How to use solar savings to go off grid(eventually)

[axmking]

Hi all!

(Basically I want to do basic grid tie now, with minimal equipment cost losses, to save money for full off grid later)

Watched a ton of videos (and made one purchase I’m trying to ‘undo’). Eventually I’d love to fully cut my only utility cord.

Until that far off day, I’d like to take advantage of my ample space with unshaded sunlight. The plan is to get as much savings as possible now with what I’m considering a temporary system on somewhat temporary hardware, to help offset the cost of the off-grid plan. Future plan was to use a solark 12k, diy batt banks, etc; near term I have no idea how to get the 100yds from panels I haven’t bought, to the meter.

sorry if this is a dumb post. I think I’m trying to keep to many timelines, revisions, and considerations in my head. Figured prime time to reach out for help. Thank you

btw I’m in Deschutes county Oregon

 

[JeepDaddy]

Welcome to the forum.

What is your question for us?

 

[chrisski]

This is the place you can go to get those questions answered. Welcome.

If you’re want to build something to make use of the sun and store the energy in a battery bank, that would be good. If you’re doing this to save money and maintain the same level of comfort on grid, saving money is just about impossible. With solar, I plan to spend $.50 per kilowatt hour after battery replacement and build expenses are taken into account. In Arizona, its supposed to average about $.13 per KWH Power from the grid.

I have solar in my RV, and I could I make plenty of power for my needs, as long as I don’t cook with electricity, use electric heat, use the air conditioning, or other high wattage appliances. I go from what the average person uses in kilowatt hours at home around 34 kWh, to 3 kWh - 5kwh per day when using the RV.

One of my pet leaves lately is people thinking I’m saving money in the RV. It’s more like paying for 30 years of electricity up front.

I have to say though, the independence I get from the power produced is priceless.

 

[axmking]

Thanks! Agreed on priceless nature of off grid. That’s my goal. It costs what the market decides after I make it there. Just want to make it there first. Near term goal is to play their game and bank that savings in knowledge/equipment. There will certainly be replacement costs but who knows what we‘ll have as options for storage in our own futures. We can all make the best decisions for ourselves and our locales.
Question, since I totally forgot that part haha sorry and thanks @JeepDaddy. Assuming I can blow about $3000 what’s the best grid tie bang for buck? Totally broad but here’s some details: no time of use, no shade, ground mount with 100yd distance to panel.

 

[Hedges]

There are several brands offering grid-tie inverters with battery backup as an add-on.
The ones which will perform nicely have ability to smoothly adjust generated AC power to match loads when off grid (some just turn on full then off, which cycles batteries unnecessary.
There are also some which are batteries optional, so you can add those later.

One way this is implemented is using something like California's "Rule 21" with "frequency/watts" option. The grid tie inverter responds to grid frequency higher than 60 Hz by ramping down watts from 100% to 0% as frequency ramps up. Many grid-tie inverters now support that (but some only "Rule 21" without "frequency/watts". Several battery inverters support frequency shift control.

I use SMA Sunny Boy. Current models (meeting latest code requirements to be permitted for grid tie) cost between $1400 and $1700 for 3000W to 7700W. If your jurisdiction doesn't require latest functions, or if off-grid, older models can be had for less.

PV panels can be had for $0.25 to $0.33/watt, so the remaining $1500 of your budget could buy 4500W to 6000W of panels. Total $3000 for up to 6000W of PV, but you have to build ground mounts and run wires for free to stay within budget.

I use Sunny Boy battery inverter. Retail is about $5000 but there are some liquidation sales $2000 to $2500. One Sunny Boy plus a 120/240V transformer and a 48V battery completes an off-grid system.

Other brands like Schneider and Outback off similar functions.
Enphase (microinverters) has boxes with micro battery inverters.

Solar Edge, I think, requires replacement of GT inverter with a different GT/Battery inverter.

SolArk is a hybrid that combines functions at lower cost. I think it is batteries optional, so you can add that later. It will cost more than a Sunny Boy but less then Sunny Boy + Sunny Island.

Going off grid, you have to think about what loads you need to run. A well pump may be too much for SolArk to start, depending on motor size. Sunny Island (and some others) you can parallel several (at great expense) and run anything. See if SolArk supports parallel connection.

100 yards - You can do that with fat enough AC wires. I have 200' of wire across my property.
But I prefer to run distances with high voltage PV wires (600V max open circuit, about 380Vmp) because larger voltage drop is just efficiency loss, doesn't keep motors from starting or cause grid voltage to be seen as out of spec.
Bury 2" PVC conduit and you can pull whatever you need.

 

[axmking]

Thank you very much! Exactly what I was looking for. I now need to hunt down all the regs I need to meet to see if I can pickup something a little less new like you said. Seen some used for a bargain. Any tips on gathering those codes?

 

[Hedges]

Thank you very much! Exactly what I was looking for. I now need to hunt down all the regs I need to meet to see if I can pickup something a little less new like you said. Seen some used for a bargain. Any tips on gathering those codes?

Look up what version of NEC has been adopted by your state. See when they plan to adopt which version next. That will define most of the required features. Final say comes from permit office and inspector.
Forum member ArthurEld posted about his experience installing SolArk in Florida, which you can read about. He made sure he had plans approved by the city before he bought anything.