Newbie looking for advice for a small, beginning system.

[K-Two]

Hi, Im new to the solar power installation world. I have been reading through most of the permanent posts, but I decided to go ahead and get a thread started while I continue to peruse the site. So Im going to first list the components I am planning to purchase, then write about the set up Phases I want to install and then voice my questions and concerns. Thanks for taking the time to help out and ALL tips and advise are welcome!

Renogy 100 Watts 12 Volts Monocrystalline Solar Starter Kit PWM (MPPT20 or MPPT40 are also available for an increase in price)

Renogy 100W Monocrystalline Starter Kit is designed specifically for customers new to solar. The Starter Kit is great for off-grid applications, such as RVs, trailers, boats, sheds, and cabins - providing many benefits, including, but not limited to, quiet power production and grid independence. This solar kit comes with the tools necessary for a new system: a Renogy 100W 12V Monocrystalline Solar Panel, a 30A PWM Wanderer Charge Controller, a 20ft 10AWG MC4 Adaptor Kit, an 8ft 10AWG Tray Cable, and a set of Z-brackets.

The charge controller has been upgraded to Renogy's new 30A PWM NegativeGround Charge Controller the Renogy Wanderer
With the Renogy Wanderer 30A PWM Charge Controller, you can expand your system up to a maximum of 400W
The kit now includes an 8ft 10AWG Tray Cable to connect your charge controller and battery
Ideal output: 500Wh per day can fully charge a 50Ah battery from 50% in 3 hours (depending on the availability of sunlight)
Negative grounding controller ensures the broader off grid applications and safety, especially to be used on a vehicle which has battery negative on the chassis

12V 100Ah SOLAR WIND AGM SLA DEEP CYCLE VRLA BATTERY 12V 24V 48V

2x Signstek 25ft AWG 10 Double Layer MC4 PV Solar Cable Extension for Solar Panels with Solar Male & Female Connector

2x 2009 24v 30Ah military spec aircraft batteries - need to see if they are still capable of holding a charge, but if they can, bonus for later on!!

I would like to have landscape lighting for 2-4 hours each night.

PHASE 1
Front yard
Hampton Bay 590-313 (auto @ nite)
Input 120v AC, 60 Hz, 2.6 A
Output 12v/14v AC (use only 12v MR 16, MR 11, T3 type - 300 W max lamp load...not for use with dimmers
6x 20w halogen bulbs = 120W

PHASE 2
Backyard (remove low volt transformers and use lights connected direct to above system)
Malibu low voltage timing transformer ML88T
Input 120v - 60Hz, 1.0 A max
Output 12v, 88w max
15x 4w landscaping lights = 60 W

Twilight low voltage lighting system CB-150MD
Input 120v - 60 Hz 1.5 amp
Output 12v AC, 60 Hz, 150 watt
6x 20w halogen bulbs = 120W

PHASE 3
16x 23w CFL lights over a distance of 200 yards around yard with wiring already installed.

PHASE 4
front gate (w/ back-up batteries)

I am looking to change all bulbs to LED lighting in stages as we add more to the system over time.

Concerns:
Would someone mind explaining the difference between PWM, MPPT20 and MPPT40 for the panel system, please? From what I understand, the 20 and 40 are more efficient for charging. Right now, I dont mind using the cheaper one until I need something more advanced and learn how the system works to a higher degree.

I am confused and lost when it comes to an inverter, so I need some basic, talk to me like Im a fifth grader education on this. I figure it is a bit different since Im not just going to plug a cord into an inverter for the use I have planned.

Is the panel listed above sufficient to charge the battery? We live in SE GA. Typically mornings and early afternoons are good for sunlight. I would expect anywhere from 6-9 hrs of sun a day.

Does 2-4 hours seem a reasonable time for these types of lights to be on with the 100Ah deep cycle battery described above? If not, what would be required?

Will the distance between the CFLs and landscape lighting significantly affect the system as planned? I understand I will probably need to expand to more panels for more chargability and batteries for longer sustained usage.

The 24v batteries still need to be tested for chargability, but if they are able to hold a charge, do i need a 24v panel to charge them?

I think thats it for now, but thank all of you so much ahead of time for the help.
Best wishes and regards,

Mike

[Logan005]

Wow, You want to run an inverter to convert your 24 volts DC to AC, so you can use a AC to DC converter for your halogen yard lights? Get rid of all halogen lights first. If your yard lights are DC, just get a few24 volt to 12 volt step down converters. make all of your long runs, 24 volts and step down at critical points. If you are checking old batteries to see if they hold charge, your already off on the wrong foot. 16 CFL at 24 watt's is going to require several thousand dollars in batteries all by their selves. and likely 2000 watt in panels, You will want grid tied panels of 250 to 325 watts and you will likely need to up your battery bank from 24 to 48 volts. Does this location have grid access?

[K-Two]

Hey Logan thx for the reponse. I was planning to replace both the halogens and CFLs with LEDs to drastically reduce the power required for the system. It was buried in the previous post after the Phases I wanted to go through. The location does have grid access. Like I said, I want to start small with the Phase 1 as described above after I replace the halogens with LEDs and will replace the other light bulbs as I move through each phase. I have the 2x 24v batteries, but dont know if they can hold a charge, so I plan to purchase a 12v/24v/48v 100Ah deep cycle battery for power storage. I figured if I replaced the 6x halogens with the LEDs just in the front yard to start I'd be able to add more on pretty quick.

[solar pete]

Howdy K-Two and welcome to Solar Panel Talk. I would recommend reading up in the off-grid section, the first thing you need to do id determine the load in watt hours or kilowatt hours (kWh) I see you have made a start on that. Re the batterys are you saying they are 2009 built? if so and if they have not been maintained correctly they will most likely be toast. Day time hours are different to solar isolation hours, most likely you need to work on 4-5 in summer and 2-3 in winter. Re how many panels will be required its hard to say without knowing the daily load, Solar systems are not generally easily expandable and more often that not you are far better off doing it all at once, keep reading and good luck with it.

[K-Two]

hiya Pete. The 24v batteries were free and maintained on a military installation so I figured it wouldnt hurt to see if they can still hold a charge. I plan on purchasing a 12v/24v/48v 100Ah deep cycle battery to start the setup. I will look more into the kWh for the lights, but I plan to replace everything with LEDs as I go. I know what you mean by it will be cheaper to do it all at once, however the panel i was looking at comes with a charge controller expandable up to 400w which Is why Id like to take it slow and learn as I go. Thanks for the post!!

[K-Two]

So heres what I plan to replace the bulbs with and their wattage:

Phase 1
6x 20w halogen bulbs with MR16 5w LED bulbs reducing the required power from 120w to 30w

Phase 2
15x 4w T10 landscaping bulbs with T10 0.5w LED bulbs reducing the required power from 60w to less than 7.5w
and
6x 20w halogen bulbs with MR16 5w LED bulbs reducing the required power from 120w to 30w

Phase 3
16x 23w CFLs with 8.5w LED bulbs reducing required power from 368w to 136w (all of which will be enclosed)

Adding the total watts required for the three different phases equals 203.5w, which is below the 12v/14v AC hampton bay's transformer max of 300w.

The reason I want to complete this in different phases is to make sure I stay under the required watts for the transformer, give myself sufficient time to test the system and also to distribute the cost over a little more time. As previously stated, I ony want to run the system for from 2-4 hours per day, not all night long. Does this make sense? Thanks again!!

[K-Two]

I have ordered and received the components below to start csetting up the system.

1. 1x Renogy 100 Watts 12 Volts Polycrystalline Solar Panel Starter Kit (Ideal output: 500Wh per day can fully charge a 50Ah battery from 50% in 3 hours) that comes with a 20ft 10AWG MC4 Adaptor Kit, an 8ft 10AWG Tray Cable, and a set of Z-brackets.

2. Fuse holder and 100amp fuse for connection from panel to controller

3. 30A PWM Wanderer Charge Controller (comes with above kit)

4. 1x 12V 100Ah SOLAR WIND AGM SLA DEEP CYCLE VRLA BATTERY (can be set up for 12V 24V 48V configurations if required)

5. Kreiger 1100 Watt continuous (2200W peak) 12V power inverter to 120v AC with overload, temperature and short circuit protection, an LCD display for Input Voltage, Output Wattage and Battery Level, a remote control and inline 150 amp fuse. Bought for future expansion purposes.

6. [Part of previous set-up) Hampton Bay 590-313 (light sensor), Input ~120v AC, 60 Hz, 2.6 A; Output 12v/14v AC (use only 12v MR 16, MR 11, T3 type - 300 W max lamp load...not for use with dimmers)

7. All landscaping lights have been replaced with LEDs giving the following power usage per set up phase:

Phase I: 6x 20w halogen bulbs = 120W replaced with MR16 5w LED bulbs reducing required power to 30w

Phase II: 15x 4w landscaping lights = 60 W replaced with 15x T10

[K-Two]

Sun,
Thanks for the post. The battery I purchased is a 100Ah 12v battery. The panel's specs reflected an ideal output of 500 Wh per day fully charging a 50Ah battery from 50% in three hours. I figured since the panel can charge a 50Ah battery brought down to 50% (approx 25Ah) in 3 hours, it should be able to fully recharge a 100Ah battery brought down to between 80% - 60% (guess) for 1-2 hours of use.

I used the following calculations to assume the pv and battery would be sufficient:

(100Ah)(12v) = 1200w
1200w - 210w = 990w still available
990w/1200w = .825 or 82.5% of the battery is still available and only 17.5% needs to be recharged the next day.

If I used the lights for two hours, it would double the discharge percentage to 35%, still leaving 65% (780w) of charge.

Does this make sense?

[SunEagle]

I would not necessarily believe all that is advertised concerning solar panel, batteries, and charge controllers.

IMO that 100watt panel can provide about 5.5amps for a few hours a day but it would be very hard to get 500wh out of it every day.

And if your battery is rated 100Ah then you will need at least 2 of those 100watt panels to get the right charging amps.

[K-Two]

So do you think the initial set up would be okay with only phase I since its only 30w (3amps) and I can work the system up from there?

My plan is to eventually have it maxed out at 400w with 2 100Ah batteries in series for this setup, having all landscaping lights and the gate connected to the system. Lights would on be on a couple hours a day, but the gate would be 24/7.

The next I do maybe from 2x 100Ah batteries in parallel to get more current as a 24v system to power a pond aerator motor, but I want to learn a little more from the process now. Thanks again for the info.

Regards and have a good weekend!

[SunEagle]

If you only have a 30 watt load you could run it for about 10 hours a day using that 100Ah 12v battery. (100Ah x 12v x 25% / 30watt = 10 hr) But a 100 watt panel is not enough to re-charge a 100Ah battery properly back up to 100% in a day.

A 100 watt panel may get you 5.5amp out but that is not enough. It calculate to a C/18 charging rate (100Ah / 5.5 amp = 18.2hr) which is too slow for that battery. You either reduce your battery to a 50Ah or add another 100Watt panel.

[K-Two]

Two questions. Does the same battery drain and re-charge hold true if I only use the 30w landscaping lighting for 2 hours not 10? Second, what is the 25% represent in the first equation

(Ah)(v)(25%)/w = time(in hours). Thanks again for helping me with these calculations. Have a great weekend!

[SunEagle]

If you only use 30 watt load for 2 hours then you have used 60 watt hours. Which would be ~ 5% of a full charge that 12v 100Ah battery can provide (60wh / 1200wh = 5%).

The 25% is the amount that can safely be used of the 100% rating of the battery. A 100Ah x 12v = 1200watt hours. 25% of that would come to 300 watt hours. Using more than 25% of an FLA type battery can shorten the lifespan of the battery.

[K-Two]

Gotcha. So, if the battery has a 5% drain, will take 1/5 of the 18.2 hour charging time as well? If I got another 100W pv panel, the would that cut the charging time in half as well?

[Mike90250]

ready fire aim.

You are dumping your $$ into a bottomless pit. Stop spending money and listen up.
You cannot piecemeal "grow" or expand a system, unless you over buy parts from the beginning.
Buying used/old/expired batteries is a fools errand. The military NEVER gets rid of anything if they can wring anymore out of it.

You FIRST need to define your FINAL loads, then build your system from there, or you will be building 3 different systems and throwing the early version away. each time.
First change out all your lights to LED, then figure your loads.

And remember, if you have grid, every watt you take off grid, costs 10x what leaving it on grid would cost. If you have lots of money, that's fine.

[K-Two]

Thanks for the comment!! All lights have been changed to LEDs. Final load for the setup I want is 204w for 2 hours per day to run all landscaping lighting. However, I plan to build up in phases to the total because I am very time limited. I purchased a FLA, 100Ah 12v battery to use specifically for the landscaping lighting and do not plan to use the military batteries in this system. Thanks again for taking the time to post and have a great day!!