Massachusetts has a great deal (I understand) for installing a battery with solar installations. I question why anybody would even consider adding one when for the cost of a battery plus the electronics you could have a damned good diesel generator installed. Those who enjoy gas for heating and such would have one powered by that. My daughter has one for her home and it turns on automatically whenever a power outage occurs. Just my thoughts—- I will enjoy my solar without a battery
Why batteries???
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timselectric
If I can do it, you can do it.
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To each their own.
Finca Life
New Member
Can't imagine running my generator for 14 hours plus every night in the winter.....
Bluedog225
Texas
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Why have a flashlight when you can build a fire? Modern hocus pocus.
42OhmsPA
What's in a title?
Why not batteries?
Who likes the noise of a generator or trying to refuel in pouring down rain, wind, snow? Don't forget the oil changes. Don't forget the generator exhaust will get ya if not installed correctly. What generator transfers fast enough that electronics aren't affected when grid goes down?
I had to break mine out to charge my batteries a few weeks ago, forgot how much I loved generators ?
Who likes the noise of a generator or trying to refuel in pouring down rain, wind, snow? Don't forget the oil changes. Don't forget the generator exhaust will get ya if not installed correctly. What generator transfers fast enough that electronics aren't affected when grid goes down?
I had to break mine out to charge my batteries a few weeks ago, forgot how much I loved generators ?
Hedges
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Diesel generator cost of ownership is around $1/kWh
PV (parts only) $0.025/kWh, or including installation up to about $0.10/kWh (amortized over 20 years)
Batteries cost as much as $0.50/kWh or as little as $0.05/kWh, depending on chemistry, model, source.
Depending on utility rates, batteries may be a good deal or not.
If there are incentives to install them, need to make sure they aren't a bad deal.
PV (parts only) $0.025/kWh, or including installation up to about $0.10/kWh (amortized over 20 years)
Batteries cost as much as $0.50/kWh or as little as $0.05/kWh, depending on chemistry, model, source.
Depending on utility rates, batteries may be a good deal or not.
If there are incentives to install them, need to make sure they aren't a bad deal.
- Diesel generators need regular upkeep/maintenance
- Generators also require fuel to run (whereas a solar + battery system do not)
- If you have a decent Solar/Inverter/Battery system, you can usually do 120V AC infeed to get power from a generator (big or small).
- You can use a small/quiet inverter generator to top off the battery as needed and run silently otherwise (e.g. fire up generator once every 12+ hours)
- Overall less reliance on fossil fuels (cost, storage, environmental considerations, etc.)
- Automatically turns on? ...Battery/Inverter systems often have an instantaneous "UPS" switchover if power goes out. No interruptions
Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
Hmmm... let's put it another way for you.
I run 1300AH/33kWh of LFP Battery. Solar can charge it on a sunny day but in winter am subjected to days without sun (really north). 1300AH = 10 Days reserve for "me" running in modest mode. EVEN If I fully discharge the bank and charge with Genset back to 100%, that's done within a day and I have 10 days of juice that requires no input. HOW MUCH is 10 Days worth of Gas/Diesel/LPG or NGas ???
Now I look out from the ridge here and a LOT of folks have No Grid Power (major winter storm underway and lines are down) and here I sit with 70% in my bank and No Worries that I'll run out and IF my batteries get to disconnect point, the Genset kicks in and charges my battery bank while also passing through to house concurrently.... No Grid Power at my home and there never will be while I live here.
Lastly, Gasoline & Diesel do sour over time and becomes useless & gummy if not used up... Natural Gas or Propane fuelled gennies that is not a problem but NG is not everywhere and hookups are a bitch ! LPG is easy enough but is subject to really volatile prices as it is a BYPRODUCT of Gasoline Refining and you have to go get it when you need more which may not always be possible if you run out and shit is happening that we have no control over.
I run 1300AH/33kWh of LFP Battery. Solar can charge it on a sunny day but in winter am subjected to days without sun (really north). 1300AH = 10 Days reserve for "me" running in modest mode. EVEN If I fully discharge the bank and charge with Genset back to 100%, that's done within a day and I have 10 days of juice that requires no input. HOW MUCH is 10 Days worth of Gas/Diesel/LPG or NGas ???
Now I look out from the ridge here and a LOT of folks have No Grid Power (major winter storm underway and lines are down) and here I sit with 70% in my bank and No Worries that I'll run out and IF my batteries get to disconnect point, the Genset kicks in and charges my battery bank while also passing through to house concurrently.... No Grid Power at my home and there never will be while I live here.
Lastly, Gasoline & Diesel do sour over time and becomes useless & gummy if not used up... Natural Gas or Propane fuelled gennies that is not a problem but NG is not everywhere and hookups are a bitch ! LPG is easy enough but is subject to really volatile prices as it is a BYPRODUCT of Gasoline Refining and you have to go get it when you need more which may not always be possible if you run out and shit is happening that we have no control over.
Weeeell---------I got my answer!
Just a couple more comments. Yes, diesel fuel does have an expected time life but I have a 500 gallon home heating oil tank in my basement that will not sour. Annual expected power outage history should be considered when making a battery decision. As to my daughter, her natural gas powered generator surely does not require much service other than maybe changing the oil once every year or two. Heck, I change my Crusader 454 boat engines' oil every other year with no problems over the last 20 years doing so. My car gets oil changes every 3,000 miles or so.
Just a couple more comments. Yes, diesel fuel does have an expected time life but I have a 500 gallon home heating oil tank in my basement that will not sour. Annual expected power outage history should be considered when making a battery decision. As to my daughter, her natural gas powered generator surely does not require much service other than maybe changing the oil once every year or two. Heck, I change my Crusader 454 boat engines' oil every other year with no problems over the last 20 years doing so. My car gets oil changes every 3,000 miles or so.
PreppenWolf
Solar Addict
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I honestly don't understand people who own solar without batteries. Why sell your power to a supplier who turns around and sells it back to you for more? Why be reliant on the grid and not be independent?
OffGridInTheCity
Solar Wizard
Batteries don't make noise 
Hedges
I See Electromagnetic Fields!
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Most of us have/had solar without batteries because we had net metering, supplier credits same as he charges us. Or time of use differences.
Even when time of use rates varied 3:1, with PV costing $0.025/kWh and cheapest batteries $0.05/kWh, better to just bank power in the grid.
Previously, batteries (lead-acid or commercial lithium) cost $0.25 to $0.50/kWh, as much or more than grid rates.
Only now, with cheaper lithium batteries and the killing off of net metering does battery make sense for grid-tie applications.
Even when time of use rates varied 3:1, with PV costing $0.025/kWh and cheapest batteries $0.05/kWh, better to just bank power in the grid.
Previously, batteries (lead-acid or commercial lithium) cost $0.25 to $0.50/kWh, as much or more than grid rates.
Only now, with cheaper lithium batteries and the killing off of net metering does battery make sense for grid-tie applications.
Delmar
Solar Addict
I can't stand the noise from a generator, and they have to spin at full speed even to power a night light.Batteries don't make noise
Will reconsider if/when inverter generator technology improves for larger units. For my Mom I installed a Generac 14KW that grunts to start a 3-ton AC , otherwise the other 99% of the time it has minimal load. But I now have a convenient source (away from my ears) to recharge my golf cart
Attachments
No dispute here other than cost. 33KWH battery at $0.50/watt is $15K and that is just for the battery! How much additional cost for the electronics?
I have net metering
svetz
Works in theory! Practice? That's something else
Batteries are a stop-gap until you can use your EV.
In some locations (e.g., California) the utility has TOU rates that make having battery backup for the highest rates economically acceptable.
With the 30% federal incentives for ESS, it's even that much more attractive. Massachusetts (and other places) have programs that pay you (rather than peaker plants) to export power at peak times, which can make it very attractive.
As battery prices continue to fall, they become even more attractive economically. At some point they'll fall so low it won't make sense to stay on grid anymore.
In some locations (e.g., California) the utility has TOU rates that make having battery backup for the highest rates economically acceptable.
With the 30% federal incentives for ESS, it's even that much more attractive. Massachusetts (and other places) have programs that pay you (rather than peaker plants) to export power at peak times, which can make it very attractive.
As battery prices continue to fall, they become even more attractive economically. At some point they'll fall so low it won't make sense to stay on grid anymore.
Doggydogworld
Solar Enthusiast
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Generator is generally cheaper for occasional backup, LiFePO4 batteries cheaper for daily use. So if you're off-grid, or on-grid with high electricity rates and uncharitable net metering policies, batteries can make economic sense. Especially if taxpayers foot part of the bill.
Hedges
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Batteries may be cheaper than the spread in utility rates.
But, if you can get away with exporting 3kWh from PV during off-peak to earn credits for 1kWh on-peak, that may be as good or better deal.
Likely to depend on available area for panels, and if you can get away with installing panels producing more kWh/year than your consumption.
Once we have both TOU rates and export credit just 25% of import, then the above approach doesn't look good. Have to export 12 kWh to get back 1 kWh. Batteries are then the way to go (but only if you don't pay $0.50/kWh of cycle life, about where I peg batteries like LG RESU.)
PreppenWolf
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I paid $15k to build my own battery banks and I have 105kWh of storage.
I know you think you have your answer now but...
After spending the summer in my 5th wheel with no solar going through too much gasoline I finally got my RV solar hooked up while I build my big system. PEACEFUL! Wished I'd done it months before. As others have mentioned, QUIET and dependable power is a huge part of it. I ran my generator zero % from 9-15 until 12-7.
Next, when off-grid is a financial as well as functional necessity & with a minimum of 250 full sunshine days a year (SW Colorado) solar AND batteries make the most sense. BTW the majority of the rest of the days are partial sunshine with enough to charge...most days.
Whether diesel, LP generator or solar...if your going to live off-grid you have 2 choices go with batteries one way or the other...or do without power.
BTW, getting the grid within 900' of my house was over $35k...& then they stopped, leaving the rest to me to build. Buying 54-390w bifacial panels, racks, 10 LFP batteries, 3 inverters & a dual fuel generator has me coming out at break even with no monthly for eternity.
Lastly, going off-grid requires redundancy. I will likely add a larger LP diesel generator at some point & I will attempt to fire my radiant heat with electricity but with an LP backup tankless HWH. I am also putting in a central fireplace.
I will always keep my 1,000 gal LP at 70% or more as well as 500 gal of diesel fuel as well as 10-20 chords of wood. I am NOT a prepper but I do believe in being prepared & as self-sufficient as possible.
P.S. I plan to change my oil in my batteries only once every +20 years. ?
After spending the summer in my 5th wheel with no solar going through too much gasoline I finally got my RV solar hooked up while I build my big system. PEACEFUL! Wished I'd done it months before. As others have mentioned, QUIET and dependable power is a huge part of it. I ran my generator zero % from 9-15 until 12-7.
Next, when off-grid is a financial as well as functional necessity & with a minimum of 250 full sunshine days a year (SW Colorado) solar AND batteries make the most sense. BTW the majority of the rest of the days are partial sunshine with enough to charge...most days.
Whether diesel, LP generator or solar...if your going to live off-grid you have 2 choices go with batteries one way or the other...or do without power.
BTW, getting the grid within 900' of my house was over $35k...& then they stopped, leaving the rest to me to build. Buying 54-390w bifacial panels, racks, 10 LFP batteries, 3 inverters & a dual fuel generator has me coming out at break even with no monthly for eternity.
Lastly, going off-grid requires redundancy. I will likely add a larger LP diesel generator at some point & I will attempt to fire my radiant heat with electricity but with an LP backup tankless HWH. I am also putting in a central fireplace.
I will always keep my 1,000 gal LP at 70% or more as well as 500 gal of diesel fuel as well as 10-20 chords of wood. I am NOT a prepper but I do believe in being prepared & as self-sufficient as possible.
P.S. I plan to change my oil in my batteries only once every +20 years. ?
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