Brand new to solar- any suggestions

[Luismclaughlin]

I was originally looking at an EG4 charge controler /inverter combo and going with EG4 3000EHV-48 ad 2. 48v batteries. Then I realized that I didn’t have the money for it. I am now looking at the Victron SmartSolar MPPT 150/100-Tr VE.Can

I am hoping to start off with an AGM 12 volt battery and a few solar panels to start with. We can get by with an 800 watt system.
Here is our load requirements

RV propane fridge 8.4 watts (12 vdc)

4 LED grow lights (168 watts 120v ac)

2 phone charger 36 Watts (120v ac)

Fan 50 Watts ( 120v ac)

Milwaukee Battery Charger (252 watts 120v dc[i may purchase a 12v DC powered one in the future ] )

Coffee grinder ( 200watts 120v AC)

Down the road we plan to add enough capacity for running a washer 4 to 6 loads a week plus several other electric powered devices. That system will probably require anywhere from 3000 to 6000 watts. I would like to purchase a system at the beginning here, where I don’t have to get rid of it and buy something else to upgrade. Will the Victron unit I mentioned work so that I can add to it later? And then change the batteries from lead acid batteries to lithium 48V? We have around $1,300 to work with right now.

 

[murmeister]

I am not familiar with a wide variety of products so I can't speak to the ones you mentioned. As a general piece of advice, I'd say that perhaps you can discard the idea of growing the small system into an all-encompassing system later. Maybe use the small system to truly learn what your needs are and how everything will interact. Then, retire that system or move it to your shop, shed, deer lease... Then, purchase the system you "really want" later on.

 

[Rednecktek]

I'd recommend against the AGM battery. LFP's are cheaper per usable watt hour and have a much longer life span.

You really want to do 2 systems here. The first is a small 1kw with 12v and a few panels to learn what does what and how. When you step up to a real boy system you're not likely to be able to re-use anything. That's OK.

With $1300 you can easily get a simple system thrown together with LFP batteries and used panels. Remember to budget in the lumber cost of mounting everything. The simplest system would be about 600w of panels, an MPP 1012-LV unit, and a bigger LiTime battery in the 200+ amp hour range. Should put you in the $1000-ish range leaving some for lumber, wire, and beer.

 

[Luismclaughlin]

I'd recommend against the AGM battery. LFP's are cheaper per usable watt hour and have a much longer life span.

You really want to do 2 systems here. The first is a small 1kw with 12v and a few panels to learn what does what and how. When you step up to a real boy system you're not likely to be able to re-use anything. That's OK.

With $1300 you can easily get a simple system thrown together with LFP batteries and used panels. Remember to budget in the lumber cost of mounting everything. The simplest system would be about 600w of panels, an MPP 1012-LV unit, and a bigger LiTime battery in the 200+ amp hour range. Should put you in the $1000-ish range leaving some for lumber, wire, and beer.

Thanks so much for the info.

 

[Luismclaughlin]

I'd recommend against the AGM battery. LFP's are cheaper per usable watt hour and have a much longer life span.

You really want to do 2 systems here. The first is a small 1kw with 12v and a few panels to learn what does what and how. When you step up to a real boy system you're not likely to be able to re-use anything. That's OK.

With $1300 you can easily get a simple system thrown together with LFP batteries and used panels. Remember to budget in the lumber cost of mounting everything. The simplest system would be about 600w of panels, an MPP 1012-LV unit, and a bigger LiTime battery in the 200+ amp hour range. Should put you in the $1000-ish range leaving some for lumber, wire, and beer.

Thank you for some direction on what to get.

Are there any recommendations for types of cables connectors etc to purchase to wire it all up? I am guessing I will need to have a cable 50’ long or so to go from my solar panels to the unit. Do the batteries need to stay above a certain temperature.

 

[murmeister]

AGM batteries are rated better than lead acid batteries for the cold. I wouldn't leave them exposed to direct elements but an enclosure should be adequate for most cold environments.

The cable you use depends on how you're going to run it. Will you bury in conduit? Direct bury? String it along poles? 10AWG THHN is good for around 100 feet before voltage drop gets really noticeable. I went with 8AWG buried in conduit to run about 150 feet from my solar array.

Interestingly, I had some 10AWG PV cable that was rated for direct burial (provided by Signature Solar) that I used as a temporary run while setting up my trench and it demonstrated only nominal voltage differences than the 8AWG did. I don't know if it was due to the extra shielding/insulation or if my distance didn't really demand 8AWG. I was surprised to see the thickness difference between the 10AWG rated for direct burial vs the 8AWG THHN. The 10AWG was much thicker.

I was able to get spools of the 8AWG THHN from my wholesale electric supplier for a very competitive price. It was MUCH less expensive than going to a chain box store. Their pricing made me feel better about the "upgrade" to 8AWG.

 

[MichaelK]

Thank you for some direction on what to get.

Are there any recommendations for types of cables connectors etc to purchase to wire it all up? I am guessing I will need to have a cable 50’ long or so to go from my solar panels to the unit. Do the batteries need to stay above a certain temperature.

Do NOT focus attention on minutia like the gauge of wiring, when the big decisions have not yet been made. You are focusing attention on the wrong details right now. What you need to be focusing on right now is what electronics to buy, the size/type of battery, and how many panels you need.

Looking at your loads listed, you may be surprised to find that the inverter you buy will actually be the single largest load that you will need to support. Keep in mind that many of the AiO units have high background idle consumption, that is the power they consume just sitting there, being left on. Some AiO units consume as much as 60-100W idling, which amounts to a 1.4-2.4kWh load if left on 24/7.

A fraction of that comes from quality of design. A good rule of thumb is that for a particular class of inverter, the idle consumption is directly related to how well it was put together. That is, the most poorly designed units have the greatest idle consumption. Another gauge of quality is surge ability, the inverter's capacity to start surge loads like electric motors, that for a fraction of a second, consume 3-5X their running current. Cheaply made inverters can surge for milliseconds. Quality ones for seconds. For running a washer, powered with an electric motor, make sure your inverter is sine-wave.

Echoing the advice of MM, and RNT, you are not likely to expand a starter system into a whole-home system. Not starting out with a 1300$ budget. I'll throw something out there for you to think about. I'm not a fan of 12V. I'll give you an example for a 24V starter system. You will want to graduate to 48V when you are ready to go whole house.

Don't buy 12V panels retail. You get much better deals with larger high-voltage residential panels. Here is a panel dealer within driving distance. He appears to have lots more choice besides the one I'm referencing.

400 watt SOLAR POWER PANELS, new in crate - materials - by owner - sale - craigslist

Wanna make some off-grid power? Well drive to Tennessee, where there's crates full of NEW 400 watt black Hyperion solar panels, A-grade 25 yr factory warranty, $120 each (3 panels MINIMUM...or 2...

lexington.craigslist.org

Two 400W panels: 300$ (wire them in series, and run 10 gauge copper wire back to charge controller)
Four 6V golf-cart batteries from CostCo, 210Ah each: 440$ (4 gauge copper wire minimum, 2 gauge better)
Epever 40A 12V/24V charge controller: 125$ (6 gauge copper wire from controller to batteries
Samlex PST1500 24V inverter: 625$ (minimum 4 gauge copper wire from batteries to inverter; use the same gauge as what's between the batteries)
wiring, fuses, beer: 100$ (Shop at HomeDepot for already cut leftovers. You can get leftover roll ends for 50% off.)
Total: 1590$ Yes, a bit over your budget, mostly the fairly expensive Samlex inverter. It's UL-listed, whereas cheaper inverters are likely not. It will have enough capacity to run your washing machine, and has low background idle, ~19W.

 

[murmeister]

@MichaelK gave the kind of advice you came to this forum for. The experience behind those words should be heeded. When I was deciding on what to get I read on here somewhere that the expenses of today's decisions will be far outweighed by your disappointment in the future (or something like that). I took that to mean I should get what I really want/need today - even if it costs a bit more - and enjoy that decision for a long time to come.

Incidentally, I wish I had purchased more batteries.

 

[RV8R]

Hi @Luismclaughlin

I notice only 1 12vdc load ,,, that is a direction towards design for a 120vdc fridge in my mind





If, you are looking at an inverter always on system ( or standby ), my gut feeling without knowing anything about your needs or future needs would point my towards;

24vdc batteries
24vdc to 120vac Inverter
Expandability when needed


I would need to know more about what you are trying to achieve (eg are you also heating with propane ?).

You are running an inverter for pretty light loads. I run 12vdc for almost everything other than heat & then I have propane.

IMO, the 12vdc / 120vac might be able to be simplified ?

 

[billvon]

Brand new to solar- any suggestions?

OK here's my list.

1) DON'T BUY ANYTHING YET! Wait until you know your loads and what your goals are.

2) If you want to go small (learning system, more playing around than generating power) go 12V. Stuff is cheap and it's compatible with cars/RVs. If you want to generate a lot of power (i.e. upwards of 3000W) start at 48V.

3) Reduce energy use FIRST. As a rule of thumb, every $1 you spend on efficiency reduces your solar system cost by $5.

4) It's possible - but more difficult - to design a system that you can expand later. Batteries you can expand if you are careful. Solar you can expand. Inverters are harder, since small inverters tend to not stack well. Charge controllers are also difficult, but you can add them incrementally. You'll often have to replace the wiring and protection, and that's not that cheap since copper is expensive.

5) All-in-one systems (inverter + charge controller) are a great way to get started. They were once very expensive but are coming down in price. They simplifly the low voltage wiring considerably.

6) Once you're ready, you should be able to get solar for about 25 cents a watt. That is the number you care about. "Cheap" panels on Amazon, Ebay etc are often much more expensive than this.

7) Use breakers and fuses on every power run that can conceivably be shorted. Remember that fusing protects the wiring, not the devices, so size your fuses for the wire gauge you are running. The classic mistake is a 4/0 wire run from a battery to an inverter, with an 18 gauge wire connected directly to the battery for a small DC load without a fuse.

8) If you are a newcomer to electricity, find a friend who's an electrician/electrical engineer and have him help you the first few times. The rules are simple but it's critical you understand them for your own safety.

9) Again DON'T BUY ANYTHING YET! Even if you see a really good deal. Get a plan on paper that makes sense with your loads, your solar availability and your budget, THEN start.

 

[RV8R]

X 2 on @billvon

Don’t Buy Anything until you sort out your needs / design.

AGMs have their place , but what are your reasons for wanting AGMs ?





I have AGMs in my Van & do not worry about cold weather charging “Canada”.

LFP have many advantages over AGMs & at this point if I were to build a new van, I most likely would go LFP ,,, I don’t live in a very cold part of Canada, nor does our use have us up on a ski hill in winter with the heat off.

So use type matters when designing.


If looking @ Victron MPPT ,,, many are good for 12v 24v and even 36v 48v

My Victron 100 | 50 does 12v & 24v ,,, but the real magic is on 24v it doubles the max power of the array can be

12v = 700W
24v = 1400W


Where practical, I try to buy bigger than I “currently” need in all battery chemistries & that are as user programmable as possible. I also buy for expandability. I recently build a portable solar charger box with short #6 wires attached to the MPPT, not that I need #6, but because that is the largest wire the solar charger will take.

Until these tips are common knowledge for you;

Do Not Buy Anything !!
BTW, lots of relevant info for you on my Portable Solar Charger box thread;


Thread 'Portable Solar Charger'
https://diysolarforum.com/threads/portable-solar-charger.79393/

 

[Luismclaughlin]

Hi @Luismclaughlin

I notice only 1 12vdc load ,,, that is a direction towards design for a 120vdc fridge in my mind


View attachment 199986


If, you are looking at an inverter always on system ( or standby ), my gut feeling without knowing anything about your needs or future needs would point my towards;

24vdc batteries
24vdc to 120vac Inverter
Expandability when needed


I would need to know more about what you are trying to achieve (eg are you also heating with propane ?).

You are running an inverter for pretty light loads. I run 12vdc for almost everything other than heat & then I have propane.

IMO, the 12vdc / 120vac might be able to be simplified ?

I am using a wood stove and a wall mount propane heater for heating the house. Also using propane for fridge, stove and 2 piped in propane lights ( with mantels)

I plan on using up to 4 grow lights which consume 42 watts. They would be one 8-10 hours a day.

I didn’t include this before, but realized, I may need this;
At least 1 heat matt 17watts runs 24/7



Washer will probably be a gas powered washer

 

[Luismclaughlin]

X 2 on @billvon

Don’t Buy Anything until you sort out your needs / design.

AGMs have their place , but what are your reasons for wanting AGMs ?


View attachment 199989


I have AGMs in my Van & do not worry about cold weather charging “Canada”.

LFP have many advantages over AGMs & at this point if I were to build a new van, I most likely would go LFP ,,, I don’t live in a very cold part of Canada, nor does our use have us up on a ski hill in winter with the heat off.

So use type matters when designing.


If looking @ Victron MPPT ,,, many are good for 12v 24v and even 36v 48v

My Victron 100 | 50 does 12v & 24v ,,, but the real magic is on 24v it doubles the max power of the array can be

12v = 700W
24v = 1400W


Where practical, I try to buy bigger than I “currently” need in all battery chemistries & that are as user programmable as possible. I also buy for expandability. I recently build a portable solar charger box with short #6 wires attached to the MPPT, not that I need #6, but because that is the largest wire the solar charger will take.

Until these tips are common knowledge for you;

Do Not Buy Anything !!
BTW, lots of relevant info for you on my Portable Solar Charger box thread;


Thread 'Portable Solar Charger'
https://diysolarforum.com/threads/portable-solar-charger.79393/

I have decided to not use agm. But go with Some type of Lithium batteties

 

[Luismclaughlin]

OK here's my list.

1) DON'T BUY ANYTHING YET! Wait until you know your loads and what your goals are.

2) If you want to go small (learning system, more playing around than generating power) go 12V. Stuff is cheap and it's compatible with cars/RVs. If you want to generate a lot of power (i.e. upwards of 3000W) start at 48V.

3) Reduce energy use FIRST. As a rule of thumb, every $1 you spend on efficiency reduces your solar system cost by $5.

4) It's possible - but more difficult - to design a system that you can expand later. Batteries you can expand if you are careful. Solar you can expand. Inverters are harder, since small inverters tend to not stack well. Charge controllers are also difficult, but you can add them incrementally. You'll often have to replace the wiring and protection, and that's not that cheap since copper is expensive.

5) All-in-one systems (inverter + charge controller) are a great way to get started. They were once very expensive but are coming down in price. They simplifly the low voltage wiring considerably.

6) Once you're ready, you should be able to get solar for about 25 cents a watt. That is the number you care about. "Cheap" panels on Amazon, Ebay etc are often much more expensive than this.

7) Use breakers and fuses on every power run that can conceivably be shorted. Remember that fusing protects the wiring, not the devices, so size your fuses for the wire gauge you are running. The classic mistake is a 4/0 wire run from a battery to an inverter, with an 18 gauge wire connected directly to the battery for a small DC load without a fuse.

8) If you are a newcomer to electricity, find a friend who's an electrician/electrical engineer and have him help you the first few times. The rules are simple but it's critical you understand them for your own safety.

9) Again DON'T BUY ANYTHING YET! Even if you see a really good deal. Get a plan on paper that makes sense with your loads, your solar availability and your budget, THEN start.

Thank you