solar power systems

vaskeet

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has anyone gone to a whole house solar system with battery backup. I am looking into it and looking for advise from people who have done it. looking at cost savings and any pros and cons
 
I looked into it. Pricing on the cells is still way higher than it ought to be. Your break even date is about the same as the life expectancy of the cells.

The only people who make money are the people who sell you the system.
 
I wouldn't try to run a house designed for 110V using solar panels and batteries. I would instead replace the lighting and as much of everything else with devices made to run on 12V, and set that up as a separate system powered by solar panels and batteries.Ya gotta keep things seperate.
 
I wouldn't try to run a house designed for 110V using solar panels and batteries. I would instead replace the lighting and as much of everything else with devices made to run on 12V, and set that up as a separate system powered by solar panels and batteries.Ya gotta keep things seperate.

Yep and LED lights are plenty bright at 12volts too.
 
has anyone gone to a whole house solar system with battery backup. I am looking into it and looking for advise from people who have done it. looking at cost savings and any pros and cons
With good solar panels your payback is about 30 or more years and the panels will be useless before that time. If you roof mount panels and they need to come off you can buy a new roof also. Then you need to think about the batteries. It’s a hard no for me unless it was a tiny cabin for lighting and heating supplement.
 
We had a tech talk at work about people who had done whole house real deal commercially installed solar. After listening to their stories, it solidified that it's still not a viable thing yet if you believe in a positive ROI. The rebates are scams; there are a limited number of them and you have to sit on a web site and mash the "submit" button like a monkey to try to get in at the exact time Duke releases the rebates or you don't get it... it's like concert tickets or something but only 10 seats and 1000 people trying for them. Tax credits aren't all that good, and really the subsidies are just driving the prices up, just like any time the .gov tries to fiddle with the markets.

Duke at el want to sell you whole house... but all it does is feed power to the grid. All the power comes off the grid and if the grid is down your solar is doing nothing. The 'spin the meter backwards' thing isn't quite correct anymore either. You sell power to duke at whatever the rate is, and they sell it back to you at rate + tax. So even if you generate 100% of your own power needs, you're going to pay the tithe to the .gov every month. No electricity bill indeed, but you still gotta pay unless you generate way more than you use, and then your system is HUGE (or you don't run a dryer).

I've done my own system as a trial, and I've learned that:

- separate lighting is the way to go, doing 48v DC to 110v AC conversion and trying to be "normal" is expensive at scale
- don't run 12v systems. I did, and the voltage drop moving the power anywhere is severe, unless you want to spend $$$$ on crazy large gauge wire. If I did it again, 48v all the way. 48v to 12v step down to run 12v stuff (like LEDs, HAM radios, etc) are reasonably cheap.
- actual 'solar' batteries are a thing, I'm using them. they're not 'car batteries', they can't do lots of CCAs but they do tolerate discharge and are cheaper for their capacity because they don't have to be vibration/heat/etc resistant like a car/golf cart battery. I want to think mine are 4 years old at this point.
- fuses, fuses everywhere!
- there are multiple angles for the panels depending on the time of year. you can use fixed mounts and use a 'compromise' angle that's good enough half the time. I did this because I built my own panel mounts. I'll pay $150 for a panel but I'm not paying $150 for some bent angle iron to hold it in place, I'm cheap like that. Movible mounts are a thing, but who wants to get on the roof a few times a year and reset panels? auto-moving panels are also a thing, but how complicated do you want this and how often do you want to pay to replace crappy motors? you know that stuff is chinese junk that won't last, or it's going to cost WAY more than it should (see ROI rearing it's head again).

It doesn't cost that much to setup and expernment. I've got enough panel and juice stored up to run the cable modem, router and wifi for 3-4 days 24/7. when the grid is down we're running off the generator but when i shut it down at night we can still do internet stuff on the laptops because the infrastructure is up. it's kinda cool.

Also, my PSA AR is "just as good" as your BCM. :)



(ok, maybe that last part isn't true).
 
Whatever you decide and wanna be efficient with a good amount of AMPs and wattage, go at least 24v with 6v batteries.

price per a watt goes down when you go 6v batteries wired in series then multiple banks for your desired power requirements.

why 6v batteries? Simple, you get higher amp hours per a battery.

why 24 or 48 volts? Less amp draw

solar panels. Well if you’re handy, make your own. Cost for prebuilt panels for anything over 1k watts is expensive.

you’ll save a good amount of you make your own.

I would not invert to AC. If this is a pure off grind ordeal then you can hamd wash and dry your clothes, other ways to heat your house; cooling well, you can invert to that but then your looking at a big set up.

mall this is what I was gonna do for my house for when power was knocked out.

I was gonna run a system that was rated for 10kw (1200w panels, 8 hours light, 9600watts for the day, i was gonna run 24v to start out, then eventually add another 24v as 48v setup is the best). More than what I would have need to run a well pump, a few lights and the fridge, a HAM radio.

if you wanna run heavy load stuff, either add a generator or run those off of shore power
 
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For Heating and Cooling: use shallow geothermal heat transfer, will get you a constant 50 degrees. PVC pipe, either a water loop through a radiator, or direct air heat exchange, generous length, buried 6' deep. It will heat in the winter, cool in the summer.
 
We have a good deal of experience here with Solar. At home we have a 16 KW Outback system installed. It is tied to the Grid and I sell power back when on the grid. This system cost some years ago just north of $100'000.00. I will never live long enough to see any sort of return, nor will it ever pay for itself. The Electric bill here used to run on average $1500 per month. With the main building running roughly $800 of that. Shortly after the system was installed we replaced every light with LEDs, and we did the efficiency hot water system as well. Working to reduce power consumption we got the bill down to between $600-$800 per month. Now I have gotten a bit lazy on the power and it has edged back up to $1000-$1200 per month, but this includes the shooting range as well, which is tied in with the main building. I have been cooling and heating it to a degree as well the last few years. Based on average savings before the solar, LEDs, and other efficiency systems, it would take about 15-20 years to break even.

We installed a rather large battery system, 24 large heavy duty Outback Batteries.

Now, the great thing about this system is that it sends power to the building during a normal day to help run the systems here, it also sends extra to the grid. What little it sends back to the grid is not very substantial, and makes just a bit of difference on the monthly bill. Not enough to get excited about really. First priority of the system is the batteries, then second the power to the building, and third to the grid.

Where the system really pays for itself in my opinion is when we go off grid. Solar panels are not extremely efficient just yet. I have 16kw worth of panels, but on the very best of days in mid June, I can only generate about 13kw. As winter approaches and the sun is further away and at an angle to the panels, then I generate 8-10 kw max.

Going off grid and with decent sunshine, I can run most everything short of heat pumps/air con, clothes dryers, electric ovens and major power consumption units. So, I have to really stay on top of managing the power use here when off grid. Running heat is OUT PERIOD. The heat pumps in winter take a tremendous load. Air Cons, I can run selectively if I am making good power. Ovens and clothes dryers, we don't even attempt that, and can get by without those items. Other than those things we can get by very well, as long as I pay attention to the power consumption.

At night we really have to power down everything. Currently we have 5 big freezers, 2 large refrigerators, 5 small refrigerators. Our goal is to power all of those continuously when off grid, or when the grid is down due to hurricanes and what have you. Those are priority. So we power down things as the sun goes down, so that the batteries can handle the coolers and freezers. We get our consumption down to 1.5-1 kw through the night and the batteries in the morning are normally around 75%. Then we hope for sunshine soon and get those batteries back up.

One of the last hurricanes left us without power for 5-6 days, we managed just fine using mostly the solar system. However, at night, I would kick on the Generator system for a hour or two, so we could keep things cool during the night, run any of the heavy power consumption items needed, and of course to get in a couple of hours of TV! HEH HEH........... The Gen Set here is 40kw, and will run the entire compound.

But believe me, after 5-6 days of power management, which is a damn chore, I was a happy camper when the grid came back on!

The biggest benefit I see for the solar system is that "What If the Zombie Apocalypse Gets Real", and power is down for the duration. It is hard to justify the cost of the system based on selling power back to the grid, and or it paying for itself over time. I could have made better investments most likely with that money, if I was concerned about return on investment. If you are looking to power up things during short term grid outages, it is far better to invest in a generator system, and easier to maintain as well. This system I have is the most advanced solar on the planet, its run by computer, its linked online, we can view the system online and so can Outback. In many cases updates can be downloaded directly to the system, from Outback to keep things running proper. BUT in many damn cases, it has to have some tender loving attention. Its out of most of my area of expertise, and sometimes goes down and has to have expert attention. It is a pain in the ass when it is not running properly. And, not anyone can sort it out. It is terribly and way over complicated. I wish that I had looked into a more simple system at times.

Currently I am only running 1/2 speed, one inverter is down because of a burnt out relay for the fans. $138 part, on order. Also, the area the Inverters are located gets too hot in the summer, so I am having to install a small 12000 BTU Air Con to keep things cool, and the inverters safer, we hope anyway! Solar has its great advantages, but it can also be a major pain in the ass too.........

I can say this, every time we have really needed it when the grid was down for any length of time, it came through and was really great. But I can also say, that in a Zombie Apocalypse, how long would that computer go before it got a glitch? And could I sort that glitch out? I don't know! Ups and downs with everything.
 
We also went off grid with a system at the Farm. It was not as complicated of a system as the Outback is, and was made by Schneider from Germany. Its a small system, 3kw. Well, that POS has been down more than its been run and used! It is such a POS that we are looking to replace it with a small Outback system, not a computer run system. Looking at getting prices now on a 4kw Inverter and battery charge system! Overall, honestly, if you are looking for Solar, go with Outback, its top of the line. I have seen Outback systems in Australia and they run the world in some remote areas of Australia. And, the less complicated the better too I think.
 
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Battery system is 52 volts, when charged they go up to 54-55 and we don’t like them below hi 40s.........I view mostly in percentages, and never let them go below 50%.

LEDs....... there are hundreds of them they vary. For me I go by watts and lumens for my needs. I think I counted once and there were over 400 bulbs on the compound .
 
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