busbars pictured above at all times. The safety mats are removed here to show some detail of this build.
COMPONENTS
One 130 Watt Solar Panel
One Morningstar ProStar Solar Charge Controller / $212
Four Trojan T105 6V batteries / 447 Amp Hr / $115 each / wired in series and parallel providing a 12V system with 894 Amp Hr capacity. Purchased from local golf cart company who could answer all my "best battery for application" questions.
One DC to AC 5K24012W Inverter for 220/440 electrical well pump / which I broke in the learning curve and it cost me to learn the weakness of my design. Could not blame this on someone else or find a safe place to make me feel better. Just ate it! More on this below.
One AIMS DC to AC 1500 W Inverter. Works perfectly!!
One car charger outlet for direct 12V applications.
Built the cart and busbar from pieces gathered in the shop and from purchased items.
.......................................................................................
From the top.
If you are inclined to build a solar project, do your own homework. Do not use this blog as your guide to build, but rather as an interesting read and maybe an opportunity to learn.
AC voltage current is "alternating current". Because the current is constantly stopping and changing direction (alternating) it can be "let go of" if a user gets shocked (low household current 120V for example).
DC voltage current is "direct", one direction, current and is always "on." A user accidentally grabbing a DC current line cannot let go: thus, the notice here is to pay attention. DO NOT BELIEVE A 12V SHOCK IS NOT SOMETHING TO WORRY ABOUT. IT IS AND IT CAN KILL YOU.
AGAIN---DO YOUR HOMEWORK IF YOU ARE GOING TO BE HANDS-ON WORKING WITH ELECTRICITY. "HEY"!! EYE CONTACT HERE!!! DO YOUR HOMEWORK!!!!
The above listed components were my choice from many options.
The cart was designed around the component dimensions and space needs.
The aluminum busbars (positive and negative battery electrical connections) - the middle photo - is always covered with a safety rubber mat. The mat is removed here for visual aid.
The batteries and connections are also always covered by the white perforated removable shelf. The shelf serves as a temporary storage area as well as safety cover. I wanted to make sure that no accidental dropping of tools or mis-touching would ever result in electrical shock.
TOP PHOTO
Three-wheeled cart for easy movement around the driveway and property. Always stored in the garage. Solar panel pivots to access seasonal sun alignment. The cart is simply turned during the day to follow direct sun as wanted.
MIDDLE PHOTO
Shows battery storage, electrical hook up to the BusBar, 1500 W inverter installation and perforated shelf for safety, ventilation and temporary storage. Laptop is plugged into 12V outlet for a test charge that day. The busbar is uncovered for this photo. A non-conduction rubber mat completely covers the busbar otherwise. (repeating my-self)
LOWER PHOTO
Shows the solar charge controller at work indicating a 7.6Amp charge at the moment the photo was taken. The max charge I have seen in perfect bright sun is a charge of 8.2 Amps per hour.
..........................................................................
THE QUICK VERSION
I wanted to build my own solar generator. I wanted the education and to learn what I could accomplish. The project lasted two years due to piecing parts together that would build a solar generator that would ultimately run our 220/440 Volt well water pump.
A major design parameter for this generator was to run the water pump for 15 minutes or so at a minimum. I could then recharge from the sun and do it again. Fifteen minutes of pumping water would yield about 70 gallons of fresh water that could be stored.
A major design parameter for this generator was to run the water pump for 15 minutes or so at a minimum. I could then recharge from the sun and do it again. Fifteen minutes of pumping water would yield about 70 gallons of fresh water that could be stored.
The additional smaller 1500 Watt inverter and a direct 12V connection option would complete the major design components.
I was new to most all of this. I did understand and respect working with electricity and direct current. Hell, any current!! I knew series vs parallel wiring. When volts add up and amps add up through wire connections. I could wire a system from a good drawing. I took my drawings to several folks with experience in the electrical fields to confirm that part of the design and to also seek additional information I may be over looking.
If I went to one Solar store, I went to dozens asking questions. Many would give me hand outs for the starting $12,000 home installed system. Hand outs for computing all the items I intended to run from the system; OR, often the little out of the way Solar Store was closed; OR "the guy" I needed to really talk to was not in that today, OR they had a pre-built solar generator I could purchase. I never ever found "the guy" until I broke the expensive inverter that was to run the well water pump.
The 12 volt system I designed and built was great for a 12V system for smaller needs. But there was not enough power in my design to run the large inverter and when I turned on the bigger inverter, it fried itself internally.
The 12 volt system I designed and built was great for a 12V system for smaller needs. But there was not enough power in my design to run the large inverter and when I turned on the bigger inverter, it fried itself internally.
I finally found "the guy" by accident. I found that I was looking for building a solar generator help from the wrong folks / wrong stores. "The guy" was a fellow who worked on, designed and maintained large off grid home solar applications. Just a guy who drove an older car, came to the garage here with pen, pad and a volt meter in hand. I learned more in one hour with him, than I did in the two years building the generator. Simply put, I should have designed a 24 Volt or a preferably a 48 Volt system. Through drawings, math and volt meter readings he explained all of this to me. I understood, but in no way can relay that to you then or now. I would not even try.
The 12 Volt system was not big enough to handle the power needs of the large pump at the bottom of our well and the inverter I had planned to use.
The 12 Volt system was not big enough to handle the power needs of the large pump at the bottom of our well and the inverter I had planned to use.
"The guy" charged me an hours labor for his time and my education. The very cheapest cost associated with this whole project. He left, and I sat in my chair and looked at my generator (top photo) for the longest time. It is pretty, does work quite well for a 12V system and will provide in a temporary or all out electrical emergency. But it will not run the well water pump.
The direct sun will bring the batteries to full charge in a few hours and that is always fun to see the lost capacity return to 100% from the power of the sun.
I can charge a trove of Ryobi batteries and run a myriad of lights and hand tools using this system. It will charge cell phones, lap tops and run a ham base station. Can run strings of 12 volt lights, outdoor lights, recharge car batteries and other similar electrical use/needs. I can cook a full slow cooker meal when the generator is charging in the direct sun.
I have learned so much more about volts, watts, amps, batteries, solar and how very cool it is that the light from the sun can provide electricity in the design and building of this project
It is not like plugging into the grid, and it is not like never, ever having electricity again in the after.
It is not like plugging into the grid, and it is not like never, ever having electricity again in the after.
I did finally find a store and fellow in Manchester, NH who helped me put the above pieces together in design. Answered most every question I knew how to ask. I paid a little more purchasing parts from him, but I could take them back if they did not work out of the box. They were not damaged in shipping. I could not do that with off the net ordered items.
Besides, I am a person who likes human contact and to touch things I plan to purchase. Especially important bigger items. That has value to me and I am/was willing to pay for it. I have learned it is quite often cheaper in the long run.
Advice to you if you want to build a solar generator.
- Have a good idea of what you want to run and ask a lot of questions.
- Practice safe procedures always throughout the build and then in daily use.
- This not a tool for anyone to play with or to try to operate. Never let children have hands' on opportunities with your home-built solar generator. Never let others use the generator unless you have taught them and trust them. Never let anyone borrow it.
- Know it is going to cost you and do not cut corners. Buy quality.
- Find "the guy" early on in your design and build. If he/she is not interested in you and your project, move on till you find "the guy." Look for the guy who designs, builds and maintains in-home off the grid systems. Ask off-grid home owners who helps/helped them design and solves problems.
- Pay for some of "the guy's" time in design and inspection from work completed.
I found a clamp meter for measuring current to be an affordable and useful tool when trying to figure out what else I could run off this system and for how long. I had to split a small extension cord so as to take an amp use measurement.
I first used this to figure out how many amp hours the slow-cooker ran at to help me figure out how that I might best use a slow-cooker with this generator. The slow-cooker uses around 6 amps per hour if memory serves me right and was best used while the generator was in full sun light. The power from the solar panel was just a little over what the cooker needed. Very little energy was needed from the batteries. I can cook a meal in direct sun light for 6 hours with little challenge to the system. A large pot of soup/stew for a family dinner cooked using solar power was also an eye opener for me.
Coffee is an important part of our mornings. This solar generator will run a morning coffee pot. How about your electric razor? Yep!!
Another item to consider is a 12V water pump. Maybe pumping filtered water or using an outdoor shower. Regardless, building your own solar generator can be designed to fit your specific needs or wants.
The generator is several years old now and I am still learning. It is safe to be around and to use. This was a very important part of design and concern. I over emphasize this here in this week's blog because safety in working with electricity in a project like this is job one.
Making a little electricity for yourself could be of great benefit in the after. In the meantime, some new skill sets are acquired.
................................................................................
Always heads up! Have a wonderful week. 
