Hi William, I dont do the math based on up front kwh cost, but on lifetime kWh based on the number of cycles per average DOD that are going to be used. I use this same formula to compare all batteries to each other.
Jay Peltz power. For example, a Rolls L16 ex has 3500 cycles at 50% DOD, and it’s a 371 amp hr at 6v or 2.226 kWh Retail is $400 3500 cycles x 1.1 kWh At 50 DOD=3850 kWh $400 / 3850 kWh = $.10 kWh 10 years of 50% cycling daily Compared to say a mid grade US battery, 1400 cycles to 50%, 400 amp hr. 2.4 kWh $325/1680 kWh = $.19 kWh. 3.8 yrs life Compare to say BI $1000 kWh roughly. If you get 10,000 cycles, that works out to same cost. $.10 per kWh. 27 yrs, but will the chemistry actually last that long? However, you have a massive upfront money cost. And for those of us off grid, you can’t really cycle 100%. And many lithium in the fine print don’t want you to charge to 100% daily. Let’s assume you start the generator at 10% and charge to 95%, now your usable amount is actually 85%, not 100%. Cost per kWh goes to $.12. > On Aug 11, 2020, at 6:04 AM, William Miller <will...@millersolar.com> wrote: > > > Friends: > > I am hoping y’all can tell me I am doing something wrong with my arithmetic. > I have registered to purchase Blue Planet batteries and priced the product. > I come up with math that indicates that comparing usable amp/hours to usable > amp/hours, that the Blue Planet is 5 times the cost of a flooded L-16 battery > array on a cost per kilowatt/hour. Can this be true? > > I am using these parameters: > > 1. DOD for flooded L16s: 50% > 2. DOD for Blue Planet: 100% > > I hope I am wrong. > > Also, we often install battery arrays that are upwards of 4,000 AH. For > example, we installed 5,668 of East Penn flooded batteries on a couple of > projects. To acquire the same capacity in Blue Planet would require 9 > cabinets (again 50% DOD versus 100% DOD). Is this correct design? Is it > practical to install 9 cabinets? Does the system detect and compensate for > circulating currents in this many parallel strings? > > Thanks in advance. > > William Miller > > > From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On > Behalf Of Jerry Shafer > Sent: Sunday, August 9, 2020 12:02 PM > To: RE-wrenches > Subject: Re: [RE-wrenches] Best Battery > > Wrenchel have been very happy with all my Blue Planet battery systems, best > battery you will install. > Jerry > > On Sun, Aug 9, 2020, 11:19 AM <drake.chamber...@redwoodalliance.org> wrote: > Hello Wrenches, > > What is the best Li-Ion battery to use with an off grid system? > > Thanks, > > Drake > Athens Electric > > -- > _______________________________________________ > List sponsored by Redwood Alliance > > List Address: RE-wrenches@lists.re-wrenches.org > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > List-Archive: > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org > > List rules & etiquette: > www.re-wrenches.org/etiquette.htm > > Check out or update participant bios: > www.members.re-wrenches.org > > _______________________________________________ > List sponsored by Redwood Alliance > > List Address: RE-wrenches@lists.re-wrenches.org > > Change listserver email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > List-Archive: > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org > > List rules & etiquette: > www.re-wrenches.org/etiquette.htm > > Check out or update participant bios: > www.members.re-wrenches.org >
_______________________________________________ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out or update participant bios: www.members.re-wrenches.org
