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coopec43 · 13-01-2021, 01:45

There's undoubtedly stacks of threads on solar panels but I just want advice on a couple of panels I am about to buy.

I only have room on the aft cabin for panels 1 meter X .5 meter. ( I plan to wire them in series to give 24V) I am following advice proffered on this forum to go rigid panels.

Apart from two panels I need a "solar charge controller"? I'll look at the mounts they sell but is there anything else?

https://www.ebay.com.au/itm/Renogy-8...frcectupt=true

Thanks in advance

HeinSdL · 13-01-2021, 02:13

Yes, you need a controller, can be the PWM or the MPPT, MPPT especially if the panels are in series and the batteries are 12V. I have Renogy panels and their controller (started with PWM with the two panels in parallel then changed to their MPPT with the panels in series). I think the panels are OK and the controllers apparently are basic. Out of the max 200W generating capacity I have seen max probably around 130W which I find slightly disappointing but not sure yet if other makes do a better job.

coopec43 · 13-01-2021, 02:18

Thanks for that HeinSdL

I realise I have posted this thread on the wrong forum now. Never mind, I guess you guys will have all the info I need.

I am going to wire them up in series because the yacht is 24V.

coopec43 · 13-01-2021, 02:27

Having read this I think I'll go for a MPPT Controller.

An MPPT controller will yield higher returns compared with a PWM controller as the panel voltage increases. ... A PWM controller will not harvest any additional energy, but an MPPT controller will harvest an additional 11.1% (4 / 36) from the 180W panel

https://www.solar4rvs.com.au/buying/...oller-regulat/

I plan to put more panels on the fore-cabin. Should I take that into account when choosing the MPPT Controller?

jhilley · 13-01-2021, 09:23

Yes, you will have to get a Charge Controller with greater Current (Amps) capacity. Definitely go with MPPT Controller

FionaJC · 13-01-2021, 09:23

Quote:

Originally Posted by HeinSdL

Yes, you need a controller, can be the PWM or the MPPT, MPPT especially if the panels are in series and the batteries are 12V. I have Renogy panels and their controller (started with PWM with the two panels in parallel then changed to their MPPT with the panels in series). I think the panels are OK and the controllers apparently are basic. Out of the max 200W generating capacity I have seen max probably around 130W which I find slightly disappointing but not sure yet if other makes do a better job.

I have had MPPT and PWM, multiple panels, Poly & mono crystalline, flexible and rigid. I have just had my entire solar system stolen and the insurance has paid up. I am also an electronic engineer so this is what I have chosen as my perfect package.

Epever MPPT 30A Controller. 2 x German Monocrystalline semi flexible 80W with ETFE. 2 130A AGM batteries. To charge from shore and emergency bank 110Ah x2 (Which is charged through alternator with Adverc and VSR. Tis then goes through a Renogy 40A DC-DC charger. I have an EDECOA pure sine 2.5Kw inverter and a 1Kw electric start generator.I have a drawing if you like with changeover switches relays etc.

Its all UK sourced along with my new GSM alarm 120db sirens and strobes.

Experience is a great thing, it enables you to make a different mistake next time until you get it right.

Indefatiguable · 13-01-2021, 09:42

Hey,
I live off-grid on solar only in wisconsin.

Renogy panels are great. HQST are literally the same thing (even same factory) but cheaper.

Every other type of renogy product I've used (charge controllers and batteries) are total junk - I cannot recommend strongly enough steering toward a diff manufacturer. Victron energy charge controller is great, batts are up to you, unless you're near me then blain's f&f marine dual purpose AGM are almost masochistic in their ability to take abuse (temp extremes, repeated over discharging and under charging) and keep functioning as expected.

FionaJC · 13-01-2021, 09:52

Quote:

Originally Posted by Indefatiguable

Hey,
I live off-grid on solar only in wisconsin.

Renogy panels are great. HQST are literally the same thing (even same factory) but cheaper.

Every other type of renogy product I've used (charge controllers and batteries) are total junk - I cannot recommend strongly enough steering toward a diff manufacturer. Victron energy charge controller is great, batts are up to you, unless you're near me then blain's f&f marine dual purpose AGM are almost masochistic in their ability to take abuse (temp extremes, repeated over discharging and under charging) and keep functioning as expected.

Victron is great but pricey and sometimes doesnt give you the higher A on chargers. I like a small portable 240-12V 40A 7 stage charger which has to go through a DC-DC charger to get the voltage up for AGM.

I agree about AGM I kill 3 lead 110A acids every winter but the weight! I did look at lithium but the price is too high and I dont like the charge/discharge rules. I still love my boat, I dont want to set fire to it yet".

ikanode · 13-01-2021, 10:05

Quote:

Originally Posted by FionaJC

I did look at lithium but the price is too high and I dont like the charge/discharge rules. I still love my boat, I dont want to set fire to it yet".

The half dozen or so various lithium chemistries have very different fire risks from very low to very high. Research LiFePO4--that's the chemistry used with solar.

Indefatiguable · 13-01-2021, 10:17

Aye yeah I run a "48v" array just to get the amps down for the victron, was running everything in a row for the renogy controller. It's hard to measure exactly the gains between the two when daylight is the span of a cup of coffee though lol. It seems to be the difference between "not enough" and "enough" with same panels though.

I've been wanting and watching lithium battery tech develop, right now I don't think it's a mature enough thing for me to spend on but at the rate things are going maybe next time or time after.

FionaJC · 13-01-2021, 10:24

Quote:

Originally Posted by ikanode

The half dozen or so various lithium chemistries have very different fire risks from very low to very high. Research LiFePO4--that's the chemistry used with solar.

I did but it needs BMS and still works out more than AGM taking it into account with discharge % and life. At least you only have to lug them to the boat once every few years as opposed to annually with Lead Acid.
.

philiosophy · 13-01-2021, 13:46

All this talk of replacing Golf Cart Batteries every year has me confused. I am no expert but I am getting about 5 years out of my Trojon T 105s. I am by the way living on the hook always for the last ten years excluding the last ten months of Tasmania in a funky little Marina hiding from Covid. Seems to me...Battery abuse. Not keeping the water up, insufficient Solar or what ever type charging system and possibly improper wiring.

I DO HAVE A QUESTION MAY IT PLEASE THE COURT...
A Mexican Electrician named Victor in La Paz Mexico once told me " Instead of Equalizing your Bank every couple months...Discharge them once a year"
I think that makes sense but would like those of you who wish to weigh in.
Thanks...Ohhhh Baby what am I getting myself into...Cheers

Mr B · 13-01-2021, 14:17

Quote:

Originally Posted by coopec43

There's undoubtedly stacks of threads on solar panels but I just want advice on a couple of panels I am about to buy.

I only have room on the aft cabin for panels 1 meter X .5 meter. ( I plan to wire them in series to give 24V) I am following advice proffered on this forum to go rigid panels.

Apart from two panels I need a "solar charge controller"? I'll look at the mounts they sell but is there anything else?

https://www.ebay.com.au/itm/Renogy-8...frcectupt=true

Thanks in advance

Look for solar panels on ebay with out asking for renogy,
Two firms in Melbourne sell them, About the same size and much more watts,
They come with Controllers on most of them,

These are 500 watts, Mono, From ebay in melbourne, $324-00 Delivered,
Came with 2 x 2 into one MC connectors and an 40 amp controller,
But I put a 80 amp controller on mine,
But they are now cheaper than what I paid for them,
The controller automaticall picks up 12 or 24 volts and charges accordingly,

boatpoker · 13-01-2021, 14:42

Quote:

Originally Posted by FionaJC

Victron is great but pricey and sometimes doesnt give you the higher A on chargers. I like a small portable 240-12V 40A 7 stage charger which has to go through a DC-DC charger to get the voltage up for AGM.

I agree about AGM I kill 3 lead 110A acids every winter but the weight! I did look at lithium but the price is too high and I dont like the charge/discharge rules. I still love my boat, I dont want to set fire to it yet".

I've lived aboard since 1994 and you've killed more batteries in two years than I ever have. What are you doing to them ?