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I just bought an off-grid cabin that needs an expanded off-grid energy system. Currently the cabin has a buried 500 gal propane tank(at purchase 60% full), 8kw generac guardian(propane), back up 5.5kw gas generator, propane fridge, propane stove, propane fire place, 500ft well(240v submerged), propane on demand hot water(2xD batteries) and central heat and air. Closest grid power is 3 miles down the forest service road. I'm 7 miles off pavement up the service road, truly in the middle of nowhere and I love it. Location is in North Georgia in the Chattahoochee NF.
Reduce:
My first order of business is to reduce my consumption needs. All of the lights/bulbs are getting changed to LED. The countertop microwave is going away.
Worse Case Daily 110v Energy Draw:
10 7-watt LED bulbs @ 12 hours a day: 840 watt hours
3 120-watt ceiling fans 12 hours a day: 360 watt hours
1 100-watt TV 4 hours a day: 400 watt hours
1 50 watt radio 4 hours a day: 200 watt hours
1 87-watt philips respironics 8 hours a day: 696 watt hours
= ~2500 watt hours x 1.5 fudge 3750 watt hours
I'm not sure how to calculate well pump daily usage, it has a 30 gallon pressure tank. Plus other small misc things like charging phones and laptop etc.
I'm installing a security system that is based on 3 bushnell cellular game cameras with Lion batteries and each have solar panels so they don't need to be hooked to the system. This will allow me to have a remote security system that is self powered and will text my phone on movement. Also during hunting season I can easily move the cameras without having to move wires or power around. Shocking that there is good AT&T service on top the mountain but there is. I'll be hanging up solar powered motion lights too.
Planned System:
Magnum 4448 pae
Magnum MMP panel
8x6v AGM batteries 390AH Crown L16(or similar) - 18720 watt hours
(Panels and Charge controller later)
My Plan:
I believe the 4448 inverter is plenty big to run all 110v and well pump in bursts, but obviously not house A/C. I plan to wire it directly to the house panel to supply both 110 and 220v. You may be laughing at this point because I mentioned central A/C above, but just bare with me. Since the magnum has a 60amp, or 2x30amp feed in from the generator to pass through and charge the batteries and supply the house panel with power, my first question is by running the central A/C off generator only will the pass through on the magnum be sufficient? I know the 48v battery bank won't be CLOSE to even starting the central unit so I'll just run it off genset.
If the genset pass through will run the central A/C what problems can I expect? If the genset shuts down while A/C is running and the magnum tries to switch to batteries will the amp draw kill the batteries until the magnum can shut down or just pop a breaker? Is there any protection from this besides installing another house panel and isolating A/C and well pump on genset only?
I mentioned above that I will be adding panels and charge controller later(if possible). Since the magnum has a built in 30amp charger I figure until I install PV and midnight 150 I can just keep the batteries charged with genset. The generac can be started from the house already, and I'll wire in an autostart from the magnum. Does the magnum do a sufficient job knowing when to start the generator and charge, or should I go ahead and install the midnight with whizbang to kick on the genset? Genset is currently set to run once a month for 10 minutes but can be programmed to run weekly to keep batteries topped off while I'm not there. Draw on batteries while I'm not there should only be the magnum itself.
PV Panels
Since I'll be getting about 4 good hours a day I figure 16x300 watt panels will be good? That's 4800 watts x 4 hours = 19200 watt hours to match my battery bank.
I'm pretty much a newb at all this so hopefully my initial thoughts aren't too far off the mark. Later on down the road(5 years or when first battery set needs replaced) I'll look at 24x2v 1150ah batteries and a 48v mini split to replace the central A/C. Or just add another string of 8x6v and another midnight for that run.
Thoughts, concerns?
Moonie
Reduce:
My first order of business is to reduce my consumption needs. All of the lights/bulbs are getting changed to LED. The countertop microwave is going away.
Worse Case Daily 110v Energy Draw:
10 7-watt LED bulbs @ 12 hours a day: 840 watt hours
3 120-watt ceiling fans 12 hours a day: 360 watt hours
1 100-watt TV 4 hours a day: 400 watt hours
1 50 watt radio 4 hours a day: 200 watt hours
1 87-watt philips respironics 8 hours a day: 696 watt hours
= ~2500 watt hours x 1.5 fudge 3750 watt hours
I'm not sure how to calculate well pump daily usage, it has a 30 gallon pressure tank. Plus other small misc things like charging phones and laptop etc.
I'm installing a security system that is based on 3 bushnell cellular game cameras with Lion batteries and each have solar panels so they don't need to be hooked to the system. This will allow me to have a remote security system that is self powered and will text my phone on movement. Also during hunting season I can easily move the cameras without having to move wires or power around. Shocking that there is good AT&T service on top the mountain but there is. I'll be hanging up solar powered motion lights too.
Planned System:
Magnum 4448 pae
Magnum MMP panel
8x6v AGM batteries 390AH Crown L16(or similar) - 18720 watt hours
(Panels and Charge controller later)
My Plan:
I believe the 4448 inverter is plenty big to run all 110v and well pump in bursts, but obviously not house A/C. I plan to wire it directly to the house panel to supply both 110 and 220v. You may be laughing at this point because I mentioned central A/C above, but just bare with me. Since the magnum has a 60amp, or 2x30amp feed in from the generator to pass through and charge the batteries and supply the house panel with power, my first question is by running the central A/C off generator only will the pass through on the magnum be sufficient? I know the 48v battery bank won't be CLOSE to even starting the central unit so I'll just run it off genset.
If the genset pass through will run the central A/C what problems can I expect? If the genset shuts down while A/C is running and the magnum tries to switch to batteries will the amp draw kill the batteries until the magnum can shut down or just pop a breaker? Is there any protection from this besides installing another house panel and isolating A/C and well pump on genset only?
I mentioned above that I will be adding panels and charge controller later(if possible). Since the magnum has a built in 30amp charger I figure until I install PV and midnight 150 I can just keep the batteries charged with genset. The generac can be started from the house already, and I'll wire in an autostart from the magnum. Does the magnum do a sufficient job knowing when to start the generator and charge, or should I go ahead and install the midnight with whizbang to kick on the genset? Genset is currently set to run once a month for 10 minutes but can be programmed to run weekly to keep batteries topped off while I'm not there. Draw on batteries while I'm not there should only be the magnum itself.
PV Panels
Since I'll be getting about 4 good hours a day I figure 16x300 watt panels will be good? That's 4800 watts x 4 hours = 19200 watt hours to match my battery bank.
I'm pretty much a newb at all this so hopefully my initial thoughts aren't too far off the mark. Later on down the road(5 years or when first battery set needs replaced) I'll look at 24x2v 1150ah batteries and a 48v mini split to replace the central A/C. Or just add another string of 8x6v and another midnight for that run.
Thoughts, concerns?
Moonie
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