₦airaland Forum

abunafiu2:
Dear chief GeorgeD, you were about to give us a review of your solar water heater system.
kindly do sir

prof,
sorry i've been occupied with work. as this is highly overdue i will now go ahead and
give my review.

NiyiOmoIyunade:
This is a bit of a controversial topic.

External cooling is not generally required for the MorningStar because it has a robust heatsink installed, HOWEVER, external cooling ensures that the CC runs really cool under all operating conditions, ensuring optimal performance and long life of the internal electronics.

Unbeknownst to most people, the MorningStar MPPT CCs actually derate current at heatsink temperatures above 80°C - this kind of temperature is not uncommon in the tropics (read Nigeria) in poorly ventilated indoor installations hence MorningStar published a 16 page TechTip on the subject of temperature and cooling.

Using the TechTip manual, it is possible to perform the fairly complicated calculations to determine if one needs to incorporate external cooling in his scenario - in my case, when I have my blower fan in operation, the CC heatsink is only slightly warm to the touch but with the fan off, hot enough to burn one's hands. At the very minimum, additional cooling will help secure long life for the CC's internal electronics as they face a lot less thermal stress.

I will reproduce a few relevant pages from the TechTip manual below;

niyi,
in my own particular case, i've never really had the need to incorporate external cooling with
my tristar mppt cc. warm to the touch, yes. burning my hands, no. but maybe i've been particularly
lucky or maybe i've always had the good fortune of installing in airy environments.
going forward i hope to pay closer attention to my heatsink temperatures but in hindsight i can't
recall seeing anything above 50 celcius even at max amps throughput.

NiyiOmoIyunade:
Find a blower fan to provide additional cooling to the MorningStar's heatsink - experiment with a normal house standing fan for starters and report back what you see performance wise.

niyi,
an external fan for the morningstar?
that's certainly food for thought.

all,
its been more than a year now since I started using my solar water heater.
in the next couple of days I will be doing a review of the journey so far.
a few surprises and a lot of flaks too. it has been anything but a dull
experience.

davodyguy:
@GeorgdD

I just your set up 8 years ago. What happened to this set up equipment?

Technology has really evolved and im sure your CC and Inverter now have display screen rather than volt meter
www.nairaland.com/attachments/298210_DSC_0022a_jpg0b3c36eca1ede356c7dbfcddc43c9193www.nairaland.com/attachments/298213_DSC_0023a_jpg1e47e991b869602a1aecd66e841bc613www.nairaland.com/attachments/298214_DSC_0024a_jpg383e6d7974634ccd8af5c745bd9b40af

davodyguy,
lolz! these are throw back pix of the early years in my journey to energy freedom.
ah! the joys of the internet, a place where memories never die!

for starters, that pwm cc in the first picture served its time well without issues. after
being in the cooler for a couple of years, it is now producing much needed juice for a reputable
medical doctor in benin.
the 5kva prostar inverter in the second picture blew up without warning one fateful morning after
working all night. i had earlier shut down it down to cool off in the morning and when i went back
a few hours later to put it on i heard a loud bang and that was the end. the local dealer whom i
bought it from wasn't too excited when i took it back to him for repairs, citing lack of available
spares, support, etc. well, that shouldn't have come to me as a surprise - afterall, what do you
expect from a chinese made mid-range product?
ok, the batteries were zenith 200ah and lasted about 5yrs give and take. i was so impressed with
their performance that i decided to replace them with their 260ah senior cousins which i'm using
till date.
as for the 5kva binatone stabilizer, i guess it just couldn't cope with the huge power draw from
both the inverter and house loads that it caved in and went into early retirement...

i could go on but that would mean writing a whole book on my long journey into renewables...

Barezzi:
Plenty on google...

1. https://earthxbatteries.com/wp-content/uploads/2016/07/SLA-vs-Lithium-Ah-AN1506_New.pdf
2. https://www.victronenergy.com/blog/2015/03/30/batteries-lithium-ion-vs-agm/

barezzi,
thanks for the links. believe me, i read every one of them.
the first link dwelt more on comparing starter batteries to lithium. at a capacity of 1:3 that may be
understandable. however, the victron write-up spoke more to my practical scenario of agm vs lithium
and seems to make more sense.
interestingly, i see that the writer also came up with a price point difference of 3.48 times the price
of agm even at 80% dod (lithium) vs 50% dod (la).
verdict: from a cost perspective, lead acid (la) still carries the day.

bigrovar:
Energy storage is at the mid way point of its transition from Lead Acid due to pressure to find a more sustainable means of generating energy. I honestly see lithium to be a stop gap technology that might soon be superseded as more research money is thrown at solving the energy storage problem. Lithium is still a rare earth material available in very few places on earth. Even if the technology stabilises I expect price would go down up to a point thanks to technology and then shoot up as the low price drive demand .. and that demand would eventually outstrip the supply of lithium. I strategy is to sit and wait and see how it all pans out. The high cost of Lithium now is what is funding many of the research into making it a stable commodity and the raise of electric cars will put more pressure into pushing down price of energy storage and lead to the creation of turnkey all in one solution. My next major upgrade will still be lead acid based probably see what the next 5 years will hold.

bigrovar,
it's really the big energy conundrum playing out all over again. i definitely think the future
belongs to some other storage medium besides lead-acid. but whether lithium is the answer is
what i've been trying to convince myself about. unfortunately, all the replies gotten so far fall
short of that basic answer. emotions? yes. sentiments? yes. hard facts backed by sound
financial analysis? zilch!

Barezzi:
@GeorgeD1,
If i remember correctly, the conversion is not 1:1 It's more like 3:1
A 300Ah Lead Acid (LA) battery bank is roughly equivalent to a 100Ah Lithium bank.

Your current LA capacity is roughly equivalent to a 260Ah Lithium bank... about N6m using your example.

Remember that your 780Ah bank has a usable capacity of 390Ah. A 300Ah Lithium equivalent should give you better value.

Correct me if i'm wrong @chris81964/dapsyra, you can grow your Lithium bank gradually. Start with 100Ah, and grow to 300Ah at anytime.
Unlike LA where one is limited to a max 3-month window to add new batteries.

barezzi,
this is getting quite interesting, isn't it? if 300ah for lead-acid equals 100ah for lithium it then
means we have to ultimately change the way we calculate our power fundamentals, i.e p=iv.
unfortunately i'm yet to see any documentation in support of this. i'd be happy if you could give
any references. at least that would be a good starting point.

NiyiOmoIyunade:
I think Oga GeorgeD tried to account for the differences in AH capacity requirements between Lithium vs. Lead Acid - he derated the Lithium AH requirement vs Lead Acid by 50% - only issue Oga Chris pointed out was that he chose SimpliPhi as his Lithium battery representative case which he deemed too expensive and non-representative of the average Lithium price.

It appears you want to derate the AH for Lead Acid vs Lithium comparison by a factor of 2/3rds and I assume this makes sense for a max daily 30% DoD scenario for a Lead Acid battery to achieve maximum cycle life. Oga GeorgeD appears to prefer a max daily 50% DoD assumption which is in line with what most people can practically afford to do.

The point I am making is that Lithium batteries are not invincible - care has to be taken in selecting an appropriate battery technology to use for any scenario especially so given their steep purchase price.

niyi,
you echoed my thoughts exactly. i like to think of myself as a very practical person (maybe it has a lot
to do with my kind of profession), so i work with hard facts and not just theories. my analysis for battery
bank sizing had a typical scenario for 50% dod which you aptly stated in your comments.
well done.

hello niyi, pranil, chris81964, dmerciful, et al,

so i've been doing some thinking around this whole lithium battery thing and i'm still
struggling to see how present day costs justify the whole excitement it seems to be
generating. take a typical scenario: a 3.5kwh 48v simpliphi power lithium ferro phosphate
(lfp) battery costs about 1,550,000 naira on a popular solar website (names withheld).
using our usual piv power calculation, this translates to 72.9ah at 48v. if i want to make up
a bank of 780ah like i have presently, i will need about 10 units of this lithium battery
making 72.9ah x 10 or 729ah at 48v or 35kwh. this will set me back a whopping 15.5million
naira! even if i decide to do the smart thing and aim for 100% dod, i can only reduce this
cost by half but that will still be unacceptable at 7.25million just for batteries.

now flip this around and lets do the maths for traditional lead-acid agm batteries.
again, i want to build a bank of 780ah batteries and i decide to visit yet another popular solar
website. i get trojan solar agm battery 12v 205ah for about 185k each. i would need at
least 16 units to reach my bank size goal. adding up at 48v this translates to a total 820ah.
which is 39.360kwh (playing up the lithium trick) and at a cost of 2.96million. at a glance
this is less than one-fifth of the cost for lithium with a significantly higher storage.

from a purely economic view point, it wouldn't make sense for me to ditch traditional lead-acid
in favour of lithium when i can get more for less. besides the phantom dod cycles, its lighter
weight plus the fact that you can bypass the usual bulk-absorb-float stages, what other
features does lithium has going in its favor to justify such humongous investment?

abunafiu,
prof, true talk. and not only batteries but cuts across the whole array of
solar accessories including charge controllers, inverters and panels.
inferior products will kill any industry faster than ebola kills its victims.

spyglaxx:
I hate inverters. I power everything directly from the battery. No energy to waste

hello spyglass,
those of us using inverters do so not necessarily because we 'love' inverters
but because of the convenience it provides.going the dc route may sound cool,
I.e no extra cost of inverter purchase, no power losses arising from stepping up
to a higher voltage, etc but when it comes to getting actual dc equipment to work
with your system, that is where the nightmare begins.besides that, the size of
wires you need for a dc only household would be like triple the size of wires
needed for ac.then you have to deal with availability of dc spares and the rest.
for ac however, once you get your inverter, every other thing falls into place.

dmerciful,
that is serious food for thought but at the end of the day I guess its a
choice we all have to make one way or another.

NoMoreTrolling:
lol, Kpele!!

I am almost dreading the months to come, as it's gonna be rainy season in Lagos, with just 3 sun hours average per day

I use the following chart:

this is one of the major challenges of solar - cloudy/rainy weather. however, with proper
system sizing, it can be easily overcome. that is why the rule of thumb for an ideal battery
bank size is 3 days minimum backup. this takes care of days when there is less than adequate
sunshine, rainy weather and total blackout just like dapsyra experienced in abuja recently.
but as always, the drawback seems to be cost. who can afford to buy so many number of batteries
to achieve that level of autonomy? and what about the solar panels that goes with it?
too many questions but few answers...

all,
i think what ola is doing should be commended. whether gift card or no gift card,
amazon or ebay, his source of supply is irrelevant here. the fact that he has chosen
to transfer the cost savings to eventual end users rather than making a kill in huge
profits is worthy of emulation. in this light, other vendors here should carefully
examine their pricing strategy going forward or risk being put out of business.

p.s: this is a candid advice and shouldn't be misconstrued as a threat.

niyiomoiyunade,
you're very much on point. temperature compensation is a very critical part of
battery charging that most of us take for granted. not only are the chinko ccs
guilty of this, even the so-called budget inverters err greatly in this regard. in
so many words, you have just identified one of the major causes of premature
battery deaths in renewables. but the question is, will peeps listen?

NiyiOmoIyunade:
Please I need a contact for solar water heater
(100 to 200Litres) capacity for a building project. The Protek guy I found had only 300L tank capacities
available.

Appreciate any help from the honorable members of the house

it seems you may be in luck after all.
check out the konga link below and see if what they have matches your expectation:

https:///non-pressurized-solar-hot-water-heater-2523935

niyiomoiyunade,
unless your client's roof is concrete, i wouldn't advise a direct mount
even for a 200 liter capacity water heater. i don't really know why he's
avoiding getting a second tower for the water heater but if cost is the
overriding reason, he can just modify his existing fresh water tower
(at a little added cost) and place the water heater under the fresh
water tank.

niyiomoiyunade,
it seems like solar water heaters have mysteriously disappeared from the market
within the space of one year. my advice is to go for the 300 liter capacity that is
available.Besides, when it comes to solar water heating, bigger is certainly better.

niyiomoiyunade,
in my own opinion, 14.2v seems a more plausible setting given the xteristics of lead-acid that
we are all familiar with but again, the manufacturer may know something more about his own
product that we don't hence their seemingly lower absorb voltage recommendation.

bodejohn:
Dear friends,

I have the following items available for sale.

12/24/48V 45Amps TriStar MPPT CC complete with displays - 2pcs


Items are in good condition and comes with 3 months warranty.

Location: Ibadan

Contact: WhatsApp only - 09078802022

hello bodejohn,
you've been pushing these two mppt ccs for a while now. is there any particular reason
why you don't want to disclose your offer price? i think pricing is one strong incentive you
can use in wooing any undecided customer who might be interested in patronising your
wares. beyond pictures, affix a price tag and make it negotiable - in case you're worried
that your price would scare away potential buyers.
just my two cents.

[quote author=NiyiOmoIyunade post=65619417]Good day Oga GeorgeD.

While we are at it please would you happen to know what the recommended/ideal absorb voltage for Quanta batteries is.

I have read 13.8volts as the 'freshening charge' on the spec sheet and also the Amaron Quanta website but I struggle to believe this to be true.

In real life I use 14.1v or 14 2v as the absorb setpoint for Quanta batteries at client locations but I always lose some sleep thinking whether I may be overcharging their batteries.


[/quote

hello niyiomoiyunade,
I haven't really used the quanta batteries before so don't have details about the absorb settings.
the amaron quanta website is silent on that spec when I looked up the literature on their website:

https://www.quanta.in/images/pdf/Quantamanual-new.pdf

i'm sure it is the same document you were referring to when you talked about their 'freshening' charge
specification. my take though is that you leave your settings the way they are since apparently your
clients batteries may not be doing badly at all.

pranil:
Quanta Charging rate 25 %

I came across quanta manual which claims max charging rate for 200 Ah quanta AGM is 25 %. If I am reading right it means the 200 AH Qantas can be charged at 50 amps without any issues

Are my observations correct or I am reading it wrong.

Normally I have set the charges at 10 % or max 13 %

anybody has experience using such high currents 9 Life, overheating)

if the values are right then 8 Quanta can be coupled with Ipower/gennex to take advantage of their 140 amps max charge ratings even if the nepa is svailable 4 hours a day

pranil,
actually some high quality agm batteries can be charged at 50c or 50% capacity without
any issues at all. that is one big advantage of agm over gel or flooded and it's why savvy peeps
like us gravitate towards them.

kiekie1:
Congrats .. You can always rely on solar world modules ! Am glad you are happy . Cheer's

kiekie,
i'm afraid its not yet uhuru. until I begin to see harvests of above 25kwh as a routine
and yields of over 6,000 watts I wouldn't roll out the drums for solarworld just yet.

three weeks ago or less, I was still getting performance below 35% capacity which to me
is a shame given the 1st tier acclaim of solarworld modules. when compared with my original
200w suntech panels that I recently disposed off and given the fact that I never bothered
with washing those suntech panels for the over 5yrs I had them installed and yet they
performed excellently year on year, harmattan to rainy season, it leaves me in serious doubt
as to the veracity of solarworld's ist tier claim.

but all the same we will see how it all plays out. first year monitoring report will tell.

today's sun is really something else.

i pray for more sun hours like this for us all.

20.8kwh and still counting!

NiyiOmoIyunade:
Oga GeorgeD1.

Please I have a question - how were you able to sync the output of two MorningStar CCs to just one remote meter? Are you using the MorningStar MeterHub? And if yes does it also allow you to synchronize perfectly the charging behaviour of both CCs

As you may notice from my posted pics, I have been facing challenges getting my two MorningStar CCs to act as one single unit while charging - one CC may be in Absorb while the other is in Bulk even though they are sharing one common battery voltage sense cable - in fact one may drop to Float while the other one then trips off and stops charging entirely.

I feel that if I can get them to be in perfect sync then I would be able to get max juice out of them. I have looked at the MeterHub documentation but I am not yet convinced that it would bring my two CCs into perfect sync.

hello NiyiOmoIyunade,
you're right. i'm using the meter hub. one of its major uses is to allow multiple controllers share the
same meter. it aggregates the output (wattage and amperage) and allows single point control. however,
it won't help you sync your voltages.

I also had similar experience like yours when I started using more than one tristars on the same battery
bank. I noticed that one charge controller always seemed to be ahead in voltage and it would always be
first to enter absorb and float while the other one lagged behind. so after battling with this for a while
I decided to disconnect the battery sense cable from the leading charge controller. by so doing I practically
blinded the erstwhile leading cc and made the former lagging cc the new master. both voltages were now
aligned with just a 0.1v 0r at most 0.2v difference which worked great for me.

NiyiOmoIyunade,
congrats on your harvest.indeed happy times are here at last.

and still on the matter, a snapshot from my own array this afternoon.

credits to juo and his team who came around to wash off the last remaining
harmattan dust and soot from my panels.

truly d sun is the answer!

teamman:
I was going to recommend the BLS series. They work well. Regards

i've been using the battery life saver (bls) for several years now and
it definitely has been positive stories for me all the way.

the bls coupled with other maintenance best practices has ensured
my battery bank continues to perform as new even after 5yrs.

happy new year to the house.

may 2018 usher in enough sunshine on our roofs
and juice to our batteries.

may our cc perform above 100% efficiency and may
our inverters be able to carry all the loads we throw
at them this year.

above all, may we enjoy 365 days of uninterrupted
power regardless of phcn antics!

groundnuts!

DUNKA:
What happened to Mr. Henry the supplier?

nothing happened to him. i guess he moved on to other products
for business reasons.

earthrealm:
are your batts fla or smf?..especially the first set that lasted 7yrs. or the current ones.
kindly state the make/brand/specs

zenith 200ah.
my batteries have always been agm. both the present ones and the set
that lasted 7yrs.
unfortunately they are no longer available in the market.