SOLR GENERATOR

[SemperParatus]

I had commented on a post about a solar generator I put together and was asked to post about it with pictures.  The system I put together is carried in two heavey duty steel garden carts.  One cart carries 9 130 amp deep cycle lead acid batteries and a large ammo box that contains the charge controller, charging station, 1000 watt inverter and 3000 watt inverter.  The second cart contains 4 100 watt solar panels, ground rod, accessory cords and hand tools to put the system together.  I didn't set up the system completely but I think you can get the idea, this was intended to be a semi-portable unit that is used during prolonged power outages.  The system will run two refrigerators and two freezers as well as a charging station for electronics.  When I put the system together I tested it by running a 250 watt heating lamp for 8 hours and then used the solar array to recharge the system which took about 10 hours to fully recharge with partly cloudy skys. The total cost of the unit was less than $1,100.00, the majority of that cost was in batteries.  I leave the system on smart chargers and perform a load test every 3 months on each battery as well as check the batteries for water levels.  Evey six months I check each battery cell with a hydrometer to make sure all cells are performing to specs.  So far I have used the system three times, the first time I used it we lost power for four days and it ran flawlessly. At this time the system is three years old and I have not needed to replace any components or batteries.  The main advantage of this system is that it is portable and can be set up where you need power in about 20-30 minutes.

[mechmedic]

I am seriously interested in doing something like this. Hurricanes are a real issue where I live and this seems like a much better answer than a gas powered generator.

[Kbop]

its a good option for storm resilience - if you can protect it from wind and water.
same problems with a liquid or gas fueled one too. 

maybe its time for me to look at methanol run fuel cells again and see how they are coming along.

moving along - these burn methanol and recharge a battery.
https://www.efoy-comfort.com/which-model#overview

[bennington.camper]

I had commented on a post about a solar generator I put together and was asked to post about it with pictures.  The system ... 

Hi - I design PV systems with battery backup for a living and have been doing it for over 15 years now, so might be able to be a resource.
It is good that you took on a project like this, and are satisfied with its performance, however if someone were to duplicate it, I have a number of improvements.
I just wanted to put this post in the thread in case someone else is thinking of doing the same thing...I would suggest additional research.
Just trying to be helpful, not critical.
Glenn - NABCEP Certified PV Installation Professional

[mechmedic]

My area isn't in a flood plain so I'm not too concerned with water resistance. Just quiet energy.

[pkveazey]

Solar Power is a subject near and dear to my heart. I'm right in the middle of having a metal roof installed and its real expensive. I've tabled my solar plans until I can save enough money to install a basic solar panel system. I don't see me investing any more than 3 or 4 K but I've been looking at the battery portion and its tough to decide what to buy. At first, I thought about deep cycle recreation batteries but I'm now leaning more toward the latest and greatest Lithium batteries. Why? Well, its been my experience with Lithium that once they are charged up, they don't leak down very quickly when not in use. The area where I think I'm going to have trouble is an inverter that I want to tap into my panel box at the 240 volt buss, like I do with my generator, and not have a rinky-dink 120 volt setup where I'll have power at just a few locations in the house. My plan is to mount my panels on the new roof and build a small battery and inverter house right next to the house. I don't like the idea of having the batteries inside the house. Anyone having any pointers to suggest on what I plan would be helpful.

[JohnyMac]

I too looked at powering my whole house off solar. Because of my Lat. the two salesmen that bid on the project told me that I would need back-up electric for 3-months; Dec, Jan and Feb. which is no big deal. Both estimates came in at ~$13K.

I forget all of the details but I do remember the inverter was going to be a 48 volt one. Not 12 or 24 volts.

Anyway, based on our current solar power set-up & needs, if the grid goes down, we will be just fine without spending $13K. We will use our Aladdin lamps for light, our gas stove for cooking, our wood stove for heat and a additional cook top, and the 12 volt system we do have. We use our 12 volt system for water delivery, juice to run our on demand water heater, charging batteries for our flashlights and such and communications, e.g Sirius radio, lap top, communications, etc.

The only hole we have is refrigeration. I am doing research now on alternate methods of cooling, e.g. propane and kerosene to be specific.   

[zeerf]

The only hole we have is refrigeration. I am doing research now on alternate methods of cooling, e.g. propane and kerosene to be specific.

I have been looking allot into root cellars lately. I really want to get a few of the cheap options I have seen built but assume for best results I will need to make a nice investment.

[JohnyMac]

Zeerf,

root cellars are great! There are some great designs out there on the interwiz to model yours from. Many moons ago, we lived in a house that the main part of was built in the 1750's. Along with that house came a root cellar.

The root cellar was about 10x10 feet square and about 7-feet high in the center and it was domed like so about 6-feet at the ends. You accessed it via a wooden cellar door like thisthis ad. There were meat hooks that slid along a metal pipe at the rear of the cellar and shelving that was made out of wood and some more modern metal ones. Lighting was a kerosene single wick lamp. Leading from the door to the cellar was 10+ stairs. I forget how many however they were made up of blue stone (Slate to you non-PA folks). The temps ranged from 45 to 50 degrees depending on the time of year.

We never used the root cellar for its intended purpose of food storage. We did play in it though. I remember sending my brother down to grab something and while he was down in the cellar my buddy and I threw firecrackers into the cellar.  My brother wasn't happy however being 7-years older than him, he didn't protest too much. 

[bennington.camper]

I too looked at powering my whole house off solar. Because of my Lat. the two salesmen that bid on the project told me that I would need back-up electric for 3-months; Dec, Jan and Feb. which is no big deal. Both estimates came in at ~$13K.

Your Latitude? Are you in Alaska? Or do you have significant shading of the array the array would go? Or perhaps the location chosen for the array is not large enough to support an array sized to meet your winter needs (low angle sun and shorter days).
I am unaware of any latitude in the contiguous US that would require battery backup during those months.

Most (but not all) battery based PV systems that support more than a few hundred Watts of load are 48VDC. The most economical way to get into batteries remains flooded lead acid, more like the floor scrubber or golf cart battery variety. If you have the means, LiFePO is the current flavor - it offers much deeper discharge ability without harming the lifetime of the batteries. However it has a high upfront cost, and requires specific hardware to charge and safely discharge.. Most equipment manufacturers are still struggling to catch up.
I am aware of a few LiFePO batteries that operate at a much higher voltage, but require specific inverters to operate. Pika Energy operates their batteries and PV array at 380VDC. Solar Edge with their StorEdge inverter pairs with an LG Chem RESU10H Energy Storage System (ESS) and operates at 350-380VDC also. Stand alone systems like the sonnen eco are self contained and have an Outback Radian inverter along with Panasonic Li batteries in a sleek cabinet like a refridgerator. They are not designed to directly work with solar, more like a whole house backup system, recharged from teh grid or a generator, however using AC coupling can be interfaced with a purely grid tied system that will function when the grid is down.

[bennington.camper]

Solar Power is a subject near and dear to my heart.
 Anyone having any pointers to suggest on what I plan would be helpful.

LiFePo would be the way to go if you can stand the sticker shock. Their ROI exceeds that of current lead acid (LA) technology.
All the systems we have installed to date use either flooded LA, or sealed LA and work fine. FLA requires a sealed and positively vented enclosure, where the SLA do not. Tesla and LG Chem are both ESS units that are NEMA 3R listed so can be mounted outdoors, however Tesla has very stringent requirements for their systems.
All the major players in the US marketplace interface with the grid at 240VAC. Outback, Schneider and SolarEdge to name a few. All can be grid interactive, and have models that can also island if the grid were lost, or doesn't exist. It is mote of a challenge to match the ESS to the loads and duration of use than how to do it these days.

[pkveazey]

Yep. The Lithium Potassium seems to be the latest and greatest thing. I live on the 37th parallel and mean exactly on the 37th parallel(1,500 feet north of my house). I'm good for all year round solar. My house is total electric but I rarely use more than 1000 KWH per month. This month's bill was for 657 KWH. When I use my gas powered generator(10KW max, 8KW continuous), I turn off all the heavy loads and run everything else in the house with no problems. When I need hot water, I turn off the well pump breaker and turn on the hot water heater breaker. When the water is hot, I turn off the hot water heater breaker and turn on the well pump breaker to pressurize the water lines and I'm off to the shower.  It doesn't take long to figure out how to manage power needs. I can even run my Heatpump/Air Conditioner as long as I just use it for Air Conditioning. I can't use the Heating part because of the Helper Coils. They draw 50 amps and pop the breaker on the generator when they come on. The orientation of my house is perfect for setting up solar panels. The front of the house faces almost exactly due north so the southern exposure is perfect for setting up solar panels. I have no plans to go total solar and spend 10 to 15 thousand for off grid, but I plan to use solar powered batteries for making life worth living during a bad situation.

[bennington.camper]

Yep. The Lithium Potassium seems to be the latest and greatest thing.

LiFePO are Lithium Iron Phosphate technology...

[pkveazey]

Yep. The Lithium Potassium seems to be the latest and greatest thing.

LiFePO are Lithium Iron Phosphate technology...

You're right. I forgot that Potassium is K.

[Kbop]

for stationary applications the nickel- iron battery (aka Edison battery) is a long term fairly stable chemistry.
NiFe batteries have an excellent track record for long term continuous use and don't tend to create alkali metal fires when mistreated.

drawbacks - they are expensive, bulky and very heavy - they wouldn't be my choice for a mobile application.
- funny that is their biggest use - mobile platforms, usually ships and trains.

https://ironedison.com/nickel-iron-ni-fe-battery
12VDC, 1,000 Amp Hour, 10.8KWh usable, $10,937.50 - rated for 30+years

assuming 30 years of offgrid use - its worth it.