Hello all, its been awhile. I searched but could not find a thread where people talked about their systems and their choices. As I do more solar design and install and less construction I enjoy hearing people out as to why they made the choices they made. For myself I prefer a grid interactive system if the grid is available as it cuts down on costs, I like a battery component, and I like a system that can operate hands off if you want it to. I still like lead acid although the tipping point for lithium is getting ever closer. So To kick it off here are the basics of a system I “rescued” recently It was wired wrong, programmed wrong and was not doing what the owners needed it to do.
Cheers, David Baillie
Voltage: 48 volt system
Solar: 2x 3kw solar arrays
CHarge controllers: 2xOutback FM80
Inverter: 2x Schneider 6048SW conext Hybrid inverters paired
Batteries: Originally 32x L16 with 80KwHrs of storage
Currently 16xL16 with 40KwHrs of storage highly sulphated in need of replacement
Back up: 60amp grid connection, 8Kw Diesel autostart generator
I’ve been doing some work recently at a localFarm trying to bring their grid interactive system back to life. The system itself is about 10 years old and has 6Kw of panels on two arrays, a pair of Schneider’s first generation conext inverters and originally a wopping 80KwHr of battery storage. It was sitting turned off for almost 2 years as they tried to find someone to fix it. I do like a challenge! So this is something unfortunately you come across in the industry; a system that was quite pricey but set up wrong for the clients needs. There are lots of factors that go into a successful design but the first one is always listening and observing, very permaculture in a way. In this case the original designer chose to ignore the fact that there was a grid already present and chose to set them up as if they were totally offgrid. A backup generator would recharge the batteries when there was not enoughsun and the large battery bank would store days worth of power but the solar arrays were not big enough to ever fully charge it… They never bothered hooking up the grid to the inverter or setting up the inverter properly or explaining the system to the people paying for it and running it. The consequence was a grid interactive inverter set up with one arm tied behind its back and clients left to figure things out as best they could a generator that ran all the time and a battery bank that failed from being sulphated from undercharging. After some rewiring, and mostly reprogramming of the unit, the system now uses the grid if there is not enough sun, keeps a smaller battery pack charged fully, uses as much solar power during the day as possible and in the case of an outage uses its battery reserves but then can turn on the generator to recharge. All that without any input from the end users unless they want to intervene. As it should have been from the beginning… It was a rewarding experience though a little frustrating. Frustrating because some really nice people were set up to fail due to lack of knowledge, greed or close mindedness from the installer.
Check out EG4 systems from signature solar. You can get a 5 kW/hour LifePo4 rack battery for $1400 bucks you cant touch that price with lead acid and it will last 20 years. The EG4 6000 EX 48 volt inverter so far has been a work horse. We are able to run both our 220 welder and our CNC plasma cutter from this system. The only thing we cant is run the air compressor, so we do run our generators when running the CNC machine.
Looks very interesting Matt. I’d have to dive deeper to see their certifications. The transformerless all in one units are definitely coming up strong. I know a transformer might help your compressor start…
And still with almost no gasoline fuel use. Matt you have built for your self a stable soild electrical system that you can keep your factory running, when others are shut down for lack of electrical power.
Lasting 20 years? That should pay for it self in that amount of time in power savings cost from grid power compainies where you live.
Can you show us the solarray panels you are useing?
It can run the air compressor just fine; it just cant do it with all the other equipment running at the same time. This is the 6000 EX this is the version that has a transformer. The 6500 is the lighter version.
No solar yet I dont own the property so I will be limited to how much solar I can install. We still run gasoline here, but now much less of it as nothing is wasted. That power goes directly to battery storage and what is left goes direct to shop. Versus before any idle time running lights the generators gulp and gulp fuel down.
This has cut down fuel consumption by 60 to 70%. Before to have power those generators had to run full time. Now in the morning we go two hours on battery power and then fire up the generator or generators and run a full charge. Takes about 3 hours. If we run the CNC machine then we run two generators to lessen the load on everything and run the air compressor. So yeah we have cut generator run time by quite a bit.
Under $5000.00 that includes an outdoor RV box that is used to distribute the power. Rather than feed power all the way to the shops panel for the 220 circiuts this panels feeds that directly and greatly shortens the distance. Then the shop power is reduced to just lights and low power tools like our drill press, lathe, saws etc. I also have a 2500 watt inverter that is part of that cost. This is in case we over load this will keep some lights on while keeping the CNC machine from crashing.
I should note: we have two of the 5 kW/hour rack batteries. So 10 kW/hours total, the EG46000EX the outdoor 8 circuit panel box, a 30 amp breaker for gen power supply, about 40 feet 10 ga. 4 wire cable and the the 2500 watt inverter. All for less than $5000 bucks.
Thanks Matt, that is only a little more expensive then a DIY LiPo4 battery. You cant win anything by doing that yourself.
We have several systems running overhere. Started with a 3600 Wp, 195 Wp panel, system that had to move last summer for a 8010 Wp, 445 Wp panel system. All the systems a mono, only one 6600 Wp poly 275 Wp panels. Another old system bought used in 2013, 250 Wp mono 5000 Wp. And a original 12 400 Wp panel lost one panel in a storm, got it for free from my friend. Now 3600 Wp.It is total 23.210 Wp. If my friend showes up this week I hope to install 3 more panels in the corner of the roof and it will be 25 kWp. All panels are facing south 20 degrees. Following a guy on YT that is measering the best angle, east west etc. It turnes out that panels facing south on 75 degrees deliver the rated Wp. That makes me think to keep installing PV. Roof is full, so next step is wall mounted. Good for winter time.
On another location there are 24 panels east-west 10 degrees, Two Growatt inverters.
Waiting for the bill and expect €3000 refund. Easy money ROI is less then two years.
And last summer installed a Victron system for peak shaving. Three phase 400 V, 15 kVa with a DIY LifePo4 10 kWh battery. Battery is doing ok but to small for real life use. Thinking/looking for another option now.
All cheap grid tied inverters. Victron keeps them in the air in case of a grid failure.
Yeah pricing on used second hand batteries is too high. Not sure if the resellers cant get better deals or what. But its not worth DIYing a battery any more, when new cost are only slightly more and you know what you are getting with warranty spanning out many years in most cases.
I’m convinced the auto makers are rebuying their own packs as a second life option for grid support or to keep the price high… At the price you listed Matt as an off grid generator setup lithium makes perfect sense. As a grid connected batteries for outages situation where it does not cycle and the pack must live outdoors ( Canadian electrical code 2021) in residential settings a lead acid a solution still works…
I have about 80 used solar panels sitting all over the yard, on top of the patio, and on top of the greenhouse, and a few laying on pallets or just on the ground. This all started with 4 panels on a tube steel frame in 2014 using Enphase M250 microinverters. The remainder are with used M215 microinverters, and used cabling, all DIY. Panels are from SanTanSolar.com are cost about $50 each. I have three $33 used cracked vinyl panels hooked directly to a 220 volt element of my 50 gallon water heater which gets it to a max temperature of 150 F. No MPPT, no controllers…just 3 panels laying on the grass hooked directly to the heater. Another 100 watt panel ran a 24 volt water pump most of the summer. A pond bubbler is run from a 14 volt LFP battery, that is charged with a 100 watt panel and a PWM charge controller ($14). The newest project is a solar powered mini-split from Signature solar (EG4) that has yet to be installed. EG4 Hybrid AC/DC Solar Mini Split Air Conditioner Heat Pump | 12000 BTU | Direct Solar Input - Signature Solar
This, along with the water heater will run whenever the sun shines, whether or not the grid is up.
These panels run my 10,000 square feet of shop and house, as well as charge our two electric cars, and still earn money from the co-op electric every month.
My gasoline powered inverter generators all have plugged up carburetors, so the 12 volt LFP drop-in batteries with a 1000 watt sine wave inverter are substituting quite well, running pumps, small air compressors, electric saws, electric hedge trimmers, and the freezers in an emergency.
I really like that direct solar mini split… Our home array right now is only 3 kw that we installed on an existing shed while we built the house. I’m currently planning a project for the spring to incorporate a larger array. The current house is all electric and we are vulnerable to a power outage as we cannot run the large heat pump on our inverter. So far we’ve had a 36 hour outage. The house is super insulated though so we only dropped 1 degree Celsius with outdoor temps of -6 C. I’ve decided to use my existing gear for now and not install a monster system so that means we will need to figure out a heating option. A small mini split would fit the bill perfectly.
You would benefit from one of the new heat pump water heaters, that are supposed to covered with the new IRA tax credits since you have warmer air. They use less electric, and you won’t have to worry about scalding as much. I am not saying you are doing anything wrong and it is a neat set up.
You can actually hot air weld vynal to fix the cracks. I have a cheapo hot air/soldering iron that is temp controlled and use it to weld plastic. (don’t breathe the fumes). Mine is a jcd 8898, which I saw the teardown video for, and it had stuff to electrostatic discharge for electronics but now there are 8898 knockoffs for 18 bucks on aliexpress. I bought a set of soldering tips specifically to use for plastic so I don’t mess up the ones I use for electric components. It is small so it can be stored easily with the rest of the soldering stuff.
I think the tipping point for LiFe is already here for storage if you are looking at the cost per cycle. And they don’t suffer from damage by over discharging. They have good output to 80% DoD, where lead acid drops voltage and suffers damage during disharge.
I don’t think that is the case. I think the gray market has a lot of off-gridders swiping up battery packs, as well as refurb places for the automotive packs. Then you have recycling facilities that recycle all the metals in them. Then lithium has spiked in price over the last couple of years. There werent a lot of electric vehicles sold 10 years ago so the supply is low to begin with, but then LG recalled all the batteries for the Bolts (Kia and a few others were affected as well) for a oddball manufacturing defect starting a random fire, (two defects had to occur in the same cell) so all those packs go straight to recycling.
For an outdoor system, LiFe may not work well because of the cold environment. You could bury it below the frostline like a well pump house. They are extremely light so moving them is easy.
You might mount them to a trailer. A gutted camper would be almost perfect. Then you have outdoor storage as well as some elevation for snow. It wouldn’t provide all power, but it would take a chunk out of your fuel bill as well. you may not have the space for it though. But with the IRA coming, it would seemingly be a tax deduction as well.
you could probably get more then 500 watts. You can get a single panel with like 400w. The double sided panel do over 500, but I don’t think those would work well because they pick up ambient/reflected light on the backside. They might work better for an east/west mounting.
There is actually a company that makes roll up awnings for RVs.