Update 8-11-2024 – the upgraded off electrical grid system has been operating for a few weeks now with no problem. I can run my air conditioner all day, shop tools, air filters, lights and everything else. However I still use a lot of direct solar electric power, bypassing the batteries, inverter and charge controller wherever possible.
1. Updates on this project will also be posted to my YouTube channel – the most recent video is posted below
2. Older videos are posted at the bottom of this page.
Running my workshop with off electrical grid power has been a goal for some time. But batteries are expensive! Until recently, all I had was a few small Solar Generators and very small batteries available for the purpose. The 1200w+ of solar panels out front would mostly run heating loads in the winter. Smaller 100w solar panels provided lighting and ran other small equipment. 18v power tool batteries do a lot of the work too.
Planned Upgrades for the Solar Workshop
Energy Storage
The greatest priority is to upgrade the energy storage capacity. Due to the presence of freezers and other critical loads, my main property (residence) already received a good sized LiFePo4 off grid system. Food is more important than the workshop. So the Workshop always missed out on upgrades. That’s about to change.
Phase 1
The shop gets pretty hot in the summer. First task is to run a 5000btu window air conditioner non-stop all day from batteries and solar. Plus a computer used for video work, using about 150w of power. And a dust collection filter for shop work. Current battery storage only supports a couple of hours operation per day, which is not enough.
I have received a shipment of LiFePo4 batteries (standard group size). These are installed in the workshop as a permanent off electrical grid power system. With this system I will be able to power my Air Conditioner all day long, even after sundown.
The batteries being installed are 6x 12V 100 AH (amp hour) LiFePo4 drop-in style which will be placed in parallel. Total theoretical energy storage is about 7 kW/h (kilo-watts for an hour).
Phase 2
This is going to be huge – I am waiting for a large shipment of prismatic LiFePo4 cells which will be hand built into a good size battery bank. Hopefully I will be able to record the process on video and share my over 10 years of experience and methodology in hand building LiFePo4 battery banks. Please stay tuned for those updates.
Charge Controller
The first charge controller to be deployed in the workshop is a 60A MakeSkyBlue MPPT unit. It’s a very compact, affordable and straightforward design. It will be enough to run the air conditioning all day until the charging system gets expanded. The charge controller is being bench tested right now along with a new inverter.
Later I will increase charging and solar panel capacity, to allow for running 2 air conditioners and more heating in the winter.
Inverter
A couple of weeks ago, I purchased the 12v Ampinvt 1200w LF (low frequency) pure sine wave inverter due to its attractive price. I opened the inverter and found its build quality to be pretty good. With a large toroidal transformer, this inverter does not struggle with small inductive loads such as a the window air conditioner located in my shop window.
This inverter will be installed on a solar power equipment board in the workshop with decent sized copper cables and and ANL fuse block.
At some point a larger inverter will be added to run a miter saw and other more powerful shop appliances and machines.
Current status and updates
This work is ongoing. So far I have the inverter, circuit breaker, fuse, charge controller, cables. The standard group size LiFePo4 batteries are installed and cabling is being completed. The power board itself has already been built. I am in the process of cleaning up the many wires and cables that have been draped all over the workshop to support various work and research projects.
I will post related content and updates below as they are developed.
Solar Workshop Updates, Links, Videos
Part 1 work late June 2024: Video posted on this page. I will add more videos here ASAP. Work includes solar powered workbench lighting, building a solar power equipment board for the work bench, connection of direct DC solar power to workbench, cable and wire management and a few other updates thrown in.
Part 2 work late June 2024: I installed a 1200w pure sine wave low frequency inverter with WattCycle batteries, a MakeSkyBlue charge controller and some other gear to support it. The inverter is easily able to run my air conditioner all day, especially with 1200w of solar panels.
Solar Thoughts blog 