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Which power inverter to buy? Newbie here!

Vafarmer

New Member
Joined
Jan 9, 2022
Messages
59
Hello to all,
I’m looking to go full solar but, I’m trying to learn all the basics first. Then, move on from there.

I just purchased
-100watt Renogy starter kit.
-2 Exide 24MDC deep cycle battery
-looking to power a barn. In the future. Not powering all this at first but, want to power this stuff when I get more solar panels and batteries.
2- 6 watt bulbs
1 mini fridge(beer)
1 chicken waterer warmer (60 watt)
2 15 watt fans in chicken coop
I’m on a tight budget right now and want to get started on slowly.
What is the most powerful modified sound wave power inverter for under $100 bucks to get me started?
Thanks for any help in this journey to get off the grid!
 
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Yeah, I did think the price was low for the wattage. But, hoping it’ll be good enough to get my feet wet and get started.
 
I ordered a 400watt pure sine wave at first to get started but, 400 watts wouldn’t even get my mini fridge running. That inverter crapped out in 2 days
 
You are already setting yourself up for failure. I can immediately tell you that what you are putting together is totally inadequate, and it's wasted money.

First, your batteries are ~65Ah each? That means 130Ah total. What's optimal for charging is (130Ah/8) X 13V charging X 1.175fudgefactor = 248W. So, a 250W panel instead of one 100W panel.

In the middle of summer, you are not likely to get more then 5 sunhours per day, so 100W X 5 sunhours = 500Wh of power total. Most inverters in the price range you are looking at consume about 2A of power, so just leaving the inverted turned on with no load consumes 2A X 12V X 24hr = 576Wh of power. Add things like a frig on top of that, and you will never keep your batteries charged. They will die a quick death from sulfination. In winter, it might not last three days.

A modified sine-wave inverter is most likely going to damage the motor on the mini-frig.

So, after all the money you've already put in, you'll need to spend more to buy more panels, buy a better inverter, and buy a replacement refrigerator.
 
Hello to all,
I’m looking to go full solar but, I’m trying to learn all the basics first. Then, move on from there.

I just purchased
-100watt Renogy starter kit.
-2 Exide 24MDP deep cycle Marine battery
-looking to power a barn. In the future. Not powering all this at first but, want to power this stuff when I get more solar panels and batteries.
2- 6 watt bulbs
1 mini fridge(beer)
1 chicken waterer warmer (60 watt)
2 15 watt fans in chicken coop
I’m on a tight budget right now and want to get started on slowly.
What is the most powerful modified sound wave power inverter for under $100 bucks to get me started?
Thanks for any help in this journey to get off the grid!
I'm really a solar-power beginner, though I've tinkered with it off-and-on for years. Definitely take what I have to say with a grain of salt! (y)

I see that you understand that you will need more energy production to power the heavier loads that you have listed. I don't have a lot of knowledge regarding inverters but I did want to maybe emphasize your actual question...which is "What is the most powerful modified sound sine wave power inverter for under $100 bucks to get me started?". Now having re-stated that...

The ratio of pv panel to battery storage is kind of reversed in my mind. I think I would invest, to begin with, in more pv panel power (three more would be great!). As it is, you can't use but probably a little over 20 amp hours on good sunny days being as your panel can only produce that much power and there are inherent system-losses. Your battery bank is capable of being discharged down to 50% state-of-charge, which would be 65aH of power usage (half of 130aH) without over-discharging it. But, your single pv panel cannot restore that much power to the battery bank. You have the capacity to store 65 amp hours daily but only capability of refilling only 20 amp hours each day. If you use more power than the pv panel can provide then in a few days you find your battery bank over-discharged and maybe even dead...not good for the batteries.

Do you already have a solar charge controller? Amp capacity (30amp would be great!)? PWM or MPPT? A PWM controller is around 70% efficient while a MPPT will be around 90-95% efficient. This matters more for multiple panel setups...but, to future proof things the MPPT would be best. If you don't have a charge controller yet I would say add the inverter funds to the charge controller funds and go with an MPPT. If you've already bought a PWM then continue on with what you have, maybe later upgrading to an MPPT. ?

Inverters will be around 80% efficient...so roughly, to power a 100w a/c item you need 120w going into the inverter. And, as long as the inverter is powered on it will draw power from the battery bank whether a load is being powered or not. A cooler with two or three 2-liter drink bottles

Both heating and cooling are power-suckers.

I would optimize my solar setup's ability to refill the maximum power the battery bank can provide before I ventured on to other things.

Here are some *very, very* rough load calculations that I made (and I probably have errors in them, but I think they're close):
*2 amp hours - two 6w bulbs - 4 hours each, per day
**53 amp hours - two 15w fans for chicken coop - 24-hours a day (running only one will get you close to your daily production limit)
**67 amp hours - 60w waterer warmer - 12 hours per day (trimming the time to maybe 8 hours might work in regards to power, but freezing?)
***35 amp hours - rough guesstimate for 8 hours of mini-fridge cycling per day
Notes:
*To save a couple of amp hours you could cut this down to one bulb
**The fan and water heater will not be running at the same time, so that's a plus.
***The min-fridge should self-cycle on/off...running roughly 1/3 of the time...in the winter probably less...in really hot weather, possibly more.
Also, any a/c item running through the inverter will involve the 20% rough overhead of power requirement.

These are just some thoughts from somebody who knows just enough to be dangerous...seriously. I hope somebody comes along and corrects me on errors, as this is a learning experience for me and mental(illness) exercise. So take the above with a grain of salt...it's worth exactly what you paid for it! :)
 
I'm really a solar-power beginner, though I've tinkered with it off-and-on for years. Definitely take what I have to say with a grain of salt! (y)

I see that you understand that you will need more energy production to power the heavier loads that you have listed. I don't have a lot of knowledge regarding inverters but I did want to maybe emphasize your actual question...which is "What is the most powerful modified sound sine wave power inverter for under $100 bucks to get me started?". Now having re-stated that...

The ratio of pv panel to battery storage is kind of reversed in my mind. I think I would invest, to begin with, in more pv panel power (three more would be great!). As it is, you can't use but probably a little over 20 amp hours on good sunny days being as your panel can only produce that much power and there are inherent system-losses. Your battery bank is capable of being discharged down to 50% state-of-charge, which would be 65aH of power usage (half of 130aH) without over-discharging it. But, your single pv panel cannot restore that much power to the battery bank. You have the capacity to store 65 amp hours daily but only capability of refilling only 20 amp hours each day. If you use more power than the pv panel can provide then in a few days you find your battery bank over-discharged and maybe even dead...not good for the batteries.

Do you already have a solar charge controller? Amp capacity (30amp would be great!)? PWM or MPPT? A PWM controller is around 70% efficient while a MPPT will be around 90-95% efficient. This matters more for multiple panel setups...but, to future proof things the MPPT would be best. If you don't have a charge controller yet I would say add the inverter funds to the charge controller funds and go with an MPPT. If you've already bought a PWM then continue on with what you have, maybe later upgrading to an MPPT. ?

Inverters will be around 80% efficient...so roughly, to power a 100w a/c item you need 120w going into the inverter. And, as long as the inverter is powered on it will draw power from the battery bank whether a load is being powered or not. A cooler with two or three 2-liter drink bottles

Both heating and cooling are power-suckers.

I would optimize my solar setup's ability to refill the maximum power the battery bank can provide before I ventured on to other things.

Here are some *very, very* rough load calculations that I made (and I probably have errors in them, but I think they're close):
*2 amp hours - two 6w bulbs - 4 hours each, per day
**53 amp hours - two 15w fans for chicken coop - 24-hours a day (running only one will get you close to your daily production limit)
**67 amp hours - 60w waterer warmer - 12 hours per day (trimming the time to maybe 8 hours might work in regards to power, but freezing?)
***35 amp hours - rough guesstimate for 8 hours of mini-fridge cycling per day
Notes:
*To save a couple of amp hours you could cut this down to one bulb
**The fan and water heater will not be running at the same time, so that's a plus.
***The min-fridge should self-cycle on/off...running roughly 1/3 of the time...in the winter probably less...in really hot weather, possibly more.
Also, any a/c item running through the inverter will involve the 20% rough overhead of power requirement.

These are just some thoughts from somebody who knows just enough to be dangerous...seriously. I hope somebody comes along and corrects me on errors, as this is a learning experience for me and mental(illness) exercise. So take the above with a grain of salt...it's worth exactly what you paid for it! :)
I do have a 30 amp PWM charge controller. The batteries were given to me for free along with the everything else I listed. I’m just trying to get started and learn with a small cheap system before I spend money on a nice system. What I have now is just to get my feet wet and learn what I can do with it. I’m not looking to power a fridge yet. Guess it’ll be just
1 bulb 6w
Chicken coop waterer warmer 60w
1 fan 15w
The waterer cycles on and off just to keep the water from freezing.
Bulb only on when we lockup the chickens.
Fan stays on for air circulation.
Thanks for the breakdown of everything. I’m really looking forward to learn as I go with this little system and learn you guys on here.
 
You are already setting yourself up for failure. I can immediately tell you that what you are putting together is totally inadequate, and it's wasted money.

First, your batteries are ~65Ah each? That means 130Ah total. What's optimal for charging is (130Ah/8) X 13V charging X 1.175fudgefactor = 248W. So, a 250W panel instead of one 100W panel.

In the middle of summer, you are not likely to get more then 5 sunhours per day, so 100W X 5 sunhours = 500Wh of power total. Most inverters in the price range you are looking at consume about 2A of power, so just leaving the inverted turned on with no load consumes 2A X 12V X 24hr = 576Wh of power. Add things like a frig on top of that, and you will never keep your batteries charged. They will die a quick death from sulfination. In winter, it might not last three days.

A modified sine-wave inverter is most likely going to damage the motor on the mini-frig.

So, after all the money you've already put in, you'll need to spend more to buy more panels, buy a better inverter, and buy a replacement refrigerator.
Everything was given to me for free. I’m using this stuff to learn before I spend money on a nice system. I was thinking it would be nice to learn what it’s capable of and how everything works as a newbie before spending money. That’s why I’m just looking for a cheap inverter under $100 to get this system working. If anything I’ll be keeping this cheap system and installing in my Toyota Tacoma for off-road/ camping trips once I get a nice solar system. But, I have a lot to learn and practice first.
That’s where this little system and learning people like you guys comes in.
Thanks for all the advice. Looking forward to learn more
 
Everything was given to me for free. I’m using this stuff to learn before I spend money on a nice system. I was thinking it would be nice to learn what it’s capable of and how everything works as a newbie before spending money. That’s why I’m just looking for a cheap inverter under $100 to get this system working.
Forgetting the beer in the chicken coop it looks like you have slightly over a 100a load when the fan, lights and waterer are all running at once.

I'd look at something about 200w rather than the 1000w Krieger to match your needs
Remember: modified sine wave is OK for your chickens but not for electronics and appliances. (fans too to some extent)
Later as you build a better system you will want a pure sine wave inverter

Keeping it in the "forum family" I'll send you to HighTechLab (current connected)
I believe Aims is better quality than the Amazon offerings I saw.
https://www.currentconnected.com/product/aims-msw/
 
I just checked the Aims inverter out and the reviews sound pretty good. Seems a lot of people use them for there reliability. I can get one of those within my budget to. Guessing if I can’t make the power then, I don’t need a 1000watt inverter right?
 
What is the most powerful modified sound wave power inverter for under $100 bucks to get me started?
That is sorta the wrong question.

$100 is less money than $200 but a $100 inverter is way more expensive than a $200 inverter.

This uses ~30W at idle and will start my minifridge no problems.

The next problem you will have is not enough usable batteries. The following problem will be not enough panels.
100watt Renogy starter kit.
This is not enough to use those batteries and recharge at the same time. You might get by if you get lots of sun-days, you may not.

My 200W of panels and two bigger batteries with running a fridge experiment just barely did the deed on sunny days and it didn’t at all on a cloudy day.
 
I do have a 30 amp PWM charge controller. The batteries were given to me for free along with the everything else I listed. I’m just trying to get started and learn with a small cheap system before I spend money on a nice system. What I have now is just to get my feet wet and learn what I can do with it. I’m not looking to power a fridge yet. Guess it’ll be just
1 bulb 6w
Chicken coop waterer warmer 60w
1 fan 15w
The waterer cycles on and off just to keep the water from freezing.
Bulb only on when we lockup the chickens.
Fan stays on for air circulation.
Thanks for the breakdown of everything. I’m really looking forward to learn as I go with this little system and learn you guys on here.
The chicken coop will be the perfect project for getting some solar-education under your belt before investing further. I just set up a small 12-watt(ish) surplus panel and a charge controller to keep a group-27 "marine" battery charged up to power my fence around my vegetable garden. I used a little $20, 20amp waterproof PWM charge controller and roughly 18(?) feet of 12/2UF (uv-resistant) solid wire to connect the solar setup to the battery. I've still got to bury the wire and mount the panel on a fence post but it's working great...I might even add a couple of LED lights to give some illumination if I'm out there late in the evening or at night.

One thing you might want to look into is using a fuse between the battery and the loads. A basic $15 fuse block like this 12V 6-Circuit Fuse Block would make wiring simple and fuse each circuit for you.

Is the chicken waterer 12v or 120v? If it is 120v you might be interested in going to 12v. Here's a DIY plan for one using a metal cookie tin and a common 1157 automotive taillight bulb: 12-Volt Cookie-Tin Chicken Waterer Warmer. If you have access to a junkyard/junk-car somewhere you could possibly recycle a bulb and socket from it...even the wire. Some insulation around the sides of the tin and below it and it'd do a fair job of heating your water...you could choose between the low, high, or both powered filaments...the junk car could also provide the insulation from the bottom of the hood, just be careful handling it as you don't want to end the day itching....yeah, I'm a bit "cheap" on some most things. ?

I'm not sure about the timer aspect for the 12v waterer warmer, though. Here's a link to a 12v timer on Amazon, it has a decent review and is fairly cheap, around $14: JVR 12V Timer Switch Programmable Digital 12 Volt DC/AC/Solar Battery Powered.

I am curious about the use of the fan, though. Do you use it during cold weather, also? I *highly* recommend you check out this PDF of a book, "Open Air Poultry Houses for All Climates by Prince T. Woods, MD". Here is another link to the book that might work better. The book was printed in 1912 and is an excellent book detailing open-air poultry houses...construction, use, etc., back when they didn't have the luxuries of lots of electricity of any kind. You can get a reprint of it from Amazon if you wish. Woods was well respected and many of his ideas were incorporated into the poultry industry. Excellent reading today for small to large backyard flock owners. ?

Once you get the 12-volt part of using solar and your charge/discharge cycles figured out then you will have more mental ammo to use in deciding on an inverter and using it optimally. I really think the chicken coop is a good project to cut your solar teeth on!

Btw, I keep a couple of 2-liter soda bottles of frozen water along with two or three small 12-16oz frozen water bottles in the home freezer for keeping my "drinks" cool when I'm away from the refrigerator. The bottled ice usually lasts 2-3 days if the cooler is kept in the shade...when I get back home I plop the bottles back into the freezer for next time! ;)
 
It’s a 120v heater. Damn, I’m in Backyard chickens forum every once in awhile and I’ve never seen that heater. I’m definitely going that route!!! As far as the fans we use 2 fans during the summer for cross ventilation and to get a nice breeze in the coop. It’s a pretty big coop . About 14x24 ft.. the coop is on the side of the barn where the hay room for the goats is. Also have a tool room in the barn. Fridge is for the tool room and lights are for the barn it’s self.
For now I just want the heater and some lights going.
Thanks for the help. I’m looking into that heater tonight.
 
Ok. So you currently have 120v ac electricity at the coop? Extension cord? How far is it to the power source/outlet?

A 14x24 coop is nice sized. Definitely look at Woods book, especially the first of the book where he lays out some of the why’s and how’s of “open air” coops.
 
Yes, I have 120v going to the barn/ coop right now. Extension cord going to the coop is about 20ft from power source.
The barn is actually the original house on the property from back in the 1940’s. The front deck of the house was converted to the chicken coop.
Closed the deck up with plywood, put 2 windows with fans in them for ventilation during the summer and added a door on the side of the deck for easy access while cleaning and collecting eggs.
The old kitchen is now the tool room and the 1 bedroom is the hay room.
In the future I would love to have the barn completely solar! That’s down the road once I get this solar experiment down packed first.
Do they have low wattage 120v submersible water heaters?
 
You could get some 12/2UF wire that you can bury and have 120v at the coop/barn without having an extension cord laying on the ground. I bought some a couple of months ago to install switches on the security lights at our church and it was $50 for 50 feet of it.

I'll repeat, check the Woods book out. Does the porch/coop per chance face south? The big thing with the Woods style of chicken houses is that there is a wall inside that separates the roosting area from the rest of the coop but has a doorway to allow the chickens (and chicken owner) free passage to either side of the wall. It acts as a baffle against the elements while still allowing fresh air inside and allowing the chickens to venture out into a wire-mesh fenced area for sunshine and more open air. It helps with disease and keeping the coop "fresh". The mental image I have of the coop is one where you could remove one end wall and maybe 3-4 feet of the long wall, run a 2x6 on edge around the opened perimeter install wire-mesh fencing going up from that. Take the removed end wall and use it for the interior baffle. If you look at Woods book you'll see where I'm coming from.

Did you mean 12v volt submersible water heaters? Probably. Again...heating and cooling (other than fans) are energy hogs.
 
You could get some 12/2UF wire that you can bury and have 120v at the coop/barn without having an extension cord laying on the ground. I bought some a couple of months ago to install switches on the security lights at our church and it was $50 for 50 feet of it.

I'll repeat, check the Woods book out. Does the porch/coop per chance face south? The big thing with the Woods style of chicken houses is that there is a wall inside that separates the roosting area from the rest of the coop but has a doorway to allow the chickens (and chicken owner) free passage to either side of the wall. It acts as a baffle against the elements while still allowing fresh air inside and allowing the chickens to venture out into a wire-mesh fenced area for sunshine and more open air. It helps with disease and keeping the coop "fresh". The mental image I have of the coop is one where you could remove one end wall and maybe 3-4 feet of the long wall, run a 2x6 on edge around the opened perimeter install wire-mesh fencing going up from that. Take the removed end wall and use it for the interior baffle. If you look at Woods book you'll see where I'm coming from.

Did you mean 12v volt submersible water heaters? Probably. Again...heating and cooling (other than fans) are energy hogs.
Yes, I D meant a 12v volt submersible water heaters. I just got done reading the Woods book out. Crazy, I’ve always been nervous about the chickens getting to cold during the winter. So, I always put extra thick bedding down. Even put vasoline on there combs so, they won’t get frost bite!
The way I have mine setup is the chickens free range with the goats all day. Then, they get locked up at night in the large coop.
I like the Woods way because of the ventilation and just have a small area for roosting and a lot less cleaning!!!. Right now the roosting area is so big but, we do have 39 chickens.
 
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