Off Grid Experiment Guidance and Feedback Appreciated

[SeanP]

Hi All.

I am in the process of setting up a caravan to move to my land plot in WA. My plans to experiment further with off grid power and put learnings into house as I build it. I just fitting it out caravan to be off grid but also have 240v (via generator/inverter) or plug in side of caravan. A lot of the items are either gas, mains powered or 12V or a combination i.e lights are 12V LEDs and can also be be used on mains power as they have a fluorescent bulb as well. Fridge is 12v, mains and gas. I have a 12V TV, charging points for phones, PC etc all 12V. Details below on equipment I want run on 12V or via a 12v-240 inverter:

1. 3 off 12v LED lights
2. 24" 12v LED TV
3. Charging points for mobile phones, PC etc
4. 12v Sound bar
5. TV Ariel (12v power supply).

Items I want to run on 12V via inverter are:

1. 1000W 240 V kettle. takes about 3 mins to boil I like my coffee so putting down 500W per day usage.
2. 1100W microwave. I haven't used this yet but it will be utilised at some stage.

I have a mixture of gas/mains cooking equipment but will probably run these entirely on gas including hot water system.

For power generation I have configured:

1. 1 x 330 W solar panel
2. 2 x 145AH AGM gel batteries
3. 1 x 30 Amp solar controller.
4. 1 x 2000W constant sine wave inverter 4000W peak.

I also have a 250W solar panel and 165AH AGM gel battery and another 30 amp solar converter. My original plan was to run everything else on the two 145AH batteries but run the firidge independently on the 160AH battery but its a 90L 150W and proved to be too power hungry so its gas unless I can source another more efficient 12V one.

As it stands just now I am running 12V for the items above for 12V lights, phone charging points, TV, sound bar, TV Ariel. I am having trouble seeing how long it takes to charge my batteries and when they are fully charged. I have been taking voltage reading every hour for last week! I have a wireless battery management system set up but I cannot get it configured to see what current I am using/putting in. My read is that I am using about 10% of my power. I want to stay below 30%-40%so not to stress my batteries but also want to run my kettle, microwave periodically via the inverter. Questions I have:

1. I have attached chart of my daily voltage readings. Am I interpreting it correct in my 10% power usage?

2. I don't want to run the kettle/Microwave all the time just when needed. However if I leave my inverter on but not in use will the power drain be manageable keeping me below my 30%-40%daily drain on my batteries, with the above usage and periodic use of microwave/kettle or even 240V fluorescent lights?

3. I have a 160AH AGM gel battery that I haven't hooked up. What would be the knock on effect if Iwire it to my two existing 145AH AGM gel batteries? Or am I better to keep this on a different system with a 250W solar panel and 30 amp solar converter that I have spare? I don't know the effect mixing a 160AH with two145AH would be?

Any suggestions, feedback would be very appreciated, I have been playing with solar these last few years but always had backup of mains power, I don't have that luxury as my plot is out in the sticks with no mains power (I do have a back up generator

 

[SeanP]

Further information, I am surrounded by trees hence the short exposure too the sun while I fit out my caravan before moving into my property which is a sun magnet compared to where it is now.

 

[kernel]

Fun stuff. Nice graphic data.

 

[SeanP]

Fun stuff. Nice graphic data.

Its the engineer in me, need to understand how stuff works so always taught to measure everything so you can understand, fix or modify it.

 

[SeanP]

I

Don't know the full cost of these systems, apparently they have been around for awhile, "pv-direct" systems may complement your battery system.

Not sure how much light you need but at my place we use Dollar Store led night lights--they give sufficient light and only use 0.4 watts. We do still use other lights , 2 watt bulbs--8 watt bulbs ( one can even get .5 [1/2] watt bulbs if they desired) but those dollar store ones are great for "seeing enough" to boogey around the house at night.

I'm covered for lights got some 12V LEDs that fitted into my van as replacement for the old style, I have three of them in the van at 3.6W each so they are pretty efficient, almost as good as the 240v fluorescent that is in.

 

[Frank Pyke]

Hi All.

I am in the process of setting up a caravan to move to my land plot in WA. My plans to experiment further with off grid power and put learnings into house as I build it. I just fitting it out caravan to be off grid but also have 240v (via generator/inverter) or plug in side of caravan. A lot of the items are either gas, mains powered or 12V or a combination i.e lights are 12V LEDs and can also be be used on mains power as they have a fluorescent bulb as well. Fridge is 12v, mains and gas. I have a 12V TV, charging points for phones, PC etc all 12V. Details below on equipment I want run on 12V or via a 12v-240 inverter:

1. 3 off 12v LED lights
2. 24" 12v LED TV
3. Charging points for mobile phones, PC etc
4. 12v Sound bar
5. TV Ariel (12v power supply).

Items I want to run on 12V via inverter are:

1. 1000W 240 V kettle. takes about 3 mins to boil I like my coffee so putting down 500W per day usage.
2. 1100W microwave. I haven't used this yet but it will be utilised at some stage.

I have a mixture of gas/mains cooking equipment but will probably run these entirely on gas including hot water system.

For power generation I have configured:

1. 1 x 330 W solar panel
2. 2 x 145AH AGM gel batteries
3. 1 x 30 Amp solar controller.
4. 1 x 2000W constant sine wave inverter 4000W peak.

I also have a 250W solar panel and 165AH AGM gel battery and another 30 amp solar converter. My original plan was to run everything else on the two 145AH batteries but run the firidge independently on the 160AH battery but its a 90L 150W and proved to be too power hungry so its gas unless I can source another more efficient 12V one.

As it stands just now I am running 12V for the items above for 12V lights, phone charging points, TV, sound bar, TV Ariel. I am having trouble seeing how long it takes to charge my batteries and when they are fully charged. I have been taking voltage reading every hour for last week! I have a wireless battery management system set up but I cannot get it configured to see what current I am using/putting in. My read is that I am using about 10% of my power. I want to stay below 30%-40%so not to stress my batteriesView attachment 6763 but also want to run my kettle, microwave periodically via the inverter. Questions I have:

1. I have attached chart of my daily voltage readings. Am I interpreting it correct in my 10% power usage?View attachment 6761

2. I don't want to run the kettle/Microwave all the time just when needed. However if I leave my inverter on but not in use will the power drain be manageable keeping me below my 30%-40%daily drain on my batteries, with the above usage and periodic use of microwave/kettle or even 240V fluorescent lights?

3. I have a 160AH AGM gel battery that I haven't hooked up. What would be the knock on effect if Iwire it to my two existing 145AH AGM gel batteries? Or am I better to keep this on a different system with a 250W solar panel and 30 amp solar converter that I have spare? I don't know the effect mixing a 160AH with two145AH would be?

Any suggestions, feedback would be very appreciated, I have been playing with solar these last few years but always had backup of mains power, I don't have that luxury as my plot is out in the sticks with no mains power (I do have a back up generator

If you can cook and heat water using bottled gas then I would. Your LED lights, TV etc. draw very little current by comparison.