle them regularly. If you're going to be gone most of the time, they may not make the most sense. Quality AGM will perform well in most climates.

• Battery Size vs Solar panel array size
  • There are some tall lodgepole pines that limit the amount of sunlight received each day. My hope is to someday have maybe two sets of 4x100w panel arrays on the roof, and at least 200Ah of battery storage, but for now, I'm thinking I need to stick to one of the following two options:
    • A 200Ah lower quality LiFPbattery and only two 100w panels
  • A 100Ah SOK battery and possibly four 100w panels, although might start with just two

Panels determine how much energy you can use daily.
Batteries determine how long you can go between charges.

• Since this is a semi-permanent structure, should I be looking at making this a 24v or 48v system instead of 12v, or the fact that I am primarily looking to power 12v appliances and an inverter make 12v the best option?

system voltage depends on system size. If you never expect to power anything over 2000W, 12V is fine.

• Should I replace the existing fuse block or not? It's old, but nothing is labeled and part of me wants to just leave everything connected to it as is and just plug in the power

Normally, I would say since there's already something there, it seems sensible to leave it in place, and label it once you have power to it and can determine what's what... however, I see a lot of corrosion. Replace.

• Given the presence of the trees and the lack of consistent sunshine across the roof, recommendations on how to connect the solar panel array?

Trees will kill solar production.

Is there any more favorable place you could mount the panels on the ground?

I've attached a few images showing the existing setup in the battery compartment in the back of the trailer and the rooftop where the solar panels will go for reference.

Those are not AGM batteries. Those are flooded lead acid and require regular maintenance and adding distilled water to maintain them.

 

[Rednecktek]

Do a search for "Blurb time" under my username, that'll get you pointed in the right direction.

Here's a few thoughts though,

This is REAL similar to my cabin out in Eastern WA and I've spent a few years un-fsking the electrical system. I had very little funds to get everything working so I went with 4 of the WallyWorld 29dc batteries because they were good for about 60ah each for $100 out the door.

Tracing out my 12v system and replacing the fuse block was a good project and worth the day to know what went where and get a solid fuse block in there.

Shading was also a major issue so I had to make a ground mount in the sun. The nice thing about that setup is I can leave the SCC and 400w of old house panels on all the time and not worry about the temperatures.

Spend some time tracing out your 120v system, if it is actually messed up it's probably a pretty easy fix. Being able to plug in a generator of any kind (solar, gas, hamster, etc.) really adds a LOT of life quality.

Swapping out existing parts with new versions is pretty easy.

It's a good project! Take your time and tackle 1 thing at a time whether it being the 12v bus or the 120v or the heaters or the windows or whatever. I learned that one the hard way and spent a few uncomfortable days because I started too many projects at once and didn't get my heaters running before it got cold, or had no 120v lights because I ran out of light before I got the 120v all the way back together.

Every time you get a section of the To-Do list done you're going to look back and say "I made that better!" That makes the whole day right there.

 

[Rednecktek]

Blurb time!

Well, I'll start the default answer to these questions and we can work from there. Here's you To-Do list:

1: Power audit! This will give you some important information on how big your inverter needs to be as well as how much battery capacity you'll need. There is a link in the FAQ section (I think, or someone here will post it shortly) so fill in the blanks and see what it comes up with. You'll probably need some sort of Kill-A-Watt to get accurate measurements. Are you going to be running a 12v system? 24v system? 48v system? What are the specs on your solar panels? VoC? Vmp? Being as this is a new build, throw together a wish list of what you want and estimate on the high side.

1a: Where do you live? Speccing out a system for Scotland is a LOT different numbers than Arizona due to the amount of light you actually get. Someone here can post the link to the PVwatts.com or JCR Solar Uber-Sun-Hours calculator sites to help figure out how much you'll have to work with. That will be a box in the Power Audit form.

2: Parts list: You don't need a make & model list, just a parts list to start from for reference. You'll need an inverter, a MPPT charge controller, fuses, shunt, buck converter, batteries, wire, etc. Once you have a basic list it can be fine tuned to make & models after that. If you're looking at the All-In-Ones check for correct voltage outputs (120v or 240v Split Phase for North America, 220v Single Phase for European type areas) and make sure it has enough capacity for a little bit of growth and fudge factor.

3: Budget!: Steak is great but doesn't mean anything if your wallet says hamburger. Figure out what you're able to spend now vs what you'll have to cheap out on now and upgrade later.

4: Tape measure! Figure out where you're going to stick all the stuff you'll need. A dozen 3000AH batteries sounds great until you're sleeping on the floor because there's no room left for a bed. Is there a compartment that can house all this stuff? Will the server rack batteries fit? Are you going to have to make space? Physics can be pretty unforgiving.

5: Pencil out what you think you need and throw it at us so we can tell you what you've missed (because we ALL miss stuff the first go-round ) and help figure out which parts and pieces you're going to want to get.

Well that's the thing about solar systems, there is no 1-Size-Fits-All answer. Your system will need to be designed to fit YOUR needs. When you design and built the system, it's not going to be the perfect system for me, or Will or 12vInstall or anyone else, but it Will be the right system for You and that's the goal.

As for where to get started, let me throw my standard blurb in here to help point you in the right direction. There's going to be a lot of math and research involved, but that's going to be a LOT cheaper than just buying parts off of someone's list and finding out that it doesn't do what you need.

Don't panic on the Power Audit, you'll actually be doing that a few times. When you do the first pass put in ALL the Things that you might want. AirCon? Sure. Jacuzzi? Why not. MargaritaMaster-9000? Go for it.

The second pass will be the "I Absolutely Need This To Survive" list that isn't going to have much on there.

The third pass will be the "This is what is realistic" audit that you'll use to design the rest of the system.

The Power Audit is going to tell you 3 primary things: 1: How big does your inverter need to be to power your loads? 2: How much battery bank do you need to last $N number of days with krappy weather? and 3: How much solar panel will I need to install to refill those batteries in a 4 hour day (the average usable sun hours rule-of-thumb).

Once you know what you Want and what you Need and what your budget can Afford there will be somewhere in that Venn diagram where those three things meet.

After that, THEN you can start looking at parts.

Yes, it's a long drawn out process, but it's worth it in the end. Not every house has the exact same floorplan, not every vehicle is the same make & model, and not every solar system is designed the same.

 

[tonhtubra]

Sorry, I accidentally hit post before I meant to, disregard this post

 

[tonhtubra]

LFP batteries are best when you cycle them regularly. If you're going to be gone most of the time, they may not make the most sense. Quality AGM will perform well in most climates.

Good to know. My thought was to use LFP because the life on it should Last a long time and I would get a full 100aH from one battery and not have to buy multiple AGMs

I'm still curious about the bluetooth that comes with the battery and whether that means I can skip a battery monitor and/or BT shunt?

Panels determine how much energy you can use daily.
Batteries determine how long you can go between charges.

Yeah, I guess I was hoping for more feedback about whether it would be better to figure out my batteries now or my panels because it might be easier to add additional components of one type later than the other. Whether it be for cost reasons (better to buy one or the other now because prices keep going up greater for one over the other) or compatibility reasons (best to get groups of panels together to ensure similarity, etc).

Trees will kill solar production.

Is there any more favorable place you could mount the panels on the ground?

Unfortunately, no there isn't. Anything on the ground would have to be approved, and they aren't going to approve something like that and the only spot on the ground that gets good sunlight anyway is the parking space next to the trailer.

Those are not AGM batteries. Those are flooded lead acid and require regular maintenance and adding distilled water to maintain them.

You're right, I just have begun to think of them as such because nobody recommends flooded lead acid ever and just began to assume they were even though knowing I'd have to add water to them if I had any hope of using them in the future.

 

[tonhtubra]

This is REAL similar to my cabin out in Eastern WA and I've spent a few years un-fsking the electrical system. I had very little funds to get everything working so I went with 4 of the WallyWorld 29dc batteries because they were good for about 60ah each for $100 out the door.

Yeah, I generally like to go with an approach of not skimping because generally if you buy a step up above the cheapest, you get a part that is more economical over time, but another part of me just wants to get something up and running and then improve it once I see where the weaknesses are.

Tracing out my 12v system and replacing the fuse block was a good project and worth the day to know what went where and get a solid fuse block in there.

Yeah, I am definitely intimidated by the thought of trying to deal with the mess of the existing fuse block, but I will be happy that I do once it is done.

Shading was also a major issue so I had to make a ground mount in the sun. The nice thing about that setup is I can leave the SCC and 400w of old house panels on all the time and not worry about the temperatures.

Unfortunately, I can't make a ground mount. Community guidelines won't allow it and the only spot near me that gets good light is the parking spot.

Spend some time tracing out your 120v system, if it is actually messed up it's probably a pretty easy fix. Being able to plug in a generator of any kind (solar, gas, hamster, etc.) really adds a LOT of life quality.

Yeah, I think at some point I will see if I can get it back up and running because it would be really nice to be able to use the plugs inside rather than just running an extension from the inverter to the patio to recharge things.

It's a good project! Take your time and tackle 1 thing at a time whether it being the 12v bus or the 120v or the heaters or the windows or whatever. I learned that one the hard way and spent a few uncomfortable days because I started too many projects at once and didn't get my heaters running before it got cold, or had no 120v lights because I ran out of light before I got the 120v all the way back together.

Every time you get a section of the To-Do list done you're going to look back and say "I made that better!" That makes the whole day right there.

Yeah, the To-Do list for this place is quite large. The big projects that I need to get taken care of before we will feel comfortable staying for more than a night are getting electric back up and working, and getting propane service setup again. One means we can have some lights, running water, and conveniences. The other means we can use the oven/stove, have a refrigerator, and run some propane lights that also provide a bit of heat. The propane has been really tricky though because nobody wants to give me a 120-150 pound tank since there is a shortage and I'd only need it refilled once a year. So for now I'm focusing on the electric.

As for your second post. I haven't done the Power Audit yet, but I did make my own spreadsheet after reading Will's book. I have estimated that I will need 502 watt hours after I replace all the 12v lighting with LEDs, but looking into the future, if I switch the fridge to 12v instead of propane and add a microwave, then my daily watt hours jumps to 1192, but those updates are probably several years off.

Thanks for the encouragement!

 

[HarryN]

The audit is fine, but as a practical matter, mostly it will just help you to ration vs change reality.

Solar panels are cheap compared to batteries so if possible, start with more solar than you think and then add battery capacity over time.

There really isn't any point in putting up less than 400 watts of solar, so the only question is if that is enough or if you should just double it.

Strip out everything that is in there now that is electrical and just start with a 24 volt system and buy 24 volt compatible accessories.

_____________
As others above have mentioned, good quality AGMs are the right path for your application. A pair of Lifelines, Odyssey or Northern batteries in the 100 - 125 amp-hr range marine type battery wired in series will go a long way toward your goals.

_____________
I would skip using old water plumbing components for sanitary reasons. For now, bring some bottled water. About 10 years ago, my 12 yr old daughter really suffered from a water born illness and we are pretty careful. Don't try to save money on water related aspects. Water born creatures are remarkably resilient.

When you are ready to have a real plumbing system, just buy a 24 volt pump and all new water related items.

__________

24 volt LED strip lights are very common and reasonably priced.

_____________

Dual 12 / 24 volt USB ports are common. Same with refrigerators when you reach that point.

________

A decent quality inverter costs as much as your budget, so perhaps wait on that item and rely on DC for now.

 

[Rednecktek]

Unfortunately, I can't make a ground mount. Community guidelines won't allow it and the only spot near me that gets good light is the parking spot.

Bummer. Can you trim a few branches to open up some sun to that roof? You're going to want to seriously consider split panels and going with a combiner box so you can get everything in parallel to deal with the shading.

Yeah, I generally like to go with an approach of not skimping because generally if you buy a step up above the cheapest, you get a part that is more economical over time, but another part of me just wants to get something up and running and then improve it once I see where the weaknesses are.

I'm a huge fan of Tier-2 equipment. It's a much better value IMHO. Get the idea of "Doing something then figuring out later" right out of your head. Failing to plan now is going to cost you a LOT of money, time, and effort and you're going to be frustrated. Trust me on this, I've paid a LOT in "Tuition" trying to figure all this stuff out years before this forum came along.

Yeah, I am definitely intimidated by the thought of trying to deal with the mess of the existing fuse block, but I will be happy that I do once it is done.

A second person REALLY makes this job easier, they can yell down the hall and tell you what's blinking.

Yeah, the To-Do list for this place is quite large. The big projects that I need to get taken care of before we will feel comfortable staying for more than a night are getting electric back up and working, and getting propane service setup again. One means we can have some lights, running water, and conveniences. The other means we can use the oven/stove, have a refrigerator, and run some propane lights that also provide a bit of heat. The propane has been really tricky though because nobody wants to give me a 120-150 pound tank since there is a shortage and I'd only need it refilled once a year. So for now I'm focusing on the electric.

No reason you can't grab a couple of 40lb tanks from the local tractor supply for now and just swap out the tank later. The piping isn't going to change.

As for your second post. I haven't done the Power Audit yet, but I did make my own spreadsheet after reading Will's book. I have estimated that I will need 502 watt hours after I replace all the 12v lighting with LEDs, but looking into the future, if I switch the fridge to 12v instead of propane and add a microwave, then my daily watt hours jumps to 1192, but those updates are probably several years off.

Grab the form from the Resources section and you're going to fill it out at least 3 times. The first time you start filling in the blanks go wild. Hot plate? Sure. AirCon? Go for it. MargaritaMaster-9000? Absolutely! The second time you go through it do the bare minimum you'd need to survive without killing yourself because you couldn't see or whatever. The third time around, now that you've got an idea of how the form works try to go for the realistic "This would be comfortable but not excessive" build out. The form will do the math on how much battery and inverter and panels and such for you. Once you know what you need to provide, THEN start planning out the equipment. When you start narrowing down a parts list, consider upsizing things when you can. Need a 40a SCC? How much extra would it cost to get a 60a instead so you can add panels later. Wire size says 8AWG? Why not go for 4AWG now so you can have that overhead later. If you can spend 20% or so more up front it's a better option than spending 100% now AND 120% later to do the same thing. Make sense?

As a rule of thumb you need 10a of SCC per 100w of panel at 12v.

Even with your 1192wh estimate that's still only a single 100Ah battery in LFP or 200Ah in lead acid flavors which is not much.

Good to know. My thought was to use LFP because the life on it should Last a long time and I would get a full 100aH from one battery and not have to buy multiple AGMs

If you don't have to worry about the batteries freezing then LFP is the way to go. Watt hour per watt hour LFP and AGM are about the same price, FLA is significantly cheaper but can require a little more maintenance. Personally, I really love the WallyWorld DC29 batteries because they're only about $100ea out the door and give you about 660Wh before you start damaging them. Plus, there are WallyWorlds everywhere so grabbing another one is easy. If given the option, a 200Ah 12v battery with low temp protection would be a great starting point!

I'm still curious about the bluetooth that comes with the battery and whether that means I can skip a battery monitor and/or BT shunt?

It's handy for keeping an eye on how out of balance your batteries are, but really a decent shunt is a really handy easy reference that anyone can use and will be more accurate.

Yeah, I guess I was hoping for more feedback about whether it would be better to figure out my batteries now or my panels because it might be easier to add additional components of one type later than the other. Whether it be for cost reasons (better to buy one or the other now because prices keep going up greater for one over the other) or compatibility reasons (best to get groups of panels together to ensure similarity, etc).

The Power Audit form will calculate out what size array you'll need to recharge the batteries you need for $n number of days. In your case, because of the shade and lack of space to work with you'll want to spend real money on split panels and overpanel a lot.


I would also recommend sticking with a 12v based system for a couple reasons. 1: 12v stuff is already a very well supported voltage for DC stuff including lights, USB sockets, diesel heaters, etc. 2: You can buy a 12v lights and adapters and fuses and such at any auto parts store, 24v is going to be online order or $$RV/Maritime Specialty$$$ only.

 

[50ShadesOfDirt]

I would go "clean slate", after seeing the pics. Better to chuck out the old stuff, as the new stuff is just flat out easier to integrate.

I would go 24v as your core system voltage, unless you have the money to go 48v right from the start. I would go with LFP, and plan on more of an "automated" system, where the battery bank will be cycled at least 4 times per month, but perhaps more like 8 with some automation. It is just too easy these days to build a battery-bank box that is insulated to begin with, and holds/warms critical components. This would also allow the house to keep power while you are gone, and depending on your "internet" capability, might allow you to monitor it remotely. Or, you could choose to run off of battery-bank during the week, when gone, and recharge it the moment you get there on the weekend. Plenty of "patterns" to choose from ...

Do you have a fuel generator?

Would your HOA or whomever allow a "carport" or similar parking space cover? If so, it would be easy to build that out of solar panels.

I'd put in the battery-bank, AIO inverter, and connecting wiring to tie it into the house. Now your cabin has power. If a fuel generator is allowed, such as a small/quiet inverter-gen or similar, these can also be put in a noise box (so you can't hear them), automated to come on when battery-bank gets low, and can recharge the battery-bank (from propane, which is a great site fuel) until such time as you get solar panels going.

I use websites like the following to get past some of the initial calculations:

1. Go here, and enter in each appliance's values (watts, hours/day you want to run it, etc.):
https://unboundsolar.com/solar-information/offgrid-calculator
2. Go here, using numbers from above, and fiddle with various entries/components, and you'll see in real-time what your system component (inverter, mppt, panel) sizing is:
https://www.altestore.com/store/calculators/off_grid_calculator/

There are many similar website pages/calculators, but these two pages should help you get through most of the necessary calculations. This helps you quickly decide if you can do what you want to do, and you can vary component choices for what-if scenarios.

Hope this helps ...

 

[50ShadesOfDirt]

Also an option, as you only visit on the weekends, is to build a DIY solar generator, which you can work on at home base, and then bring up to the cabin. Once you know the interconnections into the cabin, it would be fairly easy to tie the solar generator into it, and be up and running.

Don't let the hand-truck scheme of these things fool you ... the components would be 24v or 48v and mobile to start, but would also just mount right into your newly designed (whatever) to be a permanent part of the cabin.

 

[tonhtubra]

Bummer. Can you trim a few branches to open up some sun to that roof? You're going to want to seriously consider split panels and going with a combiner box so you can get everything in parallel to deal with the shading.

This is the first time I have heard of a combiner box. Is this just to help me with making sure I'm optimizing the panels even if I am adding a variety of sizes and types to get as much coverage on the roof as I can?

No reason you can't grab a couple of 40lb tanks from the local tractor supply for now and just swap out the tank later. The piping isn't going to change.

Yeah I might have to go with this. I just don't know how much my parents modified things and the only working line might be from the old 120 gallon tank that used to be up there. Plus, that is a lot of space taken up by propane tanks each time we go visit.

If you don't have to worry about the batteries freezing then LFP is the way to go...If given the option, a 200Ah 12v battery with low temp protection would be a great starting point!

Yeah, that is the thing I guess. It will get really cold up there in the winter, and if I'm hoping to have this thing running a couple of cameras and a small computer to store the data over the winter. I'm not even sure insulating the battery compartment would be enough when we are talking about being at 10,000' elevation. I also have no idea how deep the snow gets and if the solar panels will be covered by snow for a lot of the winter.

It's handy for keeping an eye on how out of balance your batteries are, but really a decent shunt is a really handy easy reference that anyone can use and will be more accurate.

Ok that is what I was thinking. Now just to decide whether to go with the one you link, which I would have to extend the wiring on it and figure out how to mount it somewhere without doing too much damage, or to spend nearly twice as much for the Victron bluetooth shunt.

The Power Audit form will calculate out what size array you'll need to recharge the batteries you need for $n number of days. In your case, because of the shade and lack of space to work with you'll want to spend real money on split panels and overpanel a lot.

Man, I wish I had known about the Power Audit form before I spent the time to make my own spreadsheets. It is nice to see that my own spreadsheet was going down the right path, but this one is so much easier to use and I trust the calculations even more. I wasn't accounting for the efficiency loss of the Inverter before so the Power Audit now has me at 1338 Battery W-hrs and 111 Battery A-hrs as minimums. That has me thinking that maybe I invest in the 200Ah battery now in the hopes that while we are gone there will be plenty of time for the solar panels to charge the battery and then we should be able to make it through a weekend without losing power, but if we do, then I start adding panels.

I would also recommend sticking with a 12v based system for a couple reasons. 1: 12v stuff is already a very well supported voltage for DC stuff including lights, USB sockets, diesel heaters, etc. 2: You can buy a 12v lights and adapters and fuses and such at any auto parts store, 24v is going to be online order or $$RV/Maritime Specialty$$$ only.

That is the thought I am getting now too. Some of the others recommending 24 and 48 I think are missing that this isn't an actual cabin and that there are 12v appliances already in place and they are the only appliances and features that currently can be operated without plugging directly into an inverter.

 

[tonhtubra]

I would go "clean slate", after seeing the pics. Better to chuck out the old stuff, as the new stuff is just flat out easier to integrate.

Yeah that is my plan other than running new wiring throughout the trailer, but everything in the battery compartment is going to be getting replaced.

I would go 24v as your core system voltage, unless you have the money to go 48v right from the start. I would go with LFP, and plan on more of an "automated" system, where the battery bank will be cycled at least 4 times per month, but perhaps more like 8 with some automation. It is just too easy these days to build a battery-bank box that is insulated to begin with, and holds/warms critical components. This would also allow the house to keep power while you are gone, and depending on your "internet" capability, might allow you to monitor it remotely. Or, you could choose to run off of battery-bank during the week, when gone, and recharge it the moment you get there on the weekend. Plenty of "patterns" to choose from ...

Unfortunately there is no sort of connectivity up there. To even get cell reception up there I have to drive out and head to the nearest town about 30 minutes away. Some people have DirecTV dishes, but I'm not doing that for how little I will be up there and the costs associated.

Do you have a fuel generator?

There is one up there, but there are restrictions on which days you can operate them. I will only use it in the case of an emergency or if I really need the extra juice for a big project.

Would your HOA or whomever allow a "carport" or similar parking space cover? If so, it would be easy to build that out of solar panels.

Very small chance of that. It would probably have to extend from the existing roof and that wouldn't really be all that much better in terms of getting out in the open, and I don't have the money to build that right now.

 

[tonhtubra]

I would skip using old water plumbing components for sanitary reasons. For now, bring some bottled water. About 10 years ago, my 12 yr old daughter really suffered from a water born illness and we are pretty careful. Don't try to save money on water related aspects. Water born creatures are remarkably resilient.

When you are ready to have a real plumbing system, just buy a 24 volt pump and all new water related items.
[\QUOTE]
Yeah, the water going through the water pump has only been used for things like washing dishes, showers, and well that's about it and that is all I would use it for going forward and even that makes me a bit nervous for the reasons you mentioned. We always haul up drinking water when we go up.

A decent quality inverter costs as much as your budget, so perhaps wait on that item and rely on DC for now.

I already bought a GOWISE 1500w Pure Sine wave which should work well for me until I get to the point where I am ready to put in a new refrigerator and microwave (if I ever get to that point even.)

 

[tonhtubra]

Thanks to everyone that has chimed in. I have a new question regarding the fuse block. It looks to me like the existing fuse block only has 5 circuits. Is that what everyone else is seeing?

I had been planning on buying the 12 circuit fuse block that Will recommends on his site, but is there any reason why I should go more than say the 6 circuit version? I'm struggling to think if I would be adding any additional 12V appliances than what already exists.

 

[Rednecktek]

Thanks to everyone that has chimed in. I have a new question regarding the fuse block. It looks to me like the existing fuse block only has 5 circuits. Is that what everyone else is seeing?

I had been planning on buying the 12 circuit fuse block that Will recommends on his site, but is there any reason why I should go more than say the 6 circuit version? I'm struggling to think if I would be adding any additional 12V appliances than what already exists.

That 7th circuit? I've always been a fan of having and not needing and it's not like it's that much more expensive than the 6 slot.

This is the first time I have heard of a combiner box. Is this just to help me with making sure I'm optimizing the panels even if I am adding a variety of sizes and types to get as much coverage on the roof as I can?

No, a combiner box is used when you've got something like a 4p array (2s4p, 3s6p, etc.) and rather than using multiple branching Y connectors and inline fuses to get them all together, you have a box that has the inputs, fuses, and usually surge protection all mounted in 1 place for ease of wiring and service. If you have to troubleshoot a string you can just pull individual fuses and take strings offline. Need to reset your SCC or take it offline and don't want power coming into it? Kill off the main breaker inside. Etc.

Yeah I might have to go with this. I just don't know how much my parents modified things and the only working line might be from the old 120 gallon tank that used to be up there. Plus, that is a lot of space taken up by propane tanks each time we go visit.

Adapting from the old line to a portable tank is just a matter of either an adapter or swapping the regulator on the end. A 40lb tank isn't exactly huge and is usually plenty if you're only up there a few days. It's an option to hold you over until you can get a proper serviced tank installed.

Yeah, that is the thing I guess. It will get really cold up there in the winter, and if I'm hoping to have this thing running a couple of cameras and a small computer to store the data over the winter. I'm not even sure insulating the battery compartment would be enough when we are talking about being at 10,000' elevation. I also have no idea how deep the snow gets and if the solar panels will be covered by snow for a lot of the winter.

Definitely low temp protection at the minimum. Much like my camp that doesn't get above freezing for months at a time, this is one of those rare circumstances where FLA or AGM batteries really shine. That 50% capacity hit really hurts though.

Ok that is what I was thinking. Now just to decide whether to go with the one you link, which I would have to extend the wiring on it and figure out how to mount it somewhere without doing too much damage, or to spend nearly twice as much for the Victron bluetooth shunt.

They sell extension cables for those shunts if you need to go that much farther than the provided cable, or a BT shunt will work as well.

Man, I wish I had known about the Power Audit form before I spent the time to make my own spreadsheets. It is nice to see that my own spreadsheet was going down the right path, but this one is so much easier to use and I trust the calculations even more. I wasn't accounting for the efficiency loss of the Inverter before so the Power Audit now has me at 1338 Battery W-hrs and 111 Battery A-hrs as minimums. That has me thinking that maybe I invest in the 200Ah battery now in the hopes that while we are gone there will be plenty of time for the solar panels to charge the battery and then we should be able to make it through a weekend without losing power, but if we do, then I start adding panels.

I know, right! I wish that had been a thing back when I started playing too. Still wouldn't have accounted for the overcast days I got in a valley in Western Washington, but would have been really handy. Remember that if you're using lead acid batteries you need to double that capacity right out the gate which sucks. A 200Ah LFP battery sounds like it would be a little less than 2 days though, I'd swing for a pair of those to account for snow/clouds/etc so your whole system doesn't choke out and die in the middle of the night right before you're heading home.

 

[tonhtubra]

Any suggestions for how to mount my solar panels to the metal roofing? My roofing is trapezoid construction so I was going to purchase the S-5! RibBracket, but the vendor that would have allowed me to order less than 45 at a time seems to not carry them anymore. Even if I do get these, Do you think I could put the panels directly on to these brackets or would I have to use a traditional bracket to connect to the RibBracket?

The Ribs that I would mount to are 9 inches apart. I've attached an image to see what it looks like.

 

[HarryN]

I would try to avoid buying electronics items from amazon if you can - it is difficult to know what you will really get.

Places like altestore, solar-electric, pkys, fisheries supply that are focused on the marine electrical world are what I would suggest.