Solar Electric Project

[hayden]

About the only thing I can add is this: your diesel generator can provide a good source of heat as well as electricity

Funny you should mention that - I've been thinking about ways to accomplish just what you describe. My shop/garage is split into two parts. You guessed it, one part is a shop and the other part is garage space. The garage part is uninsulated and unheated, and the shop will be both insulated and heated. The gen set will be in the garage part but will be backed up against the wall dividing the two spaces. The default will be for intake air (combustion and cooling) to be drawn from the open garage space and exhaused through a duct to the outside. The duct will carry only cooling air - the exhaust will go straight outside through some sort of insulated piping.

The options I'm considering involve automatic duct controls that will be controlled by a thermostate in the space to be heated. The options when heat is called for are:

1) Draw intake air from the shop and exhaust waste heat to the shop. This will provide max heating in the shop since it's heating the warm air already in the shop. The down side is that I need to have duct controls on both the intake and exhaust side. There also is risk of fume leakage into my work space which would be dangerous. The danger can be mitigated with monoxide detectors, but there's still risk.

2) I could duct only the exhaust air (but not intake) to the shop. This is simpler ducting since it's on the exhaust side only, but it's less effective heating and when the gen set is cold I'd be blowing cold air into the shop, so I'd have to add another control to only open the duct when there is both a call for heat and the gen set is above some temp.

3) Switch the exhaust duct so it blows into the garage, not the shop. Now my un heated garage would be randomly heated based on gen usage.

Right now I'm leaning towards #1. It's the best solution and isn't a whole lot more work, but I probably won't actually do it until later - I'll just arrange the ducting to the exterior so it can be enhanced later when I have more of an appetite for yet another project.

Actually, as I think about #2 is DOA since exhausting into the shop without also drawing from the shop will pressurize the shop. I'd end up pushing all the hot air out of the space. Bad idea. Strike that option.

 

[tommu56]

Haden
I would look at using the colant you should get more heat out of it.
You would need a coiled for (water) air handler divertor valve and some sort thermostat to control valve when shop would warm up it would divert flow back to original raditor.

tommu

 

[3RRL]

Hayden, great updates and progress on your project.
I have a suggestion for your battery trays if you are have not thought about it yet. You'll need to pull your battery bank out to service the them, I presume. I used light weight furniture movers that hold about 2,000lbs each. Mount a set under/to the tray (upside down) and have a steel angle plate or something for the little rollers to ride on. Your tray will slide out for easy access. You can get them at any hardware store.

 

[hayden]

Rob, thanks for the suggestion. I was very interested in the way you racked your's with the slide out trays and tried to find a way to do something similar. In the end I went with all 12 batteries on the ground in a 6 wide x 2 deep layout. There's only 5 1/2' of headroom in my basement (if you want to call it that) and I decided that going vertical wouldn't provide enough clearance for easy service. I also chickened out on building a rack that would hold nearly 4000 lbs of batteries including 2000 lbs on a slide out tray. And then it would have to be enclosed to provide proper venting.

I went through 4 or 5 different layout configurations for the batteries and for better or worse picked the one I did. At least with all batteries on the ground I don't have to worriy too much about structural integrity. The batteries sit directly on the box floor which is 3/4 plywood, and that sides on 4 2x6 pressure treated boards lying flat as skids on top of crushed stone. I calculated 2 PSI on the stone/skids. The rest of the enclosure serves no structural role, but only provides for protections and containment/venting of charge gases. It's butt-ugly, but hopefully functional.

I should be able to report out in a couple of days on how it works. I hope to get the box and power panel set, conduit run, and batteries in place by mid week.

 

[hayden]

The battery box and power panel are going in my basement. As I mentioned earlier, the house is 200 years old and the foundation is granite blocks laid up dry. I've subsequently mortared up the joints in the walls to keep critters out and to cut down on the drafts, but there is also a center foundation that supports the fireplaces. All the solar equipment will be backed up against this central foundation, but I've never mortared it. I need to now that I won't have access to it after the solar gear is installed.

Here's a picture of the wall all mortared up. Tomorrow I'll haul the battery box down and get it leveled and set in place, then build the power panel.

 

[hayden]

Before setting the battery box in position in the basement and dragging the batteries down, I wanted to be sure my approach to lifting the batteries into the box would work. The approach I'm following is to use an engine hoist to lift the batteries, roll forward, then lower them into the box. The hoist has retracting legs which enables me to get it close enough to the battery box with the lift boom hanging far enough over the box to reach the back row. However, counter weighting is needed to keep the hoist from tipping forward. I wanted to figure out the whole counter weight thing in the comfort of my garage and be sure it would work.

The first picture is of the box in the background and the lift in the foreground.

Next shows the inside of the box with a grid marked off for positioning each battery

Next are the two pallets of batteries covered in the yard

And, so we don't forget this is all about tractors, here are the batteries on the tractor forks on their way into the garage.

The last two show one battery being lifted and lowered into the box. I was able to reach the first row with an 80lb bag of cement on the back of the lift. To reach the second row I had to extend the boom further and with two bags of cement the lift was just balanced. I'll add something else to be sure it's fully counter weighted.

 

[SPIKER]

looking at the pics and reading the posts, I was wondering if you have enough head room to raise up the box higher so the batteries will still clear the top of box when installing/removing them and have the wheels of the engine lift will roll under the box??? may have to play a little slide around to clear the under box supports that raise UP the box but might be safer than the counter weights on the lift?

Nice post I been reading and watching it a while now.!

mark M

 

[hayden]

looking at the pics and reading the posts, I was wondering if you have enough head room to raise up the box higher so the batteries will still clear the top of box when installing/removing them and have the wheels of the engine lift will roll under the box??? may have to play a little slide around to clear the under box supports that raise UP the box but might be safer than the counter weights on the lift?

I wrote you a reply yesterday but fat-fingered it, so here goes again.

I like your thinking, but the problem is just as you suspect. I'm just going to clear the joists as it is now when I load the batteries. Any more height and it wouldn't make it. In fact, I discovered a little oops in my box design and placement related to this. It turns out that there isn't enough height to open the lid completely. I was hoping to have it open fully and park leaning back against the wall. I'm about 6" short on headroom. Darn . Fortunately it opens enough to load the batteries, though for the back row I'll need to lower them most of the way down in the front, then roll back and set them in place. If I need to replace a battery in the back row I'll have to pull the one in front of it first to gain access. If necessary, I'll segment the lid and use a second piano hinge so it opens/folds onto itself.

 

[hayden]

More progress on the solar system. After confirming that the engine lift could get the batteries into my battery box, it was time to start hauling everything to the basement. The first picture is the battery box loaded on the forks, and full of tools and supplies making it's way around the back of the house.

The next show my plank walkway for getting everything in. I just dragged the battery box. At first I tried a dolly, but it was impossible to control and keep on the planks. Dragging worked fine.

The last pictures show the box in place and my power backing panel installed. To mount the panel I used 2x6 pressure treated boards against the granite and used masonry anchors to secure it. Man on man is granite hard stuff. It took forever to drill the 4 holes (3/8") for the anchors even using a hammer drill.

 

[hayden]

Then it was time to start assembling the electronics and get the conduit run between the battery box and wiring panel.

The first picture shows the breaker box. I placed it first so I could get the conduit run between it and the battery box. I had to move the box slightly to get the conduit in, but afterwards everything is in place to stay. The conduit run was critical because the battery cables are only 5 feet long and it's real close getting them to reach so every inch counted.

Then the rest of the gear gets installed. To the left are the two solar charge controllers, and to the right is the 6KW 120/240V inverter. I left the open panel space to the right and will mount the generator start controller and communications gateway there, plus other stuff over time.

 

[hayden]

Finally, time to install the batteries in the box. I had to haul the engine lift around to the basement and bring it in using a hand truck. Here it is in place for the first battery. The plywood (actually OSB) provides a hard smooth surface to roll the lift on.

As a side note, this lift is pneumatic. This sounded great when I bought it and I figured it would make getting the batteries in quicker and easier.

Wrong. What a piece of junk. I can hand pump it much faster than the pneumatic pump. I'm sure glad I didn't pay too much for it.

 

[hayden]

Did I ever mention that the batteries are heavy? I brought the first pallet of them around and this is what happened.

I had to abandon the pallet and plucked the first battery off as a single. They are a real pain to get ahold of. I've been using rope slings under the handles, but the rope stretches and they hang lower that I'd like. It also scares the your-know-what out of me manipulating these things with metal forks. I'm really surprised that the batteries don't come with covers over the terminals. One wrong move and...

 

[hayden]

With something like this, the first one is always the hardest. These batteries were no exception to that rule. I finally got the first one in.

For the next two, I got a junk pallet and walked two batteries from one pallet to the other, then hauled them over to the basement entrance with the tractor. I was then able to walk them off the pallet and on to my hand cart.

At every stage, I used cargo straps to secure the batteries. It would be real ugly if one fell over.

The pictures show two batteries installed in the box, and the third on my junk pallet ready to go in the basement.

 

[hayden]

With only three batteries left on the original pallet, I was able to fork it and bring it over to the basement entrance.

The picture shows one strapped to my hand truck and the remaining two on the pallet.

Then finally, the first six installed in the battery box.

Man does my back hurt

 

[schmism]

how much did you say those weigh each?

i see you have xantrex controler stuff. from my reserch it seems they are the most common for this type of install.

DId you spec out your own system or have some adviser to help pick and choose parts?

 

[hayden]

how much did you say those weigh each?

DId you spec out your own system or have some adviser to help pick and choose parts?

The batteries are 315 lbs each, so a pallet of 6 is about 1900 lbs including the pallet. It's right at the limit of my loader, and even with loaded rear tires I need a counter weight to keep the rear on the ground.

I had been back and forth across that spot several times with loads of planks, plywood, the engine lift, etc. and there were no signs of trouble - at least not until I tried with the batteries.

Yes, the system is Xantrex. I'm trying their new XW line, which looks really good on paper. So far, it's playing out well in reality too. It's very well engineered as a system with all the parts hooking together very nicely. There's way too much Rube Goldberg in the industry, and that has to be fixed to make it mainstream. The XW system is a big step in that direction.

I did the engineering and spec'd out the system myself. It's a bit of a hobby and facination for me. This is the third system I've done, and I'm thinking of starting a business designing and building them. People keep coming out of the woodwork asking me to build them, and that's without trying to find business.

 

[SPIKER]

Hyden:

looks very good:

was wondering about the plastic on the walls? is that for moisture prevention??? I looked into a lot of this about 4+ years back looked at making my barn a solar collector when I had it put up. it has been up 7 yrs now (dang time flies!) I still never got a concrete floor in it or finished it been using it as is... I have still been thinking about getting some collectors up on roof as I designed & staged it to face sun to south. gambrel roof design so I have room for a good number of cells up there. I used to maintain a fleet of electric fork lifts in a full 24/7 production plant. they used batteries that were close to the size of you're bank about 3 times a month one would get cut (cables were 0/4 weld cable) most times only 1 would get sliced into. (inserting & removing from large re-charging rack) which was done by the workers 1~2 times each / day. there were 3 or 4 spots that was major short across the (nearly dead battery's) which would melt out a large hunk of steel! installing charged battery's were once & while bad news for similar reason, (operators not watching the drop leads...)

the weld cable was welded/soldered onto the battery post using small oxy/propane setup! I left that task to the MAIN guy I didn't like having exposed 3000 degree flame on top of a battery that was 3' wide 40" high and 4' long!)


I would have thought that you can remove the acid to make them lighter if need be to move/transport as long as it was only done for short period of time... in case you have to man-handle any on even harder access...


Mark

 

[hayden]

Spiker,

Yes, the plastic is for moisture control. The basement is very damp and we've put plastic against all the granite walls in an attempt to control it. It helps, but is far from a perfect solution.

 

[CATMAN]

Isn't there a need for ventilation for those batteries in that box? Maybe you already have that in your plan.

 

[hayden]

Isn't there a need for ventilation for those batteries in that box? Maybe you already have that in your plan.

Very good observation, Catman! You are absolutely correct.

I have a power vent on it's way to me (along with a couple of other misc items) from the Alternative Energy Store. Once I have it in hand and can figure out exactly where to mount it, pipe it outside, and enter the battery box, I'll hook it all up. The fan is controlled by either the inverter or one of the charge controllers. Both have programmable relays designed for this and other uses. I've also got an external relay coming since the internal relays can't power it directly. I'll then drill some vent holes down low in the box opposite where the power vent exits. I did this in my current battery box, but the venting is all convection. It seems to work fine, but with the bigger batteries and higher charge currents in the new system I want to go with a power vent.