Keep it in the bank: Solar shines where the power’s pricey

The Cayman Islands come with a catch-22: some of the world’s most idyllic beaches and an outdated, unstable electrical grid with prohibitively expensive power. These two came to a head for resident Jim Knapp after 2004’s Hurricane Ivan, which left the small island nation without power for nearly four months. Knapp then decided to take control of the situation and make sure he wasn’t left in the dark again.

Sunny Islands run the show for Knapp’s Cayman Island home.

Then and now

When Knapp and his wife, Judy, first decided to install solar, electricity cost 28 cents per kWh. Six years into their nine-year payback period, electrical rates have risen an astonishing 50 percent to 42 cents per kWh. Those sharp cost increases made the island’s near-monthly grid outages, which last anywhere from one to 10 hours, difficult to swallow and made their decision to install solar worth every dollar.

Knapp’s home was the first in the Cayman Islands to install solar, leaving him to face more than his share of skeptics; questions were asked about solar’s ability to produce reliable power and whether or not he was trying to make money off his system by selling power back into the grid. To ensure the solar system wasn’t in violation of local laws prohibiting selling energy back into the electrical grid, the system was configured strictly for self-consumption, with the electric grid tied in for consumption only—a backup power source.

Three Sunny Boy inverters busy at work in the Cayman Islands.

Money in the (battery) bank

Knapp’s system consists of 80 BYD 240-watt modules sending power to two Sunny Island 5048-US off-grid inverters, one Sunny Boy 7000-US and two Sunny Boy 4000-US inverters. Power is either fed directly into the home or stored in a battery bank for use during non-daylight hours.

The 19.2 kW (DC) system produces 27,216 kWh (AC) annually. Through energy efficiency upgrades and demand reduction, Knapp and his wife currently use approximately 20,000 kWh of power. Since becoming 100 percent grid-independent, Knapp is now considering disconnecting his grid connection entirely to save on his annual meter rental charge.

Help from afar

Despite being thousands of miles away, Knapp has been able to rely on the SMA Service Line to ensure his system runs smoothly. Not long after its commissioning, the original installer was never to be heard from again. Luckily, SMA’s service techs were able to educate and guide Knapp to properly maintaining the system and even performing the occasional round of troubleshooting.

Since installing his solar system, Cayman Appraisers have increased the value of his home by $12.30 (CI) per $1 of operating costs, equaling $147,000 in added home value. With that added value and the security of never being without power again, these homeowners can put their feet up and enjoy the sunshine.