CHEAP DIY 2kw Adjustable Solar Array For My Off Grid Homestead
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- Опубліковано 16 тра 2024
- I'm building a large upgrade to replace my 800watt panels and 12 volt batteries. this wasn't quite enough to keep my fridge powered for more than a day or 2 with clouds. And Now with Jon moving onto the property as well he will need some power too. so we're adding another 1200 watts of solar panels to the system and upgrading the batteries to 24 volt Lifepo4 batteries.
I made sure to make the panels adjustable so that they could get the maximum sunlight in all seasons. - Розваги
Yeah an electric water heater would be that giant electric draw you were talking about.
Having built one of these myself I would suggest the following. (1). Ditch the cheap charge controllers they will cook your expensive batteries. Go Victron its worth it, you have the option of using a Rasberry Pi to manage the system and you can add relays to automatically turn things on and off using logic rules for example turn on a heater/cooler when the battery is full. Victron can also be set not to charge your batteries when its too cold. (2) voltage drop is always going to be in issue over that distance so why not connect both solar new solar arrays in series and send 200v 2a up the hill to the shack and have the inverter and battery bank there. That way the battery bank will be kept warm in your heated living space. Voltage drop increases with the current draw. (3). Lay the cable in conduit. (4). would have been better to connect your 2 new arrays together and counterbalance it in the middle rather than hinge and the bottom, that way you can make 1 much stronger frame. (5) and this is the big one get that thing properly anchored into the ground or it will blow away in the first storm. - With solar they are called opportunity loads rather than dump loads, you will need a way of testing the generation conditions by turning on a load and seeing if there is enough solar generation to run it without putting the battery into a discharge state. Also Bi facials are expensive, used 260W panels are super cheap now so much so I have used them as a roofing sheet rather than buy OSB and felt. Good luck with it
Oh that's some Michael Kiwanuka playing at 1:50. Loving to see the progress bro, keep it strong!
You don't need a dump load, you just need to configure your charge controllers properly. I see you are using several different charge controllers and if you are triggering an overcharge condition and the BMS is shutting down, then lower the charge settings by maybe about 0.2v on each controller. Those cheapy blue PWM controllers are terrible for this and quite often allow way more voltage out to your batteries than they are supposed too. I've had to throw away a few of those things because of the voltage spikes getting through. I know money is tight, but I would switch that out ASAP with something a bit better or eventually they are going to ruin your batteries if they are over charging... But all this dump load talk is not what you need to do and is more necessary with really old wind turbine type stuff. Get a REAL mppt (not one of those blue ones that look the same and are marketed as MPPT because they are not). Good luck.
Electric water heater is a great dump load and gets you free hot water, or at least helps to heat it. heating elements are available in any voltage and cheap it's easy to convert them.. You went to a lot of trouble to get max from your panels and it's getting wasted with the cheap controllers.. Get MPPT controllers.. You seem to have all the basic info and you'll learn about implementation as time goes.. You SHOULD Shower everyday.. AND, hinging the array in the center (like a teeter-totter) instead of the bottom hinge like you did, makes them much easier to adjust the angle every month and also to dump the snow if needed.. possible problems Blue tarps are NOT water-proof.. keep an eye on it... That 12 ga wire is going to catch fire.. make sure it's fused and feel it from time to time,, if it gets hot,, you have to do something. Wire is expensive so always keep an eye out for deals new or used...
If you placed mirrors under the array you could bounce sunlight onto the back of the panels.
Awesome project.
I would have took the money for cinder blocks and got ground contact 4x4 and some concrete to go with your cement mixer in the background and concreted those into the ground.
Fuck yeah, just left the Matrix
Hell yea brother!
A few comments.
A single 60a output MPPT would handle all your panels if they are charging a 24v lifepo4 bat bank. I installed a Makeskyblue one on a boat, which now costs $85- $100 and can handle 1440w PV power going to 24v bat bank. Generally 95% eff and max PV voltage around 110vdc- so wiring with serial /parallel arrangement is needed. There are other brands as well. The PWM? controllers are efficient in some ways, but waste pv power if the voltage is more than approx 30% above the bat voltage (32v to maybe 36v for a 24v bat bank)- so if PV voltage going to a PWM is over 32-36v, you are losing charging power.
Bifacial a good idea- more power per sq ft and they tend to shed snow when sun starts to shine- reflected sun hits bottom of panel, produces power and heat and heat melts snow. Some DIY solar homeowners have found a combo of angled bifacials and vertical ones (one side faces E, other side faces W) improves the overall system efficiency by catching early morning and late afternoon sun.
Mount some reflectix on a sheet of OSB or plywood and place on the ground under the back of the panels.
For the excess energy problem, couldn’t you just have a switch disconnect the panels automatically over a certain battery charge percent?
why? charge controllers do exactly that already.
Id need some kind of circuit to detect the battery voltage and disconnect and reconnect from the system. that takes some doing
those panels will continuously make power and if the batteries are too full for the charge controller to send the power. the power has to go somewhere. It could potentially fry the controller or overcharge the battery.
@@janklabs so why do you use CHARGE CONTROLLERS at all?
@@broniusale5987 The controllers convert the voltage to what the batteries need and monitor them.. The extra energy can be dumped into something useful.. An electric water heater is perfect
The insulation you installed in your battery compartment wont do ny good if it has air infiltration. If air can flow around the insulation it will be worthless. that compartment must be air tight.
A cheap power dump would be a hot water heater. Wire it up with a circulating pump in a closed loop system. When the batteries get full it powers the hot water heater and the pump which will circulate the water to cool it down so it can be heated again. Of course you need the right charge controller to control this circuit and an insulated building for winter time unless you put the water heater in your house. I saw it done in a foreign country where the whole village ran power from a water generator system consisting of three water heaters, one for each generator. Of coarse their system took the water from the river then dumped the hot water back into the river.
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Most people watch solar videos to see the wiring 🤣. I'm just saying.