One of friends from Northern California is looking to add storage. Is it beneficial? How to evaluate it and are there any calculators? I also posted this question here http://renewableelectron.com/questio...ng-rooftop-pv/
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Is it economical for a home owner to add storage to already existing rooftop PV?
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Is it economical for a home owner to add storage to already existing rooftop PV?
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How does storage reduce your cost of electricity? If you are looking at using batteries to shift demand under a TOU plan, I think it might make sense someday, but not under the residential tariffs that exist today.CS6P-260P/SE3000 - http://tiny.cc/ed5ozx -
Based on the current battery technology and costs unless you have a lot of power outages or can save a lot of money by offsets the high cost of the POCO's power through a TOU plan the payback for any home energy storage system is very long and IMO not worth the investment until the price comes down and the output (kWh) goes up.Comment
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If you are net-metering, then I doubt it would ever make sense economically. If your grid goes down a lot, it may make sense for your lifestyle, but it is still not economic.
I have a neighbor who is net-metering, They have no batteries. They seem to be content with one or two power outages every month. They have no intent to ever get batteries.
If you are off-grid and you are discussing expanding an already existing battery bank. That is a different kind of discussion.
4400w, Midnite Classic 150 charge-controller.Comment
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Until rates reach $1.10 per KWh, battery backup will COST you money (replacing many expensive batteries every 8 years)Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-ListerComment
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Originally posted by Mike90250 View Post... (replacing many expensive batteries every 8 years)
4400w, Midnite Classic 150 charge-controller.Comment
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Originally posted by organic farmer View Post
Why would anyone choose to replace their batteries every 8 years?
What is the lifetime for any type of EV battery? Probably much less than 8 years and that is what is being advertised for these home systems.Comment
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Originally posted by organic farmer View PostWhy would anyone choose to replace their batteries every 8 years?
Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-ListerComment
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Originally posted by Mike90250 View PostNot actually a choice, it's when they eventually fail and go bad, unless it's a bad design and the batteries fail year 2.
So I did some quick calculation and if it can delivery 6.4kWh every day for 10 years that came to about 23400kWh. For me to purchase the same amount of power at $0.11/kWh (that price actually is lower now for me than 8 years ago) would only cost me ~ $2600. I seriously doubt that battery will ever cost $2600 or less to install.
So even with all of their claims, it would never be a good investment for anyone that pays $0.15/kWh or less. And that is assuming it only costs $3500 to install one.Comment
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Originally posted by starsun View PostOne of friends from Northern California is looking to add storage. Is it beneficial?
-have frequent and costly/dangerous power interruptions
-are no longer allowed to backfeed the grid
-are paying astronomical rates for power without grid tie
-cannot get on the grid (i.e. far from power lines)
Then it might make sense. But for someone on the grid in (say) Sacramento - it doesn't make economic sense.
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From talking with my neighbors, it seems that first-time batteries last between 10 and 15 years.
Among my neighbors, the shortest battery lifespan has been 10 years, when one guy allowed his batteries to freeze [a toilet ran all night, which drained his batteries, once they were flat those froze].
The shortest lifespan is 10, the longest is 15 years. I have neighbors who have been off-grid 30+ years.
4400w, Midnite Classic 150 charge-controller.Comment
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Originally posted by organic farmer View PostFrom talking with my neighbors, it seems that first-time batteries last between 10 and 15 years.
Among my neighbors, the shortest battery lifespan has been 10 years, when one guy allowed his batteries to freeze [a toilet ran all night, which drained his batteries, once they were flat those froze].
The shortest lifespan is 10, the longest is 15 years. I have neighbors who have been off-grid 30+ years.
As for any Lithium type chemistry the lifespans maybe longer but at a much higher up front cost which equates to a very expensive way to generate power and being much more than FLA with its shorter life.Comment
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One online retailer charges $4500, so that's $4500 / 23400kWh = $0.19 /kWh for storage if you are an electrician and install it yourself onto a system that can already handle it.
With the ITC, it's 30% less, or $0.13.
Hawaii's considering offering another 25%: http://www.thestate.com/news/busines...e74562142.html
That would bring the price down to $0.09.
That very well might make sense in Hawaii.
http://arstechnica.com/business/2015...lls-in-the-us/ quotes the installed cost of a powerwall plus inverter (presumably solaredge 7600?) as $6500. If a solaredge installed is $2000, that suggests the installed price of a powerwall is $4500. So maybe the estimate above is valid for non-diy, too.Last edited by DanKegel; 05-07-2016, 09:52 AM.Comment
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Originally posted by DanKegel View PostOne online retailer charges $4500, so that's $4500 / 23400kWh = $0.19 /kWh for storage if you are an electrician and install it yourself onto a system that can already handle it.
With the ITC, it's 30% less, or $0.13.
Hawaii's considering offering another 25%: http://www.thestate.com/news/busines...e74562142.html
That would bring the price down to $0.09.
That very well might make sense in Hawaii.Comment
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Updated my post with an installed price.
Musk has a bit of credibility these days:
http://m.csmonitor.com/Science/2016/...r-SpaceX-video
That's three successful booster landings so far.
Apropos warranties: the Nissan Leaf battery warranty is eight years,
http://www.nissanusa.com/electric-ca...range/battery/
so your estimate seems reasonable.
Why do you say gamble? Even at 8 years, that's $0.11 cents/kWh, which might still sound good in Hawaii.Last edited by DanKegel; 05-07-2016, 10:02 AM.
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Originally posted by SunEagle View Post
Those must be some very interesting battery systems. I am not saying I know all about off grid and how to keep a system happy and long life but most FLA battery manufacturers do not warranty life spans ...
4400w, Midnite Classic 150 charge-controller.Comment
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