Specd has done his homework I can see. Lots of great information..
I don't suggest putting lots of money into a "first time" battery bank. There is a learning curve to understand how things work. Over discharging a battery will shorten the life dramatically if done repeatedly..
My "training wheel" battery was 4-6 volt golf cart batteries, connected in series/parallel for 12 v.d.c. I destroyed them in 3 yrs. I simply didn't understand the importance of keeping them above 12 volts..
I replaced them with 4 of the same and got 8 yrs. of service from them. Then I went with the big league batteries.. (10 yrs so far)
Exide makes good 6 volt golf cart battery. Here is an example..
Exide Golf Cart Battery 6volt GC115G by Exide Technologies for $79.99 in Price Busters : Rural King
Not real expensive, easy to find, and easy to replace. Those big boy batteries weigh ~110 pounds each..
My battery is near the foot of my bed in the open. I keep an eye on them visually and closely monitor them with a TriMetric 2020..
TriMetric Model Descriptions, Present and Past - Bogart Engineering
I treat my battery as a family member. I make sure they have plenty to drink and if I'm cold, they are too..
I don't suggest putting lots of money into a "first time" battery bank. There is a learning curve to understand how things work. Over discharging a battery will shorten the life dramatically if done repeatedly..
My "training wheel" battery was 4-6 volt golf cart batteries, connected in series/parallel for 12 v.d.c. I destroyed them in 3 yrs. I simply didn't understand the importance of keeping them above 12 volts..
I replaced them with 4 of the same and got 8 yrs. of service from them. Then I went with the big league batteries.. (10 yrs so far)
Exide makes good 6 volt golf cart battery. Here is an example..
Exide Golf Cart Battery 6volt GC115G by Exide Technologies for $79.99 in Price Busters : Rural King
Not real expensive, easy to find, and easy to replace. Those big boy batteries weigh ~110 pounds each..
My battery is near the foot of my bed in the open. I keep an eye on them visually and closely monitor them with a TriMetric 2020..
TriMetric Model Descriptions, Present and Past - Bogart Engineering
I treat my battery as a family member. I make sure they have plenty to drink and if I'm cold, they are too..
The Walmart deep cycle battery made by Johnson Controls is HERE. However, I noticed that it is now advertised with a Marine Cranking Amps (MCA) rating. That means the company has probably changed the product and is now using thinner plates, so that battery can be used/sold as a dual purpose battery. Didn't use to be that way... So those can be scratched off the list.
The 6 volt golf cart batteries are the type you need as OffGridKindaGuy has suggested. Buy as many as you can afford to buy and treat them like a family member as suggested as well. An ex-girlfriend once accused me of caring for my batteries and my tools more than I cared for her.... I couldn't disprove that statement right away so down the road she soon went.
My batteries and tools are hanging in there and doing great though.
Shop for as much storage capacity (in amp hours) as you can afford and don't abuse the batteries. My personal discharge limit is 20% and if I reach that level I begin to cut back my consumption. At 25% discharge my hands begin to sweat and lots of stuff get shut down. Any lower than that the welder gets fired up for an hour or two to partially recharge the bank. I know it sounds ridiculous to be so strict with batteries designed to be deeply cycled. But you get a limited number of those deep discharge cycles, then the bank is junk. If used properly most good quality batteries outlive their normal lifespans by nearly twice the expected years of service.
For audio systems the power supply solution depends on the equipment you need to run. I have several methods and all are used at my place. For my laptop and a few of my audio devices I use a DC-DC boost converter (a switcher) that has adjustable outputs for voltage and current. The lead plugs into the charger jack on my laptop and is switched on or off by a wall switch. Some of my audio stuff are 110 volt units that I opened up, measured the DC coming from the power supply, and found that 13 volts DC could be directly connected to the circuit board (bypass or remove the AC power supply) to power the unit. The result is a clean DC power supply so audio quality is improved, in some cases significantly. One of my portable units is a Pioneer car audio CD/MP3/Bluetooth head unit with small class D amps inside a homebuilt box. Plugs in everywhere and works great.
Small power tools are converted tools that originally had rechargeable batteries in them. I simply gutted the old rechargeables and soldered heavy gauge power cords on them and plug them in anywhere I'm working. All the little stuff are powered by rechargeable batteries, either Lithium or the older NiMh types. Recharger units are homebuilt for each battery type, but if you prefer you can buy those dirt cheap on fleebay from the chinese. DC boost/buck converters as well... the larger ones seem to work fine for most stuff after replacing bulk capacitors with better quality caps.
EDIT: As I mentioned earlier I have small inverters that I can use for certain stuff like my soldering stations. Also on occasion a friend may drop off something they want fixed, so I may use an inverter to test the device while making repairs. Other than a couple exceptions though, I don't use inverters at my place. They are kept mostly for convenience for testing stuff. Inverters are huge wasters of power. I have a 2000 watt pure sine wave inverter that I have never used at all. There are countless alternatives available to you, so integrate them as budget allows. If you intend to live totally off-grid you'll need a high quality, low RPM generator built to last and economical to fuel for the big stuff you have with electric motors. Large DC motors and PWM control systems aren't cost effective conversions for most of the big appliances.
The 6 volt golf cart batteries are the type you need as OffGridKindaGuy has suggested. Buy as many as you can afford to buy and treat them like a family member as suggested as well. An ex-girlfriend once accused me of caring for my batteries and my tools more than I cared for her.... I couldn't disprove that statement right away so down the road she soon went.
My batteries and tools are hanging in there and doing great though.
Shop for as much storage capacity (in amp hours) as you can afford and don't abuse the batteries. My personal discharge limit is 20% and if I reach that level I begin to cut back my consumption. At 25% discharge my hands begin to sweat and lots of stuff get shut down. Any lower than that the welder gets fired up for an hour or two to partially recharge the bank. I know it sounds ridiculous to be so strict with batteries designed to be deeply cycled. But you get a limited number of those deep discharge cycles, then the bank is junk. If used properly most good quality batteries outlive their normal lifespans by nearly twice the expected years of service.
For audio systems the power supply solution depends on the equipment you need to run. I have several methods and all are used at my place. For my laptop and a few of my audio devices I use a DC-DC boost converter (a switcher) that has adjustable outputs for voltage and current. The lead plugs into the charger jack on my laptop and is switched on or off by a wall switch. Some of my audio stuff are 110 volt units that I opened up, measured the DC coming from the power supply, and found that 13 volts DC could be directly connected to the circuit board (bypass or remove the AC power supply) to power the unit. The result is a clean DC power supply so audio quality is improved, in some cases significantly. One of my portable units is a Pioneer car audio CD/MP3/Bluetooth head unit with small class D amps inside a homebuilt box. Plugs in everywhere and works great.
Small power tools are converted tools that originally had rechargeable batteries in them. I simply gutted the old rechargeables and soldered heavy gauge power cords on them and plug them in anywhere I'm working. All the little stuff are powered by rechargeable batteries, either Lithium or the older NiMh types. Recharger units are homebuilt for each battery type, but if you prefer you can buy those dirt cheap on fleebay from the chinese. DC boost/buck converters as well... the larger ones seem to work fine for most stuff after replacing bulk capacitors with better quality caps.
EDIT: As I mentioned earlier I have small inverters that I can use for certain stuff like my soldering stations. Also on occasion a friend may drop off something they want fixed, so I may use an inverter to test the device while making repairs. Other than a couple exceptions though, I don't use inverters at my place. They are kept mostly for convenience for testing stuff. Inverters are huge wasters of power. I have a 2000 watt pure sine wave inverter that I have never used at all. There are countless alternatives available to you, so integrate them as budget allows. If you intend to live totally off-grid you'll need a high quality, low RPM generator built to last and economical to fuel for the big stuff you have with electric motors. Large DC motors and PWM control systems aren't cost effective conversions for most of the big appliances.
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Me too 400W for years before I sold the place. I had no problem using compact florescents at night on a 1000W truesine inverter LED's were not there in the day and the small hit in efficiency at only 50-100w for the whole house did not seem to matter.
The conversion to 12V on the well pump was just too expensive so I used a cheaper 1500W inverter and 120 to 240 step-up and 1/3HP pump with existing wiring. The 70A draw for 5-10min a few times a day is not too hard to make up and both inverters were hooked up with 0000 welding cable. The neighbors couldn't believe I never needed my generator. In any case the generator can be used for emergency charging during long rainy weeks (never had too) far better than making the noise 4-5 times every day.
EDIT - The inverters are turned off when not in use so I could let the bladder tank go down to 15lb or so and there was an extra storage tank for some gravity feed that only needed filling once a year. And I agree the wind generators are a scam gave mine away after I noticed the need for the 75' tower to overcome the laminar flow issues at my location.
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You can salvage a lot of useful 12 volt stuff from old campers or motorhomes, motor boats and old yachts to use in your house. Water pumps, propane refrigerators, DC refrigerators/freezers like the Dometic unit I have, carbon monoxide/smoke detectors, battery monitors, DC breakers, Onan generators etc., many useful devices can be got for free or dirt cheap.
Yard sales are a great place to snoop for stuff too. Most of my 12 volt power tools were picked up at rummage sales for dirt cheap because their rechargeable batteries had gone bad. Sometimes while scrounging the yard sales I see stuff that I know could be powered directly or easily converted to 12 volts, so I buy that stuff and use it right away or store it for future replacement when stuff wears out.
Be creative with solutions, its fun and rewarding to repurpose old stuff. Not only fun, but older stuff generally means better quality stuff than is sold new today. That sadly, is a fact we all have to live with as consumers. But at home, YOU define your levels of independence from the corporate parasite. Take responsibility for your life and enjoy the experience. Freedom is yours the moment your intent is directed to it.
Yard sales are a great place to snoop for stuff too. Most of my 12 volt power tools were picked up at rummage sales for dirt cheap because their rechargeable batteries had gone bad. Sometimes while scrounging the yard sales I see stuff that I know could be powered directly or easily converted to 12 volts, so I buy that stuff and use it right away or store it for future replacement when stuff wears out.
Be creative with solutions, its fun and rewarding to repurpose old stuff. Not only fun, but older stuff generally means better quality stuff than is sold new today. That sadly, is a fact we all have to live with as consumers. But at home, YOU define your levels of independence from the corporate parasite. Take responsibility for your life and enjoy the experience. Freedom is yours the moment your intent is directed to it.
Right on!!! Living off-grid is EASY! Thanks for adding to the conversation!
I don't have a well. I collect cloud juice from my roof and store ~600 gal. inside. This consumes 1/4 of my living area. (960 sq. ft.) I pressure it up with a 12 volt R.V. pump from my indoor storage. I collect in a 375 gal. mushroom tank and pull it inside with another 12 volt R.V. pump..
I compost all of my bathroom waste. I have a urine diverting fixture (for the setter wife) and a wall mounted urinal for me. (the pointer..)
The setter fixture is basically a bucket in a box with a floor boot mounted on one side with an old 12 volt computer fan blowing the bad air outside constantly 24/7 through a flexible drier vent duct. The solids are covered with fine pine chips after each use and dumped on a compost pile when the bucket gets full, paper and all. I clean out the chicken coop and dump that on there too. Makes for excellent planting material..
The best indoor area lighting I found is cold cathode fluorescents. I can light up 2 rooms with 1/2 amp @ 12 volts direct from my battery. I've been using these for years and never had one fail. Gotta build your own fixture but..
12in Dual White Cold Cathode Kit
I have DSL service with a WIFI modem. The modem operates at 12 volts d.c. When the phone guy came here to install, I pulled the wall wart out of the box, cut the lead from it and wired it to my battery. Works fine.. Last long time! (Phone guy cringed while watching me.. LOL)
Tunes... I have tunes everywhere! I Bluetooth XM in the house and on my porch. Wireless inside and out. Most of my amps are either 12 volt or 5 volt, powered with bank batteries or 12 volt LiPo's..
Projection TV/DVD with a 74" screen. I power the projector with a power supply that I built. I convert 12 volts to 24 volts and regulate down to 19.5 volts. The audio/video head is a unit normally used in a motorhome. HDMI to the projector and the audio to the 3.5mm input from the projector for TV. The audio for the DVD comes direct from the player. (45 watts/ch.x4) AM/FM Weather tuner..
Laptop computer with a dc/dc adaptor, propane fridges, tankless propane water heater, propane cook stove, heat with a wood burner..
*I had to build a separate power supply to operate the motor home head unit. Had a nasty ground loop between the projector and the head unit via the HDMI connection on the house battery. That is now my porch supply..
Gotta love it!
I compost all of my bathroom waste. I have a urine diverting fixture (for the setter wife) and a wall mounted urinal for me. (the pointer..)
The setter fixture is basically a bucket in a box with a floor boot mounted on one side with an old 12 volt computer fan blowing the bad air outside constantly 24/7 through a flexible drier vent duct. The solids are covered with fine pine chips after each use and dumped on a compost pile when the bucket gets full, paper and all. I clean out the chicken coop and dump that on there too. Makes for excellent planting material..
The best indoor area lighting I found is cold cathode fluorescents. I can light up 2 rooms with 1/2 amp @ 12 volts direct from my battery. I've been using these for years and never had one fail. Gotta build your own fixture but..
12in Dual White Cold Cathode Kit
I have DSL service with a WIFI modem. The modem operates at 12 volts d.c. When the phone guy came here to install, I pulled the wall wart out of the box, cut the lead from it and wired it to my battery. Works fine.. Last long time! (Phone guy cringed while watching me.. LOL)
Tunes... I have tunes everywhere! I Bluetooth XM in the house and on my porch. Wireless inside and out. Most of my amps are either 12 volt or 5 volt, powered with bank batteries or 12 volt LiPo's..
Projection TV/DVD with a 74" screen. I power the projector with a power supply that I built. I convert 12 volts to 24 volts and regulate down to 19.5 volts. The audio/video head is a unit normally used in a motorhome. HDMI to the projector and the audio to the 3.5mm input from the projector for TV. The audio for the DVD comes direct from the player. (45 watts/ch.x4) AM/FM Weather tuner..
Laptop computer with a dc/dc adaptor, propane fridges, tankless propane water heater, propane cook stove, heat with a wood burner..
*I had to build a separate power supply to operate the motor home head unit. Had a nasty ground loop between the projector and the head unit via the HDMI connection on the house battery. That is now my porch supply..
Gotta love it!
Very creative solutions OffGridKindaGuy! Like your composting setup. And good to see you build your own power supplies too!
For quick and cheap power supplies that can power most anything that comes along, including inkjet/laser printers, I have a few of THESE cheap constant current, constant voltage boost converters stocked up. I stocked up on similar CC/CV buck converters too, for anything requiring less than 12 volts. Search fleebay for DC-DC converter. Loads of stuff there including USB charger/supplies and lithium charger boards. Most of that stuff works fine as is, but if you need clean power for audio its easy to change caps out to better ones, those usually clean them up pretty good, Always buy larger capacity rated stuff you need when buying chinese converters, cause most are way over rated.
You can get temp control/thermostat/fan controllers relay switches on fleebay cheap too. I used to build my own, but now whenever I need another I go to my spare parts bins and pick one out.
The cheap Sanwu TPA3118D2 class D mono amps on fleebay work great and sound great too. Get a few and use one board for each channel for low power, high output audio. There are threads in the Class D forum here for modding them.
Here is a smokin' deal on mono-crystalline panels, two 158 watt panels for $268.00. Shipping is probably $100 per pair but even with shipping its a great deal. Monos are the best. Four of those ($730 or so?) gets you up and running nicely with 632 watts of power and when combined with a Xantrex/Schneider C-40 controller its installitandforgetabotit reliable. Add DC breakers, welding cable runs, voltage/amps meter for monitoring, an 8-pack of golf cart batteries and you got me beat!!
Snoop around and get the best price for the good stuff. You only have to buy most stuff once if you don't scrimp.
For quick and cheap power supplies that can power most anything that comes along, including inkjet/laser printers, I have a few of THESE cheap constant current, constant voltage boost converters stocked up. I stocked up on similar CC/CV buck converters too, for anything requiring less than 12 volts. Search fleebay for DC-DC converter. Loads of stuff there including USB charger/supplies and lithium charger boards. Most of that stuff works fine as is, but if you need clean power for audio its easy to change caps out to better ones, those usually clean them up pretty good, Always buy larger capacity rated stuff you need when buying chinese converters, cause most are way over rated.
You can get temp control/thermostat/fan controllers relay switches on fleebay cheap too. I used to build my own, but now whenever I need another I go to my spare parts bins and pick one out.
The cheap Sanwu TPA3118D2 class D mono amps on fleebay work great and sound great too. Get a few and use one board for each channel for low power, high output audio. There are threads in the Class D forum here for modding them.
Here is a smokin' deal on mono-crystalline panels, two 158 watt panels for $268.00. Shipping is probably $100 per pair but even with shipping its a great deal. Monos are the best. Four of those ($730 or so?) gets you up and running nicely with 632 watts of power and when combined with a Xantrex/Schneider C-40 controller its installitandforgetabotit reliable. Add DC breakers, welding cable runs, voltage/amps meter for monitoring, an 8-pack of golf cart batteries and you got me beat!!
Snoop around and get the best price for the good stuff. You only have to buy most stuff once if you don't scrimp.
That battery monitor looks pretty useful. Maybe I oughta' get me one of those... thanks for the link!
Power needed in time bands
Let's start by getting the requirements by time bands. The blender and microwave will not be run continously.
What will be the effects of inverter power on the Microwave, blender and fan motor? I have had humming and other strange effects running a fan off a computer UPS.
0400 to 0500
Fan 1 x 100 W
Lights 2 x 5 W
0500 to 0600
TV 1 x 80W
Lights 2 x 5W
0600 to 1200
Fan 4 x 100 W
TV 1 x 80W
Blender 1 x 550W
Microwave
1200 to 1500
Fan 4 x 100 W
TV 1 x 80W
Blender 1 x 550W
Microwave 1000W
1500 to 1800
1200 to 1500
Fan 4 x 100 W
TV 1 x 80W
Blender 1 x 550W
Microwave 1000W
1800 to 2100
1200 to 1500
Fan 4 x 100 W
TV 1 x 80W
Blender 1 x 550W
Microwave 1000W
2100 to 2200
1200 to 1500
Fan 4 x 100 W
TV 1 x 80W
Blender 1 x 550W
Microwave 1000W
2200 to 0500
1200 to 1500
Fan 4 x 100 W
Lights 8 x 5W
I need a max of 3 hours power: so this means I have to run my peak loads for 3 hours exept the blender (20 minutes total ) and the fans and lights.
550 x 20/60 + 400 W x 3 hours + 8 Watts x 8 x 3 hours = approx 1575 WH
Let's start by getting the requirements by time bands. The blender and microwave will not be run continously.
What will be the effects of inverter power on the Microwave, blender and fan motor? I have had humming and other strange effects running a fan off a computer UPS.
0400 to 0500
Fan 1 x 100 W
Lights 2 x 5 W
0500 to 0600
TV 1 x 80W
Lights 2 x 5W
0600 to 1200
Fan 4 x 100 W
TV 1 x 80W
Blender 1 x 550W
Microwave
1200 to 1500
Fan 4 x 100 W
TV 1 x 80W
Blender 1 x 550W
Microwave 1000W
1500 to 1800
1200 to 1500
Fan 4 x 100 W
TV 1 x 80W
Blender 1 x 550W
Microwave 1000W
1800 to 2100
1200 to 1500
Fan 4 x 100 W
TV 1 x 80W
Blender 1 x 550W
Microwave 1000W
2100 to 2200
1200 to 1500
Fan 4 x 100 W
TV 1 x 80W
Blender 1 x 550W
Microwave 1000W
2200 to 0500
1200 to 1500
Fan 4 x 100 W
Lights 8 x 5W
I need a max of 3 hours power: so this means I have to run my peak loads for 3 hours exept the blender (20 minutes total ) and the fans and lights.
550 x 20/60 + 400 W x 3 hours + 8 Watts x 8 x 3 hours = approx 1575 WH
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A lot of the cheap UPS systems and cheap inverers uses modified sinewave, to be able to use cheaper components. This will give a lot of higher order harmonics in the power supplies of attached equipment, and not everything will be happy with this power quality. Motors will normally be fine.
I had an el cheapo inverter, but when the doctors gave me a cpap machine to fix my apnea, I didn't dare use the modified sine wave inverter any more, and got a proper inverter. The health care system paid for the first one, but if I break it, I'll have to pay for a new one, myself...
That said - I'd go for a system with DC for most of the low level and/or constant consumption, like lighting, stereo, tv etc, then use an inverter for the intermediate stuff and a generator for heavy use. This requires both dc and ac wiring, though... As the cabin we have is small, I have three 10 amp circuits for the living room, kitchen and out buildings. All these are only low level consumers, eating 3-4 amps at most (the stereo). The inverter is connected directly to the battery bank, on a separate fuse.
That said, if I were doing a new system today, I'd go for a Victron combined charger/inverter. It uses only 5-10w of power, for a unit giving up to 1600W mains power. As soon as you fire up the generator, you can draw more. The charger on these run from 50A and up, so you get a heavier load on your generator. Generators don't like to run at near idle for long periods. The Victron can also keep the battery charged on mains power and provide house power. With a little extra components, you can add automatic start for the generator.
My situation is a bit different - as we have a cabin that sees only occational use, the usage patterns are different, and we have two-three months out of the year where solar charging is negligible.
Johan-Kr
I had an el cheapo inverter, but when the doctors gave me a cpap machine to fix my apnea, I didn't dare use the modified sine wave inverter any more, and got a proper inverter. The health care system paid for the first one, but if I break it, I'll have to pay for a new one, myself...
That said - I'd go for a system with DC for most of the low level and/or constant consumption, like lighting, stereo, tv etc, then use an inverter for the intermediate stuff and a generator for heavy use. This requires both dc and ac wiring, though... As the cabin we have is small, I have three 10 amp circuits for the living room, kitchen and out buildings. All these are only low level consumers, eating 3-4 amps at most (the stereo). The inverter is connected directly to the battery bank, on a separate fuse.
That said, if I were doing a new system today, I'd go for a Victron combined charger/inverter. It uses only 5-10w of power, for a unit giving up to 1600W mains power. As soon as you fire up the generator, you can draw more. The charger on these run from 50A and up, so you get a heavier load on your generator. Generators don't like to run at near idle for long periods. The Victron can also keep the battery charged on mains power and provide house power. With a little extra components, you can add automatic start for the generator.
My situation is a bit different - as we have a cabin that sees only occational use, the usage patterns are different, and we have two-three months out of the year where solar charging is negligible.
Johan-Kr
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Same here my wife too. We used a Prosine pure sine wave inverter for all electronics and Xantrex for well pump. I also used an 8 pack of Trojan T-105's (900AH).
If the figure 1600 refers to the Victron in my post, that's 1600W, not Ah. That inverter has 500Ah battery as a reccomended minimum. Anyways - if you're planning on heavier loads than lights, a water pump and a piddlin' stereo, you'll probably want more juice on tap than 500Ah. Even with deep cycle batteries, pulling them regularly much lower than 40-50% will shorten the life seriously.
We have a 245Ah AGM battery right now, which is a bit small for use in january and february. I'm thinking two 600Ah Rolls 6V batteries might be good when it's time to swap. A new regulator and a couple of 140-160W panels is on the list first...
Johan-Kr
@ BasicHiFi1
The only issue I see with your planned usage is the 4x100 watt fans running a lot. I assume those are AC powered fans? If so, you have 400 watts of AC consumption over many continuous hours (some of those hours in the dark) which means you gotta power those through a big inverter (big enough to handle fans, blender, microwave and TV at once?). Add 15% nominal conversion losses through the inverter and you are in heavy consumption territory.
I would work on eliminating as many loads as possible from the inverter. Buy 12 volt fans. Buy an RV 12 volt TV or convert your existing TV to use DC. In a nutshell... if a device can be run using DC power then do it, that means finding DC powered alternatives or you converting them yourself. Get rid of all voltage conversions as is possible. Your success with a small system is dependent upon this.
If you insist on using an inverter for everything then I recommend a larger system capacity with a MUCH larger capacity battery bank. The reason is obvious... plus, no matter what you have planned for loading now, you are certainly going to be adding more loads to the system as time goes on... because you can!
Its cheaper usually to lower your consumption by eliminating unnecessary inverter conversions than it is to buy and maintain a larger capacity system. Plus its good practice for you to be solving your own problems creatvely, rather than relying on your thick wallet and spending opportunities. Think about your budget... if you can afford a large enough capacity system then you can waste as much of it as you wish.
One more tip.... and this is my personal opinion resulting from decades of bad experiences learning the same lesson over and over again. I've been burned a gazillion times by multi-functional electronic devices. No way... NO ****'n WAY, am I EVER going to combine my charge controller with an inverter or other functional device in my system! What in sam **** are you going to do when your charge controller is smoked? Smoked because of your foolish integration decision of your charge controller with another less important, less critical function in your system? Expect no mercy!
The only issue I see with your planned usage is the 4x100 watt fans running a lot. I assume those are AC powered fans? If so, you have 400 watts of AC consumption over many continuous hours (some of those hours in the dark) which means you gotta power those through a big inverter (big enough to handle fans, blender, microwave and TV at once?). Add 15% nominal conversion losses through the inverter and you are in heavy consumption territory.
I would work on eliminating as many loads as possible from the inverter. Buy 12 volt fans. Buy an RV 12 volt TV or convert your existing TV to use DC. In a nutshell... if a device can be run using DC power then do it, that means finding DC powered alternatives or you converting them yourself. Get rid of all voltage conversions as is possible. Your success with a small system is dependent upon this.
If you insist on using an inverter for everything then I recommend a larger system capacity with a MUCH larger capacity battery bank. The reason is obvious... plus, no matter what you have planned for loading now, you are certainly going to be adding more loads to the system as time goes on... because you can!
Its cheaper usually to lower your consumption by eliminating unnecessary inverter conversions than it is to buy and maintain a larger capacity system. Plus its good practice for you to be solving your own problems creatvely, rather than relying on your thick wallet and spending opportunities. Think about your budget... if you can afford a large enough capacity system then you can waste as much of it as you wish.
One more tip.... and this is my personal opinion resulting from decades of bad experiences learning the same lesson over and over again. I've been burned a gazillion times by multi-functional electronic devices. No way... NO ****'n WAY, am I EVER going to combine my charge controller with an inverter or other functional device in my system! What in sam **** are you going to do when your charge controller is smoked? Smoked because of your foolish integration decision of your charge controller with another less important, less critical function in your system? Expect no mercy!
Question for you: Why do you need four large 100 watt fans? You don't have to explain your reasoning to me. Explain it to yourself. Justify 4 large fan loads to yourself. Think it through, its your most powerful tool and costs nothing.
Then think some more about how you can either eliminate fans, combine single fan load to multiple locations/purposes , and/or provide ventilation from another more creative source?
EDIT: You may have noticed by now that I keep preaching about thinking your way through for creative and/or alternative solutions in your life. Its difficult at first for many... because of all the rotten programming us humans receive from our dysfunctionally designed and implemented hierarchical socio/economic/ruling system. In short, you're gonna be easy prey your entire life for the parasitic powers that be, through their corporations and their govs that apply those excessive forces for your parasitic participation in compliance. IF you aren't willing to be responsible for your own life and all that you experience 1000%.
I must remind myself to THINK. Constantly.
Then think some more about how you can either eliminate fans, combine single fan load to multiple locations/purposes , and/or provide ventilation from another more creative source?
EDIT: You may have noticed by now that I keep preaching about thinking your way through for creative and/or alternative solutions in your life. Its difficult at first for many... because of all the rotten programming us humans receive from our dysfunctionally designed and implemented hierarchical socio/economic/ruling system. In short, you're gonna be easy prey your entire life for the parasitic powers that be, through their corporations and their govs that apply those excessive forces for your parasitic participation in compliance. IF you aren't willing to be responsible for your own life and all that you experience 1000%.
I must remind myself to THINK. Constantly.
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You need to take a fresh look at your consumption figures - the estimates are way off (too high).
First off - the most interesting figure is not wattage. Thats only useful for telling you the maximum consumption. The figure is Wh, converted to Ah drawn from the battery.
There are two figures you need to know for current draw - peak draw and average draw over time. The peak current is important when using an inverter, because you don't want to trigger its protection circuits or blow up component. When figuring out the needed capacity, you need to consider the average current and the duty cycle.
From 0600 to 1200, you list a 550W blender and a 1000W microwave. Nobody runs that equipment for 6 hours straight. I know some people cook steak in the microwave, but it's not going full tilt for all this time.
If you run the blender for maybe 15 minutes, and the microwave for up ta an hour (pr day), that converts to 11Ah for the blender and 83Ah for the Microwave, included 15% loss.
5W for a lamp is a bit too much. When running leds, 1-2W are common sizes. 5W is about a 60W normal bulb... We have a 4W led bar in the kitchen at the cabin. It's usually run at only 1/2 power - that's plenty light.
When you calculate all the amphours through 24 hours, multiply by two, and that's the battery size you need.
Oh - and an inverter makes sense for heavier loads, because you can use longer runs of much thinner gauge cable, and loose less power through wire loss. A 1200W unit eats 100A of current at 12V, but only 5A at 240v.
For cooking, the most effective system use gas bottles.
Johan-Kr
First off - the most interesting figure is not wattage. Thats only useful for telling you the maximum consumption. The figure is Wh, converted to Ah drawn from the battery.
There are two figures you need to know for current draw - peak draw and average draw over time. The peak current is important when using an inverter, because you don't want to trigger its protection circuits or blow up component. When figuring out the needed capacity, you need to consider the average current and the duty cycle.
From 0600 to 1200, you list a 550W blender and a 1000W microwave. Nobody runs that equipment for 6 hours straight. I know some people cook steak in the microwave, but it's not going full tilt for all this time.
If you run the blender for maybe 15 minutes, and the microwave for up ta an hour (pr day), that converts to 11Ah for the blender and 83Ah for the Microwave, included 15% loss.
5W for a lamp is a bit too much. When running leds, 1-2W are common sizes. 5W is about a 60W normal bulb... We have a 4W led bar in the kitchen at the cabin. It's usually run at only 1/2 power - that's plenty light.
When you calculate all the amphours through 24 hours, multiply by two, and that's the battery size you need.
Oh - and an inverter makes sense for heavier loads, because you can use longer runs of much thinner gauge cable, and loose less power through wire loss. A 1200W unit eats 100A of current at 12V, but only 5A at 240v.
For cooking, the most effective system use gas bottles.
Johan-Kr
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Yes on both, case in point if your well is deep it really costs too much to go 12V I got quoted $3000-4000 for a Danfloss SS unit and 200' of heavy duty cable. Cost me $1000 to connect to the existing wires with a Xantrex inverter and transformer, as I said I switched it manually only when needed.
O2Cool fans move a lot of air using ~300mA @ 12 volts. You can buy a bunch of these for the price of an inverter. I've been using these for years. Whack the cord from the wall wart and connect to your 12 volt battery. Just make sure the polarity is correct..
O2Cool 10" Battery-Operated Fin Fan with AC Adapter - Walmart.com
I posted earlier about the almost perfect indoor lighting alternative. (Cold Cathode Florescent) Cheap, very effective, and no inverter involved..
2 fridges. One with a freezer. Propane.. No inverter involved. The light in my larger unit operates at 6 volts. LM7806 and a heat sink fixed that..
My cook stove has electronic ignition. (Propane) It has a holder for 8-"AA" cells. That's 12 volts. Of course it's connected to my house battery..
I have a wire buss from one end of my living area to the other along the ceiling.. (2 Ga. welding cable.. Red/Black) It connects to my house battery through a 30 amp blade fuse. I have never blown that fuse in 20 yrs. My whole house runs through it, including my 400 watt inverter. (The only one that I own) I use it to charge my cordless hand tools and my soldering iron..
I tap into the buss and run to cigar lighter outlets where I want power using 12 Ga. stranded. I never pull more than 4 amps from any outlet. If something requires more current, I connect directly to the buss.. (All connections to the buss are fused on the positive wire at the buss)
All these years, I convinced myself that A.C. voltage is a bad word and I refuse to make or use it unless it can't be avoided. I just got lazy with the hand tool chargers and I like my A.C. soldering iron better than my 12 volt or butane units..
I don't need or use a microwave. (Much) I have one and I can use it with my generator, which is used for a back up during cloudy winter periods. I have an A.C. toaster and if I decide I want a treat, I'll fire up the generator and fry me up some dippy eggs..
Well pumps don't need as much power at free flow as they do to create pressure. If you have storage at ground level and free flow the well pump to fill a tank, you use much less power. It's simple to pressure it up after that with 12 volts..
I designed a system for a friend. We buried a 2000 Gal. tank just above his floor level on a slight bank behind his house. This being the water would flow from the tank via gravity to the house. (Not intended to create any pressure, just flow) Put an over flow line on the tank for an indicator of when it was full. (He can see it from a window) Wired a big Honda 220 volt remote start/shut down generator to the pump with a switch inside the house to control the pump. He fires up the generator, kicks the pump in, and watches the over flow. Water comes out the over flow, he shuts down the pump and then the generator. It takes ~3/4 gal. of gasoline to fill his tank and the tank lasts him and his wife for weeks..
Inside, a simple 12 volt RV pump is used with a small pressure tank. Work fine.. Last long time!!
O2Cool 10" Battery-Operated Fin Fan with AC Adapter - Walmart.com
I posted earlier about the almost perfect indoor lighting alternative. (Cold Cathode Florescent) Cheap, very effective, and no inverter involved..
2 fridges. One with a freezer. Propane.. No inverter involved. The light in my larger unit operates at 6 volts. LM7806 and a heat sink fixed that..
My cook stove has electronic ignition. (Propane) It has a holder for 8-"AA" cells. That's 12 volts. Of course it's connected to my house battery..
I have a wire buss from one end of my living area to the other along the ceiling.. (2 Ga. welding cable.. Red/Black) It connects to my house battery through a 30 amp blade fuse. I have never blown that fuse in 20 yrs. My whole house runs through it, including my 400 watt inverter. (The only one that I own) I use it to charge my cordless hand tools and my soldering iron..
I tap into the buss and run to cigar lighter outlets where I want power using 12 Ga. stranded. I never pull more than 4 amps from any outlet. If something requires more current, I connect directly to the buss.. (All connections to the buss are fused on the positive wire at the buss)
All these years, I convinced myself that A.C. voltage is a bad word and I refuse to make or use it unless it can't be avoided. I just got lazy with the hand tool chargers and I like my A.C. soldering iron better than my 12 volt or butane units..
I don't need or use a microwave. (Much) I have one and I can use it with my generator, which is used for a back up during cloudy winter periods. I have an A.C. toaster and if I decide I want a treat, I'll fire up the generator and fry me up some dippy eggs..
Well pumps don't need as much power at free flow as they do to create pressure. If you have storage at ground level and free flow the well pump to fill a tank, you use much less power. It's simple to pressure it up after that with 12 volts..
I designed a system for a friend. We buried a 2000 Gal. tank just above his floor level on a slight bank behind his house. This being the water would flow from the tank via gravity to the house. (Not intended to create any pressure, just flow) Put an over flow line on the tank for an indicator of when it was full. (He can see it from a window) Wired a big Honda 220 volt remote start/shut down generator to the pump with a switch inside the house to control the pump. He fires up the generator, kicks the pump in, and watches the over flow. Water comes out the over flow, he shuts down the pump and then the generator. It takes ~3/4 gal. of gasoline to fill his tank and the tank lasts him and his wife for weeks..
Inside, a simple 12 volt RV pump is used with a small pressure tank. Work fine.. Last long time!!
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