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What portable energy system to build with this equipment?

 
pollinator
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Ive seen people building and advertising “portable” energy systems or generators. I have some extra equipment so am thinking of building one. I enjoy building systems. They are not really a complete generator if they don’t include the energy source, solar panels (or wind, microhydro, or ?). But, anyway, I have the foundation for a portable system using some relatively lightweight Lithium ion batteries, charge controller, and a inverter. A energy source, solar panel , wind turbine, or hydro turbine, can be added later. I have access to a awesome 460 watt panel. It would work nicely with the Midnite Solar Kid Mppt charge controller and the 7 Nissan Leaf modules if I wire them in series at 48 volts. The inverter is a Exeltech 48 volt, 600 watt, PSW. I have a extra aluminum hand truck they could go on? But maybe a box would be better?. Then use the hand truck to move the box. Or maybe a cart?
Using the term portable is a stretch. The batteries are about 45lbs alone. I’m estimating everything together in a box would be about about 80 lbs without the solar panels. Would this be better in a cart, rather than box or hand truck, with a solar panel attached??. I might need to sell it and want to build what the buyer wants. I guess if I build it they will come? Carts are expensive however.
I’d rather build a system than sell the equipment on Craigslist or eBay. But I guess that’s a option. It seems most people want to build it themselves and save money. Only the millionaires want a system designed and built. That’s how it seems. Paul is brilliant to use Kickstarter to build systems. And use them for educational purposes. Get the good energy (pun) out there.
 
pollinator
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It sounds like you want to build a UPS, the type that protects your computer/server in case there is a power outage.
I prefer one that I can plug into the wall and then when the power goes out. I can plug my laptop/electronics into it.
https://www.homedepot.com/p/Duracell-PowerSource-1800-Watt-Peak-Push-Button-Start-Quiet-Gasless-Portable-Power-Generator-DR660PSS/313518350

A 600W output means that I cant run any kitchen appliance (fridge/toaster/mixer), I cant run a saw or drill. So it is mostly just a jumbo cellphone battery pack that I can use to charge/run my laptop, phone, tv. It can only run some low powered desktop computer. In short it needs an upgrade.

Inverter 15A (120V) = 1800W. With that you can run most household devices/appliances
AC Charger, so that I can plug it into a regular AC wall outlet and charge it
Battery, for lead batteries with 0.25C discharge, I want 4x inverter capacity. So 4Hr x 1800W = 7200WHr, for Lithium that can handle 1C discharge just 1800WHr is okay
Charge Controller this is optional but the midnite kid that you have is perfect
Solar Panel wind and hydro isn't portable unless all you want to charge is a phone, 500W aka two solar panels sounds just about perfect.

But to answer your specific question
Inverter 5A (120V) = 600W. (4hrs runtime from a full battery at max)
AC Charger, missing
Battery, 7x 500WHr= 3500WHr, they are probably old so only at 80% aka 2,800WHr, a BMS is also needed
DC Charge Controller the midnite kid that you have is perfect
Solar Panel the 450W panel is good. 4Hr x 450W = 1800WHr (this will power the inverter for 3hrs if the inverter is running at max)
I think that the weight is good and with a better inverter it would be almost perfect.
 
pollinator
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I would put it in a box for sure, with the panel separate. Maybe a simple frame with handles or small wheels, for the panel alone? Easy to mount a box to a cart if someone wants a cart. Easy to move with a dolly. Easy to toss(gently!) in a vehicle... flexible.

Seems like a great setup to charge cordless tools with,  run a small fridge.. plenty of uses.

I would want more solar paired with that amount of battery, in my rainy clime...
 
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Jeremy,

I actually have an interest in building one of these myself.  And the name in misleading as they are frequently called “battery generators” which is an inaccurate term because by themselves they merely store and release energy as you properly point out.  By themselves they do not actually generate electricity.

I have small version of one of these projects running HERE:

https://permies.com/t/135729/permaculture-projects/Building-pair-battery-generators#1074905

I built this small, 12 volt device as a form of backup power for small electronic devices.  I also built it as practice to build something like you are describing.  For my part, I am planning on building mine in a rolling construction tool box.

This is a serious project but certainly an achievable one.  I am interested to see how this project develops.  Out of curiosity,  what is the amp hour rating of your battery?  The reason I ask is that in my future build, I will probably go with an AGM battery for longevity and ruggedness (and price).  I plan for the battery to be 100-125 AH batteries and, yes, they are heavy.

I am super interested to see where this thread goes,I hope to learn a thing or two myself.

Great work there,

Eric
 
pollinator
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.make sure you incorporate a BMS for the lithium cells to not over discharge them. Most of the rest has been covered above. If you are building a system using a midnite kid spring for the 2000 watt inverter...
 
Jeremy Baker
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David Baillie wrote:.make sure you incorporate a BMS for the lithium cells to not over discharge them. Most of the rest has been covered above. If you are building a system using a midnite kid spring for the 2000 watt inverter...


The Electrodacus BMS I have is rated for 12/24 volts not for 48 volts unfortunately. This is one of the biggest complaints about it otherwise it’s a amazing device. Any suggestions on BMS rated for 48 volts? Thanks
 
David Baillie
pollinator
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Jeremy Baker wrote:

David Baillie wrote:.make sure you incorporate a BMS for the lithium cells to not over discharge them. Most of the rest has been covered above. If you are building a system using a midnite kid spring for the 2000 watt inverter...


The Electrodacus BMS I have is rated for 12/24 volts not for 48 volts unfortunately. This is one of the biggest complaints about it otherwise it’s a amazing device. Any suggestions on BMS rated for 48 volts? Thanks


No good recommendations for a BMS unfortunately. Why not use the 24 volt configuration if you like the BMS you have? The kid will do 25 amps at 24 volt so it should cover the 460 watt panel...
 
Jeremy Baker
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I wish I could do a 24 volt system because I also have aVictron 24 volt inverter charger. However Nissan Leaf batteries only match the voltage of a 48 volt system.
 
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