Victron-Pylontech System Powers Off-Grid Mountain Home

With kids out of college and retirement a few years away, Rich and Julie started making bold moves toward their long-term plan: living full-time in Montana. After several years of looking, they discovered and purchased an isolated property with a 360-degree mountaintop view on a dirt road just wide enough for an ATV. “We both laid awake all night in the hotel afterward, thinking, ‘What did we just do!?’ says Julie, laughing. 

They were starting from scratch: no water well, power source, and no structures on the 20-acre property. “First, we looked at bringing in a power line because, ironically, there's a major power hub just a half mile away. It was just going to be incredibly expensive to get it here.”

After receiving a quote for 60K, the couple did the math: “We would be spending 60K to bring in power and would pay a utility bill every month for the rest of our lives. Even so, we would still need to buy a backup generator in the event of a power outage—another big expense. At that point, we started looking seriously at solar.” 

Research Mode

Rich started to learn as much as he could about off-grid power systems and what other homeowners have learned through trial and error. “All equipment has a life span, but I didn't want to find myself in a situation where we have to replace inverters because a battery goes down or worry about components failing and paying a technician to drive to our place to make repairs.” Buying a power system is already expensive, and Rich and Julie want some protection from unexpected costs down the road.

In reaching out to solar installers, Rich found that few were using lithium batteries. “That was something I knew I did not want to deal with: the old-style lead acids, topping them off, building a separate room. Just thinking about the mess and the maintenance of lead-acid made bringing a power line in look like a good idea again! Thankfully, we contacted Intelligent Controls for some design help, and they referred us to our installer, Eric Enquist.”

Electrician and Victron installer Eric Enquist of Boulder Electric is a rare find. “Eric’s work is just unbelievable. I still cannot get over how meticulous he was as an installer. Then, weeks after the installation, he monitored our system from VRM and helped us understand how it worked. He made some adjustments, and we know we can call him at any point with a question.”

While builders were breaking ground on the house, Julie and Rich were across the country, working with Eric over the phone to plan their off-grid power system. 

“Initially, we thought we would put the batteries, solar panels, and everything else down in our workshop, which is set far apart from the house,” says Julie. “Everyone had said, ‘You can’t have the batteries in the house.” Instead, they learned that LiFePO4 batteries are safe to install inside the home - and that they could save about two to three thousand dollars in wire and trenching costs by not running cables from the shop to the house.

Eric, who himself lives off-grid with a family of 5, was able to offer a first-hand perspective on what they would need, based on their expectations and budget. Ultimately, Rich was sold on using Victron equipment because of its reputation for quality and low failure rates, UL Certification (which was required by his home insurance company), and the ability to add a third inverter or solar charge controller in one year or ten years from now - should they decide to expand their system. 

Purpose-built

Designed to supply a medium-sized, full-time use home, Rich and Julie’s system includes: 

• 2 x MultiPlus-II 48/3000/35-50 120V (UL), providing continuous 3000VA of power on each leg in a split phase configuration 
• 2x SmartSolar MPPT 250/100-Tr VE.Can harvest power from solar arrays for storage in the battery bank
• 2 x Lynx Distributors
• Lynx Shunt VE.Can
• A Cerbo GX connected via Starlink serves as the communication hub between connected devices, including the battery bank, to coordinate power demand and storage. System data is available online through the Cerbo GX and to the homeowners and their installer via Victron’s remote management platform, VRM
• A GX Touch 70 also displays the system’s status and device-specific data 
• 5 x Pylontech US5000 48 Volt LiFePO4 battery bank providing 24kWh of energy storage 
• 20 x 470W solar panels providing nearly 10,000W of PV power 
• Winco 12kw Generator with start/stop triggered by the Cerbo’s generator start/stop relay 

“The installation is a significant step up from what you'd see in a more basic, off-grid cabin,” says Eric Enquist. The system would have to supply typical loads such as the well pump and appliances as well as heat pumps for the home’s radiant heating system in the floors and outdoor lighting. 

Rich wasn’t interested in cutting corners regarding components or limiting their power consumption to the bare minimum. “I told Eric: I’ve persuaded my wife to move to a mountaintop in Montana, and her only stipulation is: I don't want this power system to rule our life. We understood we would need to make some conscious adjustments, like not running the dishwasher and the dryer at night. Still, it was helpful to have Eric, who lives with a Victron power system full time, answer all our questions and help set our expectations for the power system.”

Eric configured the system, such that if the inverters are overloaded - by, for example, all the major appliances being run at the same time, the generator is wired to turn on and will assist with those loads, then turn itself off once the battery bank has recharged to 90%. 

From VRM, Victron’s free remote management portal, Rich and Julie can see their whole system working in real time. “We love looking at the mobile app,” says Julie. “It’s just fun to look and see how many kW we made today, how it dropped down on a cloudy day, or to see our battery capacity after running a load of laundry. We’re still learning how it all works but mostly, I really appreciate checking in when we’re not at home and seeing that everything is working as it should.” 

Future-ready

Before Rich and Julie moved in, they decided to add another Pylontech battery to their bank of four. “We had some room in our budget and decided we did want the extra battery capacity to account for cloudy days or winter days when it’s already dark by 4 pm.” 

The fact that both Victron components and Pylontech lithium batteries were made to be firmware-compatible with newer models was a big selling point. “Knowing that we'll be able to just add another battery to the stack after the initial installation, or add another MultiPlus inverter in the string, means that we can adjust or expand the system in the future - if we need to.”

That day may come sooner than they think! This summer, Julie’s parents came out for their first visit. “To my surprise, they absolutely love it out here and have already told us they’re coming for the summer next year,” says Julie. We made some adjustments while they were here, but I didn’t have to say, ‘Mom, you can't run the blender right now, or please turn off the lights.’ The system is working great, and we can’t wait to share this place with our family.”

Designing a power system for your home or cabin? Get in touch. We’ll help you start on the right path. To schedule a site visit or to connect with Boulder Electric, visit https://www.boulderelectricmt.com/.