A Sol-Ark Grid-Tie Install with Battery Backup
Hello. My name is Jeff Poole and I’m in my ninth year at Backwoods Solar, supporting solar enthusiasts like you in the pursuit of energy independence. My pursuit began in 2014 when my family and I began building a house just outside of Sandpoint, Idaho. Our homesite was at the end of the line for two separate local utilities in our area, one electing to provide service for a hook-up fee, monthly membership fee and usage fees. The cost to install an off-grid system sized appropriately for the family’s usage was much higher than a grid hook-up. At the time we simply could not justify the additional expense and hoped that the day would come when we could install a solar electric system. Upon becoming a member of the Backwoods Solar team, I was eager for the opportunity to install a grid-tied critical load back-up system as soon as possible.
Cut to 2022, and it’s time to finally build our garage. We designed the garage to carry the solar array on a shed roof and created a space inside for equipment. With the help of my Backwoods colleagues, I created a custom system design centered around a Sol-Ark 12K all-in-one inverter/charger that would back up my critical loads with about 4 days of autonomy from a 400Ah lithium battery bank from Eclipse Battery. I contracted a local installer, Zach Betz of Independent Electrical Solutions, to provide the installation, which was done in stages throughout the summer of 2023. We pulled electrical permits and Zach’s crew began with the install of UL listed adjustable roof mounted racking from Tamarack Solar Products and 5kW of REC Peak 72 solar modules. The array includes a rapid shutdown system from AP Systems to meet electrical code requirements. Once the garage interior was ready, the Sol-Ark went up on the wall with the critical load panel and garage sub-panel (see picture below). One benefit of the Sol-Ark design is the ease of installation; the unit includes an inverter/charger, 2 MPPT trackers, and an integrated power panel with disconnect breakers for battery, generator, grid and loads. Having fewer components to mount and wire really saves on install time and expense and makes for a clean install.
Once installation was complete, it was time to commission the system. Bringing a Sol-Ark online is a very straightforward process and our system fired up and was programmed with basic parameters within 15 minutes. Sol-Ark’s web-based interface and mobile apps make programming and monitoring a breeze. This system was programmed to not sell back to the grid but to provide pass-through power to the entire house. Any solar energy harvested goes straight to loads while keeping the batteries in a float state for use when grid power fails. Upon a grid failure we have the ability to provide power to just the critical load panel or to the whole house, in case another “non-critical” load is needed. The critical load panel is set to keep refrigeration, radiant floor heat, fresh water, a few power outlets and a some LED lights available for up to 4 days. Battery protection is set to prevent the battery bank from over-discharge. When solar is not available during an outage, a generator input will keep the battery bank charged.
Our system has been in place now for 6 months and we could not be happier with our design. The Sol-Ark has several modes of operation for use in off-grid or grid-tied installs. Grid-tied installs have the choice of selling excess energy back to the grid (with a bi-directional meter) or just using the power for the home. The Sol-Ark has numerous features for load shaving, time of use, grid-limiting, and the ability to perform well with a variety of battery chemistries. So far, I have just one complaint. There seems to be no notification sent when grid power goes out. A notice that grid power has returned is sent, which seems odd. I have contacted Sol-Ark about this and been informed that an upcoming software update could contain this notification; we’ll await that feature for now. Besides that, I am impressed with the build quality, the ease of installation, programming and maintenance, the ability to power our whole house, the useful web interface and mobile apps, and the small install footprint. And Sol-Ark’s customer service continues to receive the highest marks from Sol-Ark users. Our power is much more stable and we have the peace of mind that our home is backed up during an emergency, keeping our growing family safe and secure. If you are considering an off-grid or grid-tied battery back-up system for your family’s energy independence, I heartily recommend a system that includes a Sol-Ark
A Sol-Ark Install Update: Adding a Second Inverter
Above, I shared my grid-tied Sol-Ark solar electric system installation experience with you. Now I’d like to give a first-hand report on upgrading the current system to include another Sol-Ark 12K in parallel and a battery swap to Midnite Power’s new PowerFlo16 heated lithium-iron batteries. These changes were made to provide more energy to power more loads, additional battery bank capacity for longer run-times during low solar production or utility outages, and heated batteries to avoid battery damage when temps drop below freezing. Read along as I relate how easy it can be to scale up solar electric systems with help from Backwoods Solar.
In my earlier article I noted the intention of the original system design was to offset some utility charges and have critical load back-up power during a utility outage. The initial system provided both to a modest degree and performed as expected with very few issues or faults. However, when household energy usage was reviewed, it was thought that increased available energy would make the system more responsive and reliable by splitting the loads between the two parallel inverters.
Another concern when using the system was keeping the original Eclipse lithium-iron batteries warm enough during cold winter months. Lithium-iron batteries can be damaged when used in temperatures below freezing. The system is housed in a detached garage that is well insulated but can drop below freezing in cold snaps. By installing Midnite Power PowerFlo16 batteries with built-in heating, low temperature concerns are no longer an issue.
The actual installation went smoothly but for one breaker whose legs I reversed inadvertently. (Always double check your wiring!) Once the slave inverter was on the wall and connected to the internet I contacted Sol-Ark to update the firmware on both inverters, which is required for parallel use. This process took about 15 minutes for each inverter and required a restart. Then, with the batteries in place and the wiring installed and confirmed, the system was placed in parallel mode with the battery bank in open loop communication. The system was then restarted, slave first, then master. After going through the start-up cycle the system master inverter recognized the slave inverter and both operated as expected in “Limited Power to Home” mode. In this mode energy from solar, battery and the grid provide power to the critical load backup panel. When extra energy is available other non-critical loads can be covered as well. This system allows for load shaving, time of use, grid-limiting, and performs well using a variety of battery chemistries.
This is all to say that updating or expanding a solar electric system can be done with a minimum of effort when using the experience and guidance of the Backwoods Solar team. We have the components you need and the finest (and free) support to help you tackle any project. If you are considering changes to a current system or need to install a new off-grid or grid-tied solar electric system give Backwoods Solar a call to find out how we can help you achieve your energy independence.