timselectric
If I can do it, you can do it.
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It's an off grid AIO.
Confusion on meaning of Off Grid vs Grid-tie vs Zero Export
- Thread starter jdufford
- Start date
Yurtdweller
Solar Enthusiast
I did not read the whole thread. I am, and always have been, off-grid. I have little authority to speak on anything else. That being said, and with your desires in mind, this is what I would do in your situation. Build an off-grid, standalone system with batteries. Build it like an rv system, which can accept power from the grid to run loads and charge the batteries when they get low, then run whatever loads you choose off that system. In this manner, you will get the advantage of running loads off solar when it is available, and you will have grid backup when needed, without the possibility of back-feeding the grid, and without requiring permissions. You are simply plugging in a battery charger. I believe this is called a 'power island' or something. You could literally purchase an rv power converter, or you can get a charge controller or all-in-one which is purpose designed. Then all you have to do is decide which loads get connected to your solar system. If I'm ever in a situation where I have the grid available, I would do this. This setup will also function as an emergency backup during grid failure. Recommend loads would be things that have fairly consistent use, like refrigerators, home office, ebike or other ev charging, etc. Rechargeable tools, or other critical loads.
As long as I can produce on cloudy days like today, I should be good. And if the AC300 holds out - I'm skeptical, but getting a 2nd battery combo was just $300 over battery alone, so I bought a spare just in case.
Which was a good idea since the 2nd was DOA!Attachments
CaliSunHarvester
Solar Enthusiast
SolarCity charged 25k to 30k for a system back in 2015, approximately 26 x 350W pv
dougbert
Solar Addict
I spent about $30k in parts over the past 24 years for my DIY system
That includes:
2 generations of solar panels (1st generation re-sold)
3 generations of inverters (loaned 1st one out, 2nd generation on my shelf)
2 generations of charge controllers (1st generation re-sold)
3 generations of battery (FLA 6v cells to 2v cells to 24v Tesla modules, 1st gen died, 2nd gen re-sold)
going from 1 array to 4
24v arrays to 48v
mostly same wires, but upgraded grid AC feeders as the new inverters required greater capacity
refactoring (changing) the AC side of things 3 to 4 times as I learned and found better ways to arrange things
That includes:
2 generations of solar panels (1st generation re-sold)
3 generations of inverters (loaned 1st one out, 2nd generation on my shelf)
2 generations of charge controllers (1st generation re-sold)
3 generations of battery (FLA 6v cells to 2v cells to 24v Tesla modules, 1st gen died, 2nd gen re-sold)
going from 1 array to 4
24v arrays to 48v
mostly same wires, but upgraded grid AC feeders as the new inverters required greater capacity
refactoring (changing) the AC side of things 3 to 4 times as I learned and found better ways to arrange things
Ampster
Renewable Energy Hobbyist
That is similar to my story for the past 14 years and I have probably spent more but that is because I have moved three times and recouped some of that expense when I sold two homes. I have gone through three hybrid inverters and more sets of batteries, which I was able to resell. My latest home and system may be the last hurrah, but I have said that before. Technology is tempting.
wattmatters
Solar Wizard
In Australia, "Hybrid inverter" refers to a PV inverter with the capability of DC coupling to a battery. Normally in a grid-tied context but not exclusively.
If true, it sure is.
It's so hard to understand why it's so expensive over there. In my home state, this is the average solar PV installation cost per watt:
Keep in mind this chart is in Australian dollars, so that February price per watt is ~ US 57c/W.
That's the average price for a professionally installed rooftop solar PV system. No battery, just regular grid-tied PV and inverter. The average size of rooftop PV installations is approaching 10 kW.
So even though grid-tied DIY here is verboten, at least the industry is competitive.
Batteries on the other hand are still far too expensive. Which is why those resources here should first be diverted to consumption reduction / efficiency, be it via heat pumps, better thermal properties of the home etc and load shifting to maximise use of solar PV (PV diverters for water heaters, smart EV charge stations, home automation.
The first large battery a home here should buy is an EV. A home battery is last on the list and is mainly bought for energy security reasons, as it typically will not save money.
Ampster
Renewable Energy Hobbyist
That fits within the broad definition. Maybe that means we almost have a global definition. Subject of course to the rule of, "lost in translation". /s
My kiss definition:
Grid tie: has an output, can send power to the grid
Off grid: has an input, can get power from the grid
Hybrid: biderectional, can send to or get power from the grid.
Grid tie: has an output, can send power to the grid
Off grid: has an input, can get power from the grid
Hybrid: biderectional, can send to or get power from the grid.
Sub mode, batteryless inverters would be a very inexpensive way to get into solar without involving the poco. Why are these not that popular?
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timselectric
If I can do it, you can do it.
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Many simple off grid setups have no provisions for grid inputs.
Plenty are purchased. Just not used in this way.
wpns
Solar Joules are catch and release
What do you call the solar setup with no grid connection (ie. cabin in the woods)?
timselectric
If I can do it, you can do it.
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Off grid
Way off grid. lol
wpns
Solar Joules are catch and release
Farfromgriden
clayswen
New Member
I have purchased my sol ark inverter and my solar panels so far. I purchased forty 330 watt panels(great deal). My plan is to put 30 into commission while being grid tied the first year or till more funds are available. Then I would like to expand my pv array. Then I would like to start purchasing good quality 48 volt batteries from then on till I am pretty much self sustained. Just using the grid for emergency situations if needed. I guess my main question is should I be adding batteries first or expanding my array?
MajicDiver
Solar Enthusiast
My recommendation would be to look at the various battery systems that are out there that are designed to be expandable (most) and fit your needs for price and technical complexity. Purchase and install a single module when still grid tied and start learning how to make use of it.
When choosing a battery product, think about the location you will need to install it, how far it will have to be from inverter, will you need to provide for heating/cooling and how willing you are to be deep into the details of its “settings “ and software configuration. Various battery products involve a wide range of technical expertise and attention to detail to setup and operate properly. Choose a product that fits your ability, time and desire to be deep in details or have something that is pretty hands off. Also, think about who might have to keep the system running if you can’t for some reason.
Ampster
Renewable Energy Hobbyist
It all depends on your consumption patterns and the Net Energy Metering plan and the energy rates from your power company.
That's going to be off grid or hybrid. Which, funny enough I would still prefer a hybrid inverter for pure off grid use
timselectric
If I can do it, you can do it.
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Unless you need AC coupling, why would you pay extra for features that you won't use?
MajicDiver
Solar Enthusiast
And you might get a wider range of suggestions if you started a new thread with your battery question, this one is somewhat unrelated.
wpns
Solar Joules are catch and release
So now we add ‘pure off grid’. Clear as mud!
#WeDemandRigidlyDefinedAreasOfDoubtAndUncertainty!
