Boilermakers DIY Solar Journey

[blrmaker]

After reading the “who has gone solar” thread, I have decided to share my journey of building a complete solar hybrid system for our shop and then the new home.

First of all, I am not an electrician, nor do I play one on TV. I do not recommend installing anything you are not completely familiar with. I have spent so much of my gray matter working the system out, I have none left for the remainder of the house. My county does not have a building department so no permits were required however I made sure to follow the NEC rules as best as I could. A big shout out to www.diysolarforum.com for the huge amounts of information I was able to garner and guidance. Ultimately though I have had my AC electric work inspected by my contracted electricians and my local utility with full approval.

This area of Texas has a grid that can be affected by weather and is less than reliable so when we were planning the new house, I made sure to start looking into something more reliable. We originally purchased our land to be more central between our children and grandchildren moving from Tennessee. We have lived in our camper on site since selling in Tennessee while we have worked with the architect to finalize plans. During these couple of years, we have been without electricity for up to a week at a time. The ultimate goal when complete is for our home to be as energy independent as possible.

 

[blrmaker]

I was watching a guy on Youtube named Will Prowse who installed a kit solar set up and made it look simple. I ordered one of the kits for our shop to learn on and it is rather fun planning, executing, and then the rewards when it actually worked out.

Signature Solar is a local supplier that is DIY friendly. One important factor to me is a brick-and-mortar place where I can talk to real people face to face. They have opened a new showroom since I have started purchasing from them and I have to say it is pretty fancy. Most of my equipment was sourced through Signature Solar excluding the racking. The PV racking I source through online vendors.

We ended up with a solar bundle kit with 2@EG4 6500 inverters, 24 Solever 455W PV panels, 4@EG4 Batteries, 1@EG4 battery enclosure, 2@ IMO PV disconnects, and not nearly enough cable. The kit did not come with racking, battery buss bars, or circuit breakers.


Battery enclosure was easy to put together but a beast to get each battery on its respective shelf. HEAVY!

 

[blrmaker]

This will be a slow thread as I am only home to continue one weekend every couple of months and the house is not complete.

 

[budman]

I will read slowly....... but look forward to it.

Looks like a good size piece of land. Wondering what the two blue dotted areas at the back represent?

 

[blrmaker]

I will read slowly....... but look forward to it.

Looks like a good size piece of land. Wondering what the two blue dotted areas at the back represent?

Next summer I will fence and cross fence that area. Then have some of it cleared for 3 cows.

 

[auntiebling]

oh this is cool thanks for sharing!

 

[blrmaker]

This whole process started 2 winters ago. The batteries were fun getting into the cabinet. I needed to add a framed wall near my load center in the shop to mount the inverters. So I framed a wall, then added 1/2" plywood which was covered by 1/2" cement board for a small level of fire proofing. The inverter spacing was not ideal since I believe they needed 7" between for cooling. They ended up pretty close to the breaker box.

The inverters are completely off grid so there is no AC input to them. There will only be PV input, battery input, and AC out to feed that breaker box.

 

[Grissom]

Looking forward to this thread and thanks for linking the solar forum

 

[mercurial]

Putting it on the ground makes everything so much easier and more approachable. You can take your time getting it done, and do it exactly how you want. Should be a fun project.

Like all home improvement, you will hate the project once you are half way into it lol

 

[blrmaker]

Here is the example I was using from Will Prowse. The ac input to the load center is via a 60 amp 2 pole breaker on the load buss bar. The inverters each feed one leg of the buss bar with 120V which allows for running 240V loads.

Our shop loads are as follows:
240V hot water heater
120V window unit air conditioner
2@120V refrigerators
1@120V stand up freezer
1@240 stove/oven
1@120V washing machine
1@240V dryer
1@50Amp RV service
Normal 120V outlets and lights

The 50A service runs our camper. The camper loads:
2@air conditioners
1 hot water heater
1 refrigerator
Normal lights and appliances.

 

[blrmaker]

I installed the battery buss bars and a set of DC breakers. I don't remember why I went with the breakers rather than the T class fuses but it was probably to have the DC disconnect. The grey com wires allow one inverter to be the "master" and the other to follow directions. Both inverters have wifi connection but I was never able to get the second one connected. When they are running there is an app "WatchPower" for monitoring. Unfortunately when only one inverter is reporting, I am only logging 1/2 of the information.

 

[Bubba_s]

Subscribed!

 

[blrmaker]

Installing the supplied PV disconnects. I later changed to DC breakers rather than the IMO rotary switch. I believe that was a mistake. There are many reported instances of the breakers catching fire when they were switched under load. The IMO switches I believe are better designed to break high voltage DC but the best practice is to not switch the DC under a load if possible.

 

[blrmaker]

All wired up. You can see the PV breakers instead of the previous pic with the rotary switches. Once life calms down a bit I will change the breakers back to the switches.

The inverters have 2 MPPT inputs each of 500Vdc @ 18A. Time to start installing the PV racking.

 

[blrmaker]

The shop is metal so I was looking for a specific type of attachment for the racking. I found Snap-N-Rack made a metal roof mount that looked promising. Their website also has a configuring page which allows for your total rack, does the calculations, produces a bill of materials, and even has some of the engineering data for your local permitting submission. I decided to go with the entire Snap-N-Rack system which worked flawlessly. My biggest problem was the configure spread sheet did not anticipate (neither did I) that my roof was not on 24" rafters but horizontal purlins. I ended up bridging vertically between the mounts in this picture with Unistrut then running horizontal with the Snap-N-Rack rails.

 

[blrmaker]

Once the roof mounts were laid out, squared and secured, the Unistrut started going on. The Unistrut and associated extra stainless hardware increased the price of the racking by a couple hundred dollars. Once the Snap-N-Rack "L Foot" mounts were attached the rails just click into place. Nice design.

 

[blrmaker]

Racking installed. Before installing the solar panels, it is important to inspect the panels for which side is positive vs negative. These panels are 51 pounds apiece and I did not want to handle them more than needed, especially on the roof.

 

[blrmaker]

Here is a crude drawing that I used for determining which way each panel went up. My plan was to split the 24 panels into 4 strings of 6 with no paralleling. The Solarever 455W panels have a open circuit voltage of 49.35V with 11.44 short-circuit current (Isc). When you combine 6 panels in series the volts add up but the amps do not. The inverter can accept up to 500V@18A per MPPT so each string needs to be below that. Each string will theoretically produce 296.1V at 11.44A. They will never actually produce that but I used those figures to give me a safety cushion.

One crazy note is that PV panels are more efficient the cooler their temperature. The voltage will go up when the temperature falls. I ended up using an online calculator by Midnight Solar to make sure my panels would not exceed the inverter inputs when the temperatures drop.

 

[blrmaker]

These panels were too heavy to bring up a ladder by my self so I used the mechanical means I had available.

 

[blrmaker]

Array is finally complete. PV wiring in progress.