September 2020

Chris Sparadeo

In the past, flooded lead-acid (FLA) batteries have been the first choice for those living off-grid. Although they have historically been the backbone of remote electrification, these batteries come with tradeoffs. Off-gassing, equalization charge, hydrometer readings are concepts that off-grid homeowners have come to grudgingly accept as part of the love-hate relationship with their battery banks.

In recent years, there have been major advances in battery-storage technology that have revolutionized the way power is stored and accessed. We now have a multitude of new chemistries, from salt water to numerous new lithium variations. Storing energy is becoming safer and easier as the revolution is ongoing.

One battery chemistry, lithium iron phosphate (LiFePO₄), has emerged as a shining star. These batteries have a 100% depth of discharge capability, no noxious off-gassing, and a long lifespan. They offer an extremely stable battery chemistry not susceptible to thermal runaway. They often come with robust manufacturer warranties. Also, unlike FLA batteries, LiFePO₄ batteries will likely supply rated storage capacity, regardless of how fast the power is drawn from it.

With LiFePO₄, there are plenty of choices when it comes to size, style, price, and options.

A manufacturer based in Pennsylvania, Fortress Power, and its 48-volt offering, the eVault 18.5kWh, present a perfect combination of performance and price. Each cabinet supplies a massive 18.5 kWh of usable energy storage and up to twelve units can be combined for a total of 222 kWh. The batteries have fast charging and discharging abilities, reducing the time it takes to charge. Fortress Power, with its integrated bussing system, has also solved the issue of inter-cell resistance, which can lead to reduced life span and performance.

The eVault’s most eye-catching feature is its digital display touch screen interface that provides data on the battery’s state of charge (SOC), along with charging and discharging statistics. This display is very important, as those who have used FLAs will appreciate. With typical lead-acid batteries, the user reads the voltage from a charge controller or inverter to understand the SOC. Unfortunately, FLA batteries and their voltage-based readings are imprecise at best, and even advanced battery-monitoring devices eventually fall out of calibration, leaving a user with an inaccurate understanding of the battery bank’s actual SOC.

FLA voltage readings can vary widely during normal operation, from often 44 to 52V at resting states.

LiFePO₄ chemistry is such that usable SOC typically exists in between 52 and 54V. This means at 53 volts, a battery bank might very well be at 80% SOC, but at 51.5 volts somewhere around 10%. This is a tight window of voltage, and the SOC of a LiFePO₄ battery is not only established from voltage, but also determined by charging and discharging current. The eVault’s highly sophisticated battery-monitoring unit and integrated display screen give a precise reading of SOC, whereas screenless LiFePO4 batteries relying on voltage-based readings may not be as accurate.

Today, we are clearly in a new age for energy storage. Whether it be an off-grid, grid-tied battery backup, or an uninterruptable power source (UPS) system, the 18.5 kWh eVault offers reliable storage at an accessible cost, comparable to other makers’ batteries. It has a 10 year/6,000 cycle warranty, three years more than most of its competitors.

Homeowner Joe Hester Ingram has had experience with the Fortress eVault battery. He recommends it, saying, “I have been using off-grid solar to power our home in Wolcott, Vermont since the late 1970’s. I had been using the standard deep-cycle lead acid type batteries in my system. They have always been a challenge to manage all these years, with the need to monitor fluid levels and state of charge, with their life in service always being fewer years than I had always hoped for, with declining capacity as they aged. In October 2019, Catamount Solar replaced my system with new panels, controls, and batteries. The battery cabinet is the Fortress eVault 18.5. I have been extremely pleased with their performance, the freedom from monitoring and maintenance, and especially the LCD screen displaying state of charge information available at a glance on the front of the cabinet. The ten-year warranty adds promise to my new confidence going forward.” Ingram re-used the old system for a cabin on his property.

Gail Boyajian of Strafford, Vermont said of her new eVault, “Its compact footprint, the fact that it’s sealed so that there’s no issue of off-gassing and it’s energy density compared with the lead acid batteries it has replaced, make it a vastly superior storage system.”

Learn more about Fortress Power batteries at fortresspower.com or at (877) 497 6937.

Chris Sparadeo is a NABCEP Certified Professional PV Installer and is a member-owner of Catamount Solar as their off-grid specialist. Chris has been working in battery-based, off-grid solutions for nearly a decade. Feel free to send him an email with your questions at [email protected].

Battery Storage Choices Grow with Fortress Power

On June 2012, 27-year-old Jing Yu traveled across the Atlantic and landed in New York with two suitcases and a working visa. She was tasked with setting up U.S. operations for a German solar company.

In addition to registering the company and finding the right location to operate, Jing would have to handle everything herself – management, sales and marketing, accounting, and more – until she could start building a team.

This was no small undertaking. However, Jing was no stranger to big moves and challenges.

As a college student in China, Jing had never left her home country. Back then, traveling abroad was a major expense. However, after attending college in China for two years, curiosity and ambition led Jing and a group of students to Germany in 2004 to continue their education as part of a joint program between two universities.

While attending school in Germany, Jing discovered her passion for renewable energy, especially solar. She completed her studies while focusing on solar technology research, earning a master’s degree in electrical engineering from Fachhochschule Hannover and an MBA from the University of Würzburg.

“The world is behind schedule in slowing climate change,” Jing said. “I believe we’re all obligated to protect the environment and I take that responsibility very seriously. My generation needs to recognize the urgency of climate change and make renewable energy a top priority.”

Jing landed her first job out of college with WINAICO Solar in Germany, where she quickly advanced to general manager. The company wanted to expand to other territories, including the U.S. and asked Jing if she was up for another challenge.

“They wanted to me start up their U.S. operation,” Jing said. “I remember my mother giving me a push to accept the offer. She said that if I wanted to go to America and explore new opportunities, I should do it. I’m very lucky to have parents who support me in everything I do.”

Building a Renewable Energy Company from the Ground Up

Jing made the bold move to the U.S. with nothing but those two suitcases as she built the new WINAICO operation from scratch. Starting a business is difficult enough. Moving to a different part of the world to start a new business adds a whole new layer of obstacles.

For example, something as simple as opening a bank account was far more complicated without a Social Security number. Jing spoke English, but with a unique Chinese-German accent, she had developed over the course of eight years in Germany. Fortunately, she met a friendly banker who helped her overcome these hurdles and create a solid foundation for the company.

Jing and eventually settled in Jersey City, NJ, hired a salesperson, and traveled to different parts of the country to visit solar installers. She carried a silver suitcase with a small solar panel inside to show potential customers. Four months later, they landed their first customer, a solar installer in Vermont, and the business started to take off.

How a Chance Meeting Led to Fortress Power

Jing met Barry Moore, President of Moore Energy, at a trade show in Connecticut. Barry introduced Jing to his engineer and they were both very impressed by Jing’s solar product. Barry’s company became a client, but it wasn’t long before a strategic partnership began to develop.

“Barry suggested I move to Pennsylvania,” Jing said. “I realized I would be able to have more warehouse and office space at a much lower cost in Bucks County, and I loved the community. Barry and his wife actually came to Jersey City to help us make the move.”

Soon after the move, Barry landed a large contract with SEPTA (Southeastern Pennsylvania Transportation Authority), which needed a solar and battery backup system to power various parts of its infrastructure. Jing had been researching different battery chemistries and identified lithium-iron-phosphate as the ideal chemistry for this application.

The initial project has delivered positive results and SEPTA has approved funds for additional battery storage initiatives. Recognizing the need for modern, reliable battery power backup solutions in both the residential and commercial markets, Fortress Power was formed in early 2017, with Jing serving as CEO.

A New Generation of Solar Leaders

Although more women are in senior leadership positions today, the solar industry, historically, has been dominated by men. That hasn’t stopped Jing Yu from advancing from an undergraduate student in China, to multiple master’s degrees from top universities in Germany, to the successful launch of a solar company in the U.S., to CEO of one of the world’s top energy storage battery manufacturers – all by the age of 32.

Jing, now 35, has a strong technical and business background, but also attributes her accomplishments to a little bit of luck, a lot of hard work, and good people.

“My mom is my role model,” Jing said. “She grew up in the countryside of China. As a teacher and small business owner, she taught me the importance of hard work and self-confidence. I’m trying to teach the same values to my daughters (ages 4 years and 4 months old).”

Jing is grateful for the people who have helped her throughout her journey, from Barry Moore to the friendly banker who helped her get settled, to the early customers who trusted Jing’s expertise. She especially appreciates the Fortress Power team, which is committed to constant improvement and solving problems for customers.

Jing also hopes her story will inspire the next generation of young women to become leaders in science and renewable energy. Her advice is simple: don’t be afraid of challenges.

“You have to be confident in who you are,” Jing said. “Find out what you like to do and go after it. Surround yourself with good people. You may fail, but at least try. After all, you learn more from your failures than your successes. The most important thing is to stay true to yourself and believe in yourself. With the right mindset, there’s nothing you can’t accomplish.”

 

 

 

 

Fortress Power Team                   Jing with Alex Lepore & Andrew Parker (Sales)