Solar installation

[Rob-D]

Well, I finally got all my panels and inverters hooked up. Took some time because I had to build a structure to hold the panels ( I don't like roof mounts.)
The second photo is the battery box in my basement. I took special care with this. It runs fans off my inverters that kick in when the batteries are charging to remove hydrogen gasses.

The inverters are two Outback VFX3648 pure sine wave. They can run up too 7.2KW and 240 volts to run my well pump. The system is 48 volts. I wanted to run the solar panels at a higher voltage but it gets too cold here in the winter and their open circuit voltage would have exceeded the MPPT's input voltage max.

It's pretty nifty. The system works on the top inverter (the two inverters are in the middle of the photo) When it needs more power the slave inverter kicks in. This saves power. Right now I have it set up to run off the grid if the batteries get below a specific point. This way I always have a good battery reserve if the power goes out here which happens from time to time.
I'm planning on adding a micro-hydro and two home made wind mills and it should run 24/7 with no problems. Right now I have 8-175 watt panels for a total of 1400 watts. With the mills and the hydro it should be over 3,000 watts. Especially in the winter and spring when we get less sunlight but the stream is running well.

So I'm officially off the grid, at least most of the time and it really feels good to be able to shut off the world and notworry about the winter power outages here.

Rob

 

[forgeblast]

Where did you get your inverters from? What brand panels?
The windmill idea sounds great.

 

[Rob-D]

Where did you get your inverters from? What brand panels?
The windmill idea sounds great.

Hi,
Gee, I don't remember off hand as I ordered components over a couple of years and from different suppliers. They are Solar World panels and they appear to be very good. It surprised me because they are rated for 175 watts each and this morning I was getting over 1800 watts out of a system that came in on paper at 1400 watts.

I do have a couple of small Southwest windmills that I can run up but I really want to make my own as well as my own design hydro.
I've been monitoring the wind here on my Davis overthe last coupleof years and it's quite good, the winters here really blow across my front field that's about 4 acres and abuts state land that used to be farm pasture. So I can literally look over a mile of mostly uninterrupted pasture which, as you probably know, is great for wind.

Rob

 

[forgeblast]

how big of a tower are you going to put it in? If you dont mind where are you getting the plans or are you using a book to build the windmill.

 

[Rob-D]

how big of a tower are you going to put it in? If you dont mind where are you getting the plans or are you using a book to build the windmill.

I've been building alternators for years. I go to a large town about 1/2 hour away and get old fields from large hp motors wind the fields, machine the armatures and weld everytyhing together.
The towers will probably be between 30 and 40 feet high. I'm thinking about 1,000 watts each windmill so I can use them the suppliment my heat.

There's are site, if you don't know about it, with lots of info.

Otherpower.com

best,
Rob

 

[sodamo]

Looks nice.
I have those battery miser caps - love em. Use maybe upto 50% less water with them.

 

[LD1]

If you dont mind someone asking, what is your total out of pocket investment to be totally off grid.

I would much like to have a solar or wind setup, but the cost of payback on everything I have looked at is 15-20 years. With my $200/month average electric bill, It would take over 20 years to pay back a 50k system.

A couple of other questions fo you if you dont mind.

1. Why did you choose to go off grid?? Does your electric company do et metering where they will pay YOU if you are making more than you are using?
I know my electric company does NOT. Which is another reason cost of payback is high.

2. How does a totally off grid system handle sudden high loads? For example, working in the shop and running equimpent a lot. Like welders and such???

Good luck with the system and congrats. But until prices come way down, I dont think it's something I am going to be doing anytime soon.

 

[Rob-D]

Looks nice.
I have those battery miser caps - love em. Use maybe upto 50% less water with them.

Thanks David,
Yes, I was surpised to see how little water I have to add.

Rob

 

[Rob-D]

If you dont mind someone asking, what is your total out of pocket investment to be totally off grid.

I would much like to have a solar or wind setup, but the cost of payback on everything I have looked at is 15-20 years. With my $200/month average electric bill, It would take over 20 years to pay back a 50k system.

A couple of other questions fo you if you dont mind.

1. Why did you choose to go off grid?? Does your electric company do et metering where they will pay YOU if you are making more than you are using?
I know my electric company does NOT. Which is another reason cost of payback is high.

2. How does a totally off grid system handle sudden high loads? For example, working in the shop and running equimpent a lot. Like welders and such???

Good luck with the system and congrats. But until prices come way down, I dont think it's something I am going to be doing anytime soon.

Hi LD1,
First, we lose power here often especially when there's a storm, so it's more than just payback but that is important.

I didn't show my panels but they are on my own structure that we built out of treated lumber.
I saved considerably doing the entire install myself, I haven't totaled all the bills yet but it is around 15 or 16k. The good new is that panel prices are dropping and I could have done it for less today as I paid about 900 dollars a panel for 175 watts.

The other thing is that I have a good field for wind AND a stream for microhydro. This will help heat my house when I get the alternators built and in. I expect payback in a few years, maybe five or six if I can get the heat going and that's conservative.
We just found out that our REA (rural electric assoc.) is offering intertie systems at no cost to us so this will tie in too. We get up to 20k of install.

I have welders and lathes too. What I did was set up the electric so the welder is on the grid circuit. So the times I use it it gets powered by the grid although the inverters can handle it pretty well as they can put out 7.2KW plus more for surge.

The battery bank is 48 volts at 560 amps so that's over 13KW (batteries at half power) of power before I have to recharge them.

Here's a partial brake down.
8 panels at 900 $7200
2- Inverters $4000
8 Rolls batteries $1600
MX60 MTTP 500
Power boxes, wire, conduit,
Lugs, screws nuts, etc. $1500
Total=$14,800.00

But I did it all right down to making my own battery cables, digging trenches, constructing the solar panel structure and putting all the boxes and inverters on the panel you see in the picture and then wiring them which took a couple of weeks of work.
I did it over a couple of years, getting stuff and storing it until I had everything to complete the job.

Here's a photo of my office wall. I get all the info about what's going on right from my desk (you can see the Davis weather pro2 in the lower right hand corner)
It's overcast yet the Trimetric is showing that running the house I'm still addingcharge to the batteries (That's the LED 3, showing 3 amps going to charge the batteries)

Rob

 

[Rob-D]

PS:
Here are some of the things I run:

Well pump 240volts
Oil burner motor
oil hot water motor
40 " flat panel TV
Freezer

And of course lighting, the fridge, washing machine and the computer I'm on now.

It's hard to describe the feeling. there's this world out there and we can't see another house from ours and the world is shut off. It's pretty cool actually!

Rob

 

[eepete]

Looks great :thumbsup: ! it's an interesting consideration when you do a project like this and weigh grid tie vs. battery. You can look at the cost of the batteries vs. the cost of a generator. From your cost list, it sure looks to me like the batteries are cheaper than a generator. Jumpers are nice and clean!

I know you saw my solar setup post. I already had a generator, which is part of why the grid tie only was the route I went.

As for the higher peak power, somewhere in all these solar post I had the derating factor for the panels. It goes both ways, so as the weather gets cooler the panels will put out more. Mine were rated at 25 degrees C. Also panels tend to run a bit better than the rated in order to guarantee that they will meet both the initial power spec, and the "10 years later" power spec.

When my automation stuff is done, we'll have to talk....

Pete

 

[Rob-D]

Looks great :thumbsup: ! it's an interesting consideration when you do a project like this and weight grid tie vs. battery. You can look at the cost of the batteries vs. the cost of a generator. From your cost list, it sure looks to me like the batteries are cheaper than a generator. Jumpers are nice and clean!

I know you saw my solar setup post. I already had a generator, which is part of why the grid tie only was the route I went.

As for the higher peak power, somewhere in all these solar post I had the derating factor for the panels. It goes both ways, so as the weather gets cooler the panels will put out more. Mine were rated at 25 degrees C. Also panels tend to run a bit better than the rated in order to guarantee that they will meet both the initial power spec, and the "10 years later" power spec.

When my automation stuff is done, we'll have to talk....

Pete

Thanks Pete,
I do have a 6.8KW diesel Chinese generator but it is not in the system. Boy is it loud! I'll have to work it a bit.
I was thinking about getting a PTO generator but that's down the road.

Shoot me a PM any time you want to chat.

Best,
Rob

 

[BrierPatch]

Thanks for the info and sharing. Good Job ! :thumbsup:

 

[LD1]

Part of my cost of payback figures are that a 175w panel will only produce 65-70KwH per month.

70Kw from the grid is only costing me about $7 per month. So a $900 panel that only saves me $7 per month is not a good investment for me. It would take 128 months to pay for itself privided It lasts that long. And thats not coundting all the other stuff that goes along with it.

I currently am using between 1800 and 2200 Kwh per month. It would require about 30 panels for me to be self sufficent if I went solar only. Thats 27k right there and havent started figuring batteries, controlers, inverter, etc.

I think the stuff is going to have to get WAY cheaper before I jump on board.

But I also have affordable and reliable power. In 5 years, I have only had one major outage and that only lasted 4 hrs when remenats of hurricane Ike (i think) cane through last september.

 

[Rob-D]

Part of my cost of payback figures are that a 175w panel will only produce 65-70KwH per month.

70Kw from the grid is only costing me about $7 per month. So a $900 panel that only saves me $7 per month is not a good investment for me. It would take 128 months to pay for itself privided It lasts that long. And thats not coundting all the other stuff that goes along with it.

I currently am using between 1800 and 2200 Kwh per month. It would require about 30 panels for me to be self sufficent if I went solar only. Thats 27k right there and havent started figuring batteries, controlers, inverter, etc.

I think the stuff is going to have to get WAY cheaper before I jump on board.

But I also have affordable and reliable power. In 5 years, I have only had one major outage and that only lasted 4 hrs when remenats of hurricane Ike (i think) cane through last september.

LD1,
I understand your perspective.
The only thing I see is that 1400 watts of power (really about 1600 to 1800) on a sunny day will give me, in an 8 hour day, 1.4 x 8 or 11.2 KW a day. Lets say there are 21 days in the month that are sunny. That gives me 21 x 11.2 or about 235 KWH, not 70. Also we do all our heavy work during the day, cloths washing, etc. If I get an electric car that gets charged during the day too. The other thing is that I have cheap power here. Yes , I have to make my own alternators and windmills but I'm retired so the time is mine. I can make a windmill in about 3 or 4 days and a hydro alternator in about 1 or 2. Now add that and I'm way ahead.

Rob

 

[LD1]

LD1,
I understand your perspective.
The only thing I see is that 1400 watts of power (really about 1600 to 1800) on a sunny day will give me, in an 8 hour day, 1.4 x 8 or 11.2 KW a day. Lets say there are 21 days in the month that are sunny. That gives me 21 x 11.2 or about 235 KWH, not 70.
Rob

The 70kwh I was refering to was for ONE 175w panel in a month. .175 x 12hrs a day x 30 days =63. I was being optimistic as well. This would be an absolute best case scenerio.

So 1 pannel that cost $900 will make "at best" 63 kw per month. 10cents per kwh current rate, that is $6.3 per month saved.

My current electric usage is around 2000kwh a month. 2000/63=~31 pannels I would need.

 

[Rob-D]

The 70kwh I was refering to was for ONE 175w panel in a month. .175 x 12hrs a day x 30 days =63. I was being optimistic as well. This would be an absolute best case scenerio.

So 1 pannel that cost $900 will make "at best" 63 kw per month. 10cents per kwh current rate, that is $6.3 per month saved.

My current electric usage is around 2000kwh a month. 2000/63=~31 pannels I would need.

Thanks for the clarification, as you can see I was going on the low side.
2,000 KW a month, that's a lot.
My thinking is that part of going off grid is cutting usage too. WE store grains and I've shut down the freezers and vacuum packed our grains for long term storage.
We use a high speed spin dryer and clothes racks. The high speed dryer removes so much soap and water that the clothes dry in 20 minutes to an hour or so.
Our stove is now gas and we use oil heat and hot water but I want to build a solar hot water supplemental heater also.
Electric is used at a minimum here. Sure when I turn on the MIG but even that isn't bad for the length of time I use it. Even my lathes are low HP.
I'd say I'll be under 600 KWH in a month and probably well under 450 when I'm done.
So our electric runs the furnace motor (radiant floor heat that's very efficient) and the oil hot water right now but I built a small house so we don't go through a lot of fuel even in our cold winters here. Also the house is designed to maximize the elements with a sun room on the south side that adds warmth to the house if the temperature gets up to 30 or 40F and it's a sunny day. In the summer maple trees shade it. I also have areas of the house that I can shut down and a north side pantry that stays cool for food storage.
We also have a soap stone Tulikivi fire place with a bake oven that stays warm for about 12 or 14 hours after the fire goes out.
Of course all our lamps are CFL or LED.

Rob

 

[LD1]

Thanks for the clarification, as you can see I was going on the low side.
2,000 KW a month, that's a lot.
My thinking is that part of going off grid is cutting usage too. WE store grains and I've shut down the freezers and vacuum packed our grains for long term storage.
We use a high speed spin dryer and clothes racks. The high speed dryer removes so much soap and water that the clothes dry in 20 minutes to an hour or so.
Our stove is now gas and we use oil heat and hot water but I want to build a solar hot water supplemental heater also.
Electric is used at a minimum here. Sure when I turn on the MIG but even that isn't bad for the length of time I use it. Even my lathes are low HP.
I'd say I'll be under 600 KWH in a month and probably well under 450 when I'm done.
So our electric runs the furnace motor (radiant floor heat that's very efficient) and the oil hot water right now but I built a small house so we don't go through a lot of fuel even in our cold winters here. Also the house is designed to maximize the elements with a sun room on the south side that adds warmth to the house if the temperature gets up to 30 or 40F and it's a sunny day. In the summer maple trees shade it. I also have areas of the house that I can shut down and a north side pantry that stays cool for food storage.
We also have a soap stone Tulikivi fire place with a bake oven that stays warm for about 12 or 14 hours after the fire goes out.
Of course all our lamps are CFL or LED.

Rob

Wow, I wish I could get by with only using 600kwh a month.

Right now my biggest two users are the heat pump and hot water heater. It is a marathon and very efficcient but still uses a good bit of electric.

My lowest usage ever was about 800kwh. That was when I first moved in and it was one of them months that stayed about 70 degrees in the day and 60 at night so no AC use or heat. And of course that was before the 30x50 garage that I am always in now and before the goldfish pond with a 250w pump and before the two motion detector halogen lights that total 5 150w bulbs. It all adds up.

But even if I could cut my usage, the COP would still be the same, (actually a little more because rates are lower the more you use). But regardless of usage, a $900 panel will still only save at best $7 a month.

I will probabally never invest in alternative energy until my local coop will no net metering. The main reason is because I still want to be grid tied and not have to worry about batteries and such. And when I am not at home, and demand is low and I am still producing power, I can sell back to the power company.

My ultimate longterm goal is to actually get a check from the coop every month. I wont jump in with both feet, just start small and add to the system as money allows until I can produce more than I use. But again, they will have to start doing net metering first. And the cost of alternative energy has to come down a bunch. Like a 5 year COP before I would be interested.

But I am really interested in your windmills and waterwheels. You said you were using alternators. If you dont mind, could you share some details. Like what type of alternators to look for? Are you using one wire alternators. Of are you using ones with seperate regulators? How are you energizing the field windings? How much power are they actually making you?

I have pleany of access to old car parts for free (I am a hoarder) and I enjoy building/fabricating things. I have been wanting to expirement around with this sort of thing, but since you have already done it, I figured I'd ask you what you have found to work the best.

 

[jinjimbob]

Wow, I wish I could get by with only using 600kwh a month.

Right now my biggest two users are the heat pump and hot water heater. It is a marathon and very efficcient but still uses a good bit of electric.

Have you looked into a heat pump water heater? They're pretty easy to install, just a swap out, the only new thing needed is a drain line.

I'm all electric at our house, used 1100 last month, heat pump and water heat pump.

 

[Rob-D]

Wow, I wish I could get by with only using 600kwh a month.

Right now my biggest two users are the heat pump and hot water heater. It is a marathon and very efficcient but still uses a good bit of electric.

My lowest usage ever was about 800kwh. That was when I first moved in and it was one of them months that stayed about 70 degrees in the day and 60 at night so no AC use or heat. And of course that was before the 30x50 garage that I am always in now and before the goldfish pond with a 250w pump and before the two motion detector halogen lights that total 5 150w bulbs. It all adds up.

But even if I could cut my usage, the COP would still be the same, (actually a little more because rates are lower the more you use). But regardless of usage, a $900 panel will still only save at best $7 a month.

I will probabally never invest in alternative energy until my local coop will no net metering. The main reason is because I still want to be grid tied and not have to worry about batteries and such. And when I am not at home, and demand is low and I am still producing power, I can sell back to the power company.

My ultimate longterm goal is to actually get a check from the coop every month. I wont jump in with both feet, just start small and add to the system as money allows until I can produce more than I use. But again, they will have to start doing net metering first. And the cost of alternative energy has to come down a bunch. Like a 5 year COP before I would be interested.

But I am really interested in your windmills and waterwheels. You said you were using alternators. If you dont mind, could you share some details. Like what type of alternators to look for? Are you using one wire alternators. Of are you using ones with seperate regulators? How are you energizing the field windings? How much power are they actually making you?

I have pleany of access to old car parts for free (I am a hoarder) and I enjoy building/fabricating things. I have been wanting to expirement around with this sort of thing, but since you have already done it, I figured I'd ask you what you have found to work the best.

LD1,
I just opened my co-op bill before I read your post. Right now I'm under 580 KWh a month but even my auto-trip outside lights are CFLs.

What I will do is start a projects thread with pictures when I do the alterntors.
I run NdFeB magnets in the armature and wind or rewind, the 3ph alternator to give me a specific power at a specific rpm. I have a collection of enameled wire so i can contour the alternator just the way i want it. If you have a lathe or access to one, you can do most of the work.

I run the output voltages higher than my batteries when the alternator is running at speed and just use diodes (schottky for a low forward voltage drop). My MPPT regulates the power for battery charging so even if the voltage varies it still goes to the batteries as a charge just as long as i keep it above the battery voltage itself.

You can PM me if you have any in depth questions.

Rob