Assuming you pay $0.12/KWh, can you ever come out ahead going full offgrid?

[Alkaline]

I see a lot of people now doing full house solar/battery and it looks appealing, esp the part going full off grid... But the numbers.... tricky.

My electric is about $0.12/KW and I'm in Orange, Tx, the utility averages about $168/Month on a 1200' house but but I can put up about 15 KW of solar panels.

I figure total cost with my setup would be about 64KW of batts and 13 KW of inverter power (dual inverters sungold power clone LV6548), and 15KW solar panels would be about $45,00.00 assuming I do most of the work.

That would be 22 or so years of electric bills (with inflation, I guess we could say 19 years), and that is assuming nothing breaks on the batts/inverters/solar panels We all know electric companies are basically paying nothing to buy back power so everyone is trying to use batteries but this seems like a very risky deal.

How are you factoring in the cost, or if you have reliable utility power, don't even bother with solar at all?

 

[MurphyGuy]

You can almost always come out ahead with grid-tied solar.

You can almost never do the same going off grid.. because of the cost of the batteries.

If you have access to grid power, going off grid is financial foolishness. You will not beat the cheap cost of grid power.

Off grid setups have two purposes: 1) When the grid is just not available 2) For those who wish to have some backup power for when the grid fails.

 

[timselectric]

I have very reliable utility. (For now)
I'm planning for retirement with no utility bill.
You just have to shop around for really good deals.
I'm installing 40kw inverting power, 60kw solar, and at least 200kwh of battery storage. And I am doing it for under $20k USD.
ROI calculated at 10 years. But probably less with the way utility prices are going.

 

[sunshine_eggo]

Full DIY off-grid can get you close to break-even. With quality tier-1 equipment, you're looking at about 20-25 years for full off-grid payback. Cheap stuff can shave several years off that. Even so, at that point, you may be looking to replace your PV, so the clock starts ticking again.

 

[Alkaline]

Yeah that's what I was thinking, if you have reliable grid then this isn't going to work. I have entergy, only time we have an issue is if there is a hurricane, but I imagine solar panels would get damaged during the hurricane as well.

 

[MaineJim1821]

Here in Maine the cost of electricity is skyrocketing,not geting into as to why.
Right now the kw costs just over 32 cents and will be going up another 20-30% at the end of the year to add to the 49% this january and to the 84% increase of last year.
So solar is not a bad idea but the amount of sun we get is pretty short over the winter,it would take a lot of panels to overcome that.
My usage is very low and i supplement it with solar.Also comes very handy when the power goes out which is fairly frequent where i live.

 

[timselectric]

Grid-tied used to be a great option.
Now it's a suckers bet. Between the utility companies and the governments, you will eventually get screwed.

 

[740GLE]

Here in Maine the cost of electricity is skyrocketing,not geting into as to why.
Right now the kw costs just over 32 cents and will be going up another 20-30% at the end of the year to add to the 49% this january and to the 84% increase of last year.
So solar is not a bad idea but the amount of sun we get is pretty short over the winter,it would take a lot of panels to overcome that.
My usage is very low and i supplement it with solar.Also comes very handy when the power goes out which is fairly frequent where i live.

New Englands higher rates might have something to do with maine voters being bamboozeled by big oil and shutting down the corridor.

 

[Alkaline]

Grid-tied used to be a great option.
Now it's a suckers bet. Between the utility companies and the governments, you will eventually get screwed.

Exactly, they can decide you will not get back anything for the power you generate which Is why I was looking at offgrid inverters from voltronix, I just 1 of the sun gold power ones looks good.

I'm also not sure I will get the federal tax credit if I do this my self as I'm sure they are going to want a certified installer.

 

[timselectric]

Diy is fine. You just can't claim you labor.

 

[Ampster]

Great question, but could @Alkaline change the title to read kWh instead of kW.

 

[nc73]

Negatory. If I could start over I'd abandon solar. It just consumes a lot of my time, but that's probably my fault. Grid is maintenance and worry-free.

 

[EastTexCowboy]

Exactly, they can decide you will not get back anything for the power you generate which Is why I was looking at offgrid inverters from voltronix, I just 1 of the sun gold power ones looks good.

I'm also not sure I will get the federal tax credit if I do this my self as I'm sure they are going to want a certified installer.

I'm right up the road from you out by Lake Livingston. We're on SHECO and are paying around $0.13 per kWh. So far I have 14kw of panels, 30kWh batteries, and two of the MPP Solar LV6548 AIO inverters. I'm about $30k all in, including wiring, fuses, bus bars, gizmos, gadgets, tools, and some labor I paid a couple guys to help me install panels. I'll never get my money back unless utility rates triple but that's not why I went this route. As @timselectric put it, I don't want to deal with the power company for sure and the government at some point most likely. That means off-grid was my only option. I'll get some of my money back and in the meanwhile I'm a little more self-sufficient, which was the primary goal all along. I'll probably add more down the road. We're not right on the coast like you, although I lived down there for 20 years, but we can still get hammered with hurricane damage. You may remember when Rita came through and Jasper (and even farther north) was without power for a month. Of course that's assuming my solar survives the hurricane but that's the plan. If that stuff is important to you then it's just a matter of whether you're willing to invest the money for the peace of mind knowing the payback is minimal. Okay, I have to admit it's been a fun project as well, but that's bonus.

 

[PreppenWolf]

Don't put solar in to save money. And definitely don't put solar in DIY to save money. You can likely spend the time it will take you to DIY working and earning more money to cover grid than you would ever hope to save with solar.

Put solar in because you don't want to be reliant on the grid.

 

[Mike 134]

I have very reliable utility. (For now)
I'm planning for retirement with no utility bill.
You just have to shop around for really good deals.
I'm installing 40kw inverting power, 60kw solar, and at least 200kwh of battery storage. And I am doing it for under $20k USD.
ROI calculated at 10 years. But probably less with the way utility prices are going.

I would love to see your quotes for that lowball price. I installed a 7.2KW grid tied system myself no batteries and it cost $8500 USD. Granted it was new equipment from a supply house with contractor pricing and not used Ebay stuff.

 

[Rednecktek]

Off grid setups have two purposes: 1) When the grid is just not available 2) For those who wish to have some backup power for when the grid fails.

This for me. Solar breaks even pretty quick when compared to gasoline for the generator. Also there are places in the country (and around the world) where the power bill isn't too bad because it's down so often.

Grid tied to me just never made sense, especially here in the Pacific Northwest, because the ROI on a grid tied array, even with the tax breaks, is longer than the lifespan of the panels. It's only getting worse as more and more utilities cut back on what they pay back.

 

[Hedges]

I think you can buy hardware for GT PV at a cost of $1/W, produce power for $0.025/kWh amortized over 20 years, if DIY labor is free.

I think you can buy LiFePO4 batteries (server rack or DIY) in the $0.10 to $0.30/Wh capacity range, may amortize down to $0.05/kWh of cycle life if they do in fact last as long as claimed (don't be surprised if some repair is needed.) Battery inverter I haven't attempted to price.

Compared to $0.12/kWh that doesn't leave much savings.

My approach is grid-backup, undersize battery oversize PV, most loads run PV direct while grid is down and excess production is curtailed.

 

[robby]

Full DIY off-grid can get you close to break-even. With quality tier-1 equipment, you're looking at about 20-25 years for full off-grid payback. Cheap stuff can shave several years off that. Even so, at that point, you may be looking to replace your PV, so the clock starts ticking again.

That is very dependent on what your paying for power but if your talking about 12 cents/KWh then Yes!
Also how much power you use is another factor. The difference in price between a 8KW inverter and 15K inverter is only 33% more in costs for just about double the power. Panels can be bought cheap and batteries can be cheaper brands. The lack of Tier1 batteries to match a Tier1 Inverter will cause some extra level of work but it might not be an issue for some people.

The main thing is your utility rate. If it is 35 cents then that Tier 1 equipment will pay for itself while your still under the 10 year warranty. Also I have no doubts that power prices are going to be moving up significantly as each year passes.
Even now my neighbors are asking around if it's just them or has anybody else's power bill gone up by a lot. I just smile.

 

[timselectric]

I would love to see your quotes for that lowball price. I installed a 7.2KW grid tied system myself no batteries and it cost $8500 USD. Granted it was new equipment from a supply house with contractor pricing and not used Ebay stuff.

I haven't paid full price for anything except for the first AIO and one server rack battery. Everything else was either on sale (cells), used (solar panels) , purchased from the marketplace in this forum (equipment people bought and changed their mind about), or leftover parts from jobs (boxes, panels, conduit, wire, ect).

 

[Ampster]

If I could start over I'd abandon solar. It just consumes a lot of my time, but that's probably my fault.

Fault? I am in the same boat, it has become a compelling hobby. I built a Heathkit 65 years ago and little did I know that beating my utility out of dollars would be my passion when I retired. In California with summer peak rates as high as $0.55 it has become a financially rewarding hobby.