diy solar

diy solar

Hello New Friends -- Need your thoughts

Your frig and freezer do not run all the time it is an intermittent load like on an hour off for two hours. Unless you leave the door open.
Excellent point. I decided to use the max wattage to ensure I didn't under-estimate. But, I do understand your point. Thank you.
 
No big motors there, no A/C or water pump. Garage door opener might be 1/2 HP induction motor, that's the biggest surge (assume 5x nameplate current.)

Old garage fridge may be much bigger consumer than new fridge, depending on how old.
400W is surprisingly low rating, usually defroster or ice maker has higher draw. But my old one is about 400W for the motor.
You may be able to reduce Wh consumption with new appliances. But I'd suggest saving the old reliable one for backup.

I figured a toggle switch between two or four outlets would be a way to enforce only one heating appliance at a time.
 
Check out this guy. He repairs the generator types mentioned here and may have one to sell or suggest a good one to look for. He has been doing these repairs for many years and after watching him on youtube on TV he really seems to know his stuff.

Here is an example of a Powermate generator he fixed.
Oh man, I love that guy. I've learned almost everything I know about the nuances of generators from him.

I have watched every video he's made, and some of them twice.
 
I'm thinking I need to learn "energy management" techniques that would allow me to use either solar or fuel more efficiently. I provided the list of items I think we will want to have access to during an outage -- but, obviously, we wouldn't be using all of them at the same time. I would avoid, for example, running the microwave and toaster oven at the same time. And, as noted, I'll skip the HP.

Perhaps the solution is a combination of fuel/solar. I hate to run a generator at night -- annoying me and my neighbors. Maybe that's when I could use a solar setup. And, assuming the outage lasted a while, I could use a more cost-effective generator during the day (not the 9000 unit). Does this make any sense?

Yes, exactly.. Energy management is important off-grid or when the grid is not available. Grid power spoils most of us.

The best solution is a combination of fuel and solar, and that is exactly what our family has. If I didn't mind the cost of replacing our solar storage batteries every 5 to 10 years, I could easily tell the power company to come get their meter and go completely off grid. And that's saying a lot from a guy who runs an air compressor, sandblast cabinet, plasma cutter, mig welder and a house full of energy sucking appliances.

If you wanted to sort of "split the difference", I would suggest 4 kW of solar, 10 to 15 kWh of battery bank, and one of those little 2000 watt Honda suitcase generators modified to run on both gasoline and propane.

With a setup like that, and proper energy management, you could probably ride out a month long power outage without any major sacrifices. Of course, all that stuff is going to be a lot more expensive than just getting a generator for the whole house. The downside is cost, but the upside is that in the case of a massive hurricane or other disaster, the solar route will keep you going LONG after fuel for that generator has disappeared.
 
You guys have been soooo much help and I sincerely appreciate it. This area is clearly not one that I'm comfortable with or really understand. I have the hardest time getting my mind around, watts, amps, voltage -- even with the water hose illustration. Sorry guys!

For example, I was thinking about how an 1800 watt appliance (like say a microwave) would draw energy from a battery. So I thought, well, I'll divided 1800 by 60 minutes to figure out how many watts are drawn every minute. Obviously, I don't run a microwave for an hour -- more often for a minute or two. So, 1800/60 =30 watts per minute. Wow, not that much. But then I thought -- wait -- even if it's only on 1 minute it's still drawing 1800 watts!!! So, I just don't know how to figure out how long a battery would last. Could someone please explain this to me?:oops:
Maybe you could use my microwave example and a battery that's rated at 3600 watt house.
 
You guys have been soooo much help and I sincerely appreciate it. This area is clearly not one that I'm comfortable with or really understand. I have the hardest time getting my mind around, watts, amps, voltage -- even with the water hose illustration. Sorry guys!

For example, I was thinking about how an 1800 watt appliance (like say a microwave) would draw energy from a battery. So I thought, well, I'll divided 1800 by 60 minutes to figure out how many watts are drawn every minute. Obviously, I don't run a microwave for an hour -- more often for a minute or two. So, 1800/60 =30 watts per minute. Wow, not that much. But then I thought -- wait -- even if it's only on 1 minute it's still drawing 1800 watts!!! So, I just don't know how to figure out how long a battery would last. Could someone please explain this to me?:oops:
Maybe you could use my microwave example and a battery that's rated at 3600 watt house.
You are confusing watts with watt hours, if you run your 1800-watt microwave for 2 hours it will consume 3600 watts hours. If you run your 1800-watt microwave for 10 minutes it will consume 300 watts hours which gives you 3300-watt hours left.
 
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You guys have been soooo much help and I sincerely appreciate it. This area is clearly not one that I'm comfortable with or really understand. I have the hardest time getting my mind around, watts, amps, voltage -- even with the water hose illustration. Sorry guys!
There is theory and there is reality. Today purchase a Kill A Watt and measure over several days to confirm the real power requirements over time. It will do the calculations for you.

Take care measuring the fridge & freezer over time. The power draw is normally low, but during the defrost cycle the heaters can cause the power to spike. I would log on a daily basis to catch the when the defrost cycle operates.
 

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If you wanted to sort of "split the difference", I would suggest 4 kW of solar, 10 to 15 kWh of battery bank, and one of those little 2000 watt Honda suitcase generators modified to run on both gasoline and propane.

PV can be so cheap ... keep your eyes open and you might be able to pick up a second 4kW of PV for $1000, maybe less. One short pallet, or less space standing on end; about 8kW can fit on one pallet.
It can ride out poor solar days better. Or in hurricane country, ready to replace destroyed array as soon as the wind dies down.
 
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You are confusing watts with watt hours, if you run your 1800-watt microwave for 2 hours it will consume 3600 watts hours. If you run your 1800-watt microwave for 10 minutes it will consume 300 watts hours which gives you 3300-watt hours left.
Thanks, Labeeman! Looks like another passion of yours may be bee keeping??? I've watched a few videos on the topic and find it fascinating. Not for me, but I admire those who enjoy it.

Regarding my initial question, I got to thinking just as you suggested. If I have a battery that has 3600 watt hours and my appliance uses 1800 watts, it should be just a simple division. And, for realistic purposes, I would multiply the 3600 by .9 just to account for some inefficiencies.

Anyway, assuming this is the correct way to analyze this mess, I just realized that a 3600 watt hour battery would only power my essential items for about 2.5 hours!!!! "I'm gonna need a bigger boat" (battery)! I'd like to at least get through a single 24-hour day.
 
3600 Wh / 1800W / 90% = 2.22 hours run time (incorrect)

3600 Wh / (1800W / 90%) = 1.8 hours run time (correct)

Microwave? Should be good. Unless you're using it to cook a turkey.
 
Thanks, Labeeman! Looks like another passion of yours may be bee keeping??? I've watched a few videos on the topic and find it fascinating. Not for me, but I admire those who enjoy it.

Regarding my initial question, I got to thinking just as you suggested. If I have a battery that has 3600 watt hours and my appliance uses 1800 watts, it should be just a simple division. And, for realistic purposes, I would multiply the 3600 by .9 just to account for some inefficiencies.

Anyway, assuming this is the correct way to analyze this mess, I just realized that a 3600 watt hour battery would only power my essential items for about 2.5 hours!!!! "I'm gonna need a bigger boat" (battery)! I'd like to at least get through a single 24-hour day.
Yep, beekeeping is my main breadwinner I have been doing it for 35+ years before that it was electronic tech my last job was for a power plant. I am in retirement mode with the bees.

Another monkey wrench in figuring this all out is no load power draw of the inverter can be as high as 200 watts to as low as 25 watts do not believe the specs as most lie about that.

My battery is 55kwh and with lite loads will last me for 2 days No AC and Heat just computers, lights, dishwasher, MW, icebox, freezer, and TV.
for my ACs I have 2 one ton inverter window units for the summer I ran them all summer off-grid to my liking.
 
Thanks for the correction, Hedges!

Gotta love beekeeping, Labeeman. I too, retired from the utility company. Worked for Southern Company for 33 years. Was always in the corporate office so never really learned much about electricity - isn't that a hoot!

I'm not going to be able to use the EcoFlow Delta Pro units to cover my needs. I think it would be way to expensive. Each 3600 WH unit cost about $2800 and only covers my essential loads for about 2.5 hours. I will have to build my own power bank somehow.

Would using EG4 inverters and batteries be a cost-effective way to go? What other options would you suggest? Honestly, I don't want to use a gas/LP generator if possible. And, maybe 24 hours is too much to shoot for -- perhaps 8 hours is more realistic. We do have very reliable power here -- but, of course, with a major hit from a hurricane all bets are off.
 
Please don’t waste your money on these Chinese junk boxes the 1st generator. I bought ( bilt hard) did well for 1 month. Then when it acted up it ruined. Sulfated $2000 worth of my rv batteries, took 2 months dealing with these idiots from China you get 1 sentence every 24 hrs on an email response. So it takes 1 month to resolve / return this pos, then the next brand I bought runs ok until it doesn’t and the propane regulator leaks so that cost me 200 of wasted propane that was August now it’s dec but guess what they still never resolved that problem . I have all the emails about it and still no new part. I emailed them a video they req of my electronic leak detector showing the propane regulator leaking. They say they will send new parts out by Dhl but never did .. Now they have passed on helping me and say the useless California service center will expedite a replacement but that doesn’t happen either. This is after another video and pics of another issue. Fuel dripping from air cleaner box to carb inlet . And a 3rd issue is a full clean oil change that still didn’t resolve a low oil light/ no start for 3 days and a brainless service center that doesn’t know where the low oil wire is located to disconnect it so I can start it . They keep sending me the same pic of the wire which I keep responding to tell them that’s not my generator 7250 I don’t have any wires or sensor like the pic shows . So the generator has so much vibration that the main battery wire harness is being cut through by laying against the metal and that’s with the wire loom covering over the wires how many other places is that happening to ? And this engine has way too much noise it doesn’t sound good to my ears As A 30 year Ase master auto technician…. So my advice stay away from all this junk take a road trip and buy a good used generac with a real USA industrial engine w/ a pressurized oil system with a spin on oil filter and a true continuous output vs this BS junk that’s flooding our market I have such a unit but in storage and thus needed a quick on the road unit for my rv trip . Anyone wanting to see my emails to confirm all I say is welcome to see them .
 
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