Ham radio operation dates back to the early 1900s and today numbers over 2 million people throughout the world who are engaged in non-commercial broadcasting of messages over the radio. Ham radio operators have come to be considered hobbyists but for most, like Glenn and Vivien Johnson, it’s more than just a hobby—it’s a way of communicating with people around the world. That is one of the reasons why the Johnsons decided to invest in solar + storage to ensure that their radio operation is always up and running. Like many ham radio aficionados, Glenn Johnson trusts that ham radio will always come through in a disaster, “Even when all other forms of communication are compromised or electrical power is unavailable,” he said. And having energy storage as a backup to a solar energy system seemed like the smart way to go.
The Johnsons live in rural Iowa (US), where winters can be harsh and unrelenting, sometimes bringing down the local power grid and rendering them incommunicado as far as ham radio operating goes. They had been using a portable generator in times of power outages, but they recently installed solar panels with an energy storage system. They worked with local company Decorah Electric to design a hybrid grid-connected solar + storage system to keep them up and running at all times, as well as to save on energy costs. When choosing what products to use in their solar power projects, Joel Teslow of Decorah Electric depends on the advice of Werner Electric Supply, which specializes in renewable energy. As far as choosing the storage products, that decision was made clear for Teslow after he was invited by Werner to go to OutBack Power headquarters for a five-day training course. “I got to know a lot of the people within the company that you don’t usually get to talked to, and I liked the product,” Teslow said.
Designing the solar + storage system
One challenge to designing the solar + storage system was that the Johnson’s have two separate buildings with separate electrical loads. One building, which is their home, has the greater load that runs all household electrical systems as well as their ham radio operation. The second building is a barn and shop, which has lighting and floor heat that keeps water lines from freezing. Altogether, the Johnsons consume approximately 18,000 kilowatt hours a year.
For the household system, they installed four 3.75kW top-of-pole mounted SolarWorld 250W poly solar systems. Teslow said the reason he chose the top-of-pole mounting system was “to allow the customer to manually change the tilt angle of the arrays throughout the year to help maximize his energy harvest.” He added that the cost of a single or dual axis tracking system “was not appealing to the customer in this case”
The inverter room
For energy storage they are using a 2-stack Radian system and an EnergyCell 1600RE high- capacity battery bank, all from OutBack Power. For the barn and shop, they have two 3.75 kW top-of-pole solar systems that match those on the house. They have an 8kW Radian inverter/charger and two 16-cell EnergyCell 200RE battery banks in two OutBack Integrated Battery Racks.
The 8kW Radian inverter/charger and two 16-cell EnergyCell 200RE battery banks
The EnergyCell RE batteries are based on advanced Absorbed Glass Matt (AGM) technology. They’re maintenance-free batteries, and the preferred choice for Teslow. “We do use some flooded cell batteries, but typically we try to steer people toward sealed AGMs.” The solar + storage installation is monitored remotely using OutBack’s Optics RE monitoring and control system.
The benefit of autonomy
The system is producing 30,000 kWh, which is more than they use, allowing the Johnson’s to not only store enough for three days’ use, but to sell some back to the utility—resulting in a net-zero electric bill. For the Johnson’s, the autonomy is a great benefit. “We have assurance that no matter what happens to the grid, we can get by with electricity for the critical loads in both our house and our barn, and we’ll be able to communicate with anyone in the world,” Glenn Johnson said.
Written by Anne Fischer, Managing Editor, Solar Novus Today