Off the grid

As for so many people in Grand Cayman, 2004 was a life-changing year for Jim Knapp and his wife Judy VanLiere whose home was hit by Hurricane Ivan.

Amidst the post-storm carnage, they vowed to switch to a more sustainable lifestyle and avoid ever again being caught out in an island-wide destruction and shut-down of utility services.

“Our condo had no power or water for months and yet our boat was completely operational (water maker, air conditioner, radios, freezer and fridge) because of two small solar panels,” says Jim.

In those terrible weeks following the Category 5 storm, the couple decided to build a house that could not only withstand a future hurricane but also be completely self-sufficient, just as their boat had been.

“We were committed to building in a new way and started two years of research into renewable energy and design,” Jim recalls.

They broke ground in Bimini Drive in June 2008 and now, 10 years after Ivan, they are living in a house that is almost completely off the grid.

Design & Technology 

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“The house is ultra-contemporary,” says Jim. “It’s a tropical modern design with every energy-efficient design characteristic known to man incorporated at the time it was built.”

The home incorporates several primary renewable energy technologies plus many energy-efficiency items. 

First and foremost is the solar power: the home is equipped with a 19.2 kilowatt solar array consisting of 80 solar panels that cover approximately 55 percent of the available roof space. 

These panels produce all of the energy that the home requires to power it during the day, and also produces excess energy needed to charge a bank of 72 absorbent glass mat batteries for powering the home at night and during inclement weather.

Second is the 27 seasonal energy efficient ratio geothermal heat pump for air conditioning. 

This system uses a closed loop of water that moves the warm temperature from inside the house to the ground outside. 

“You can carry 3,000 times more heat in a cubic foot of water than you can in a cubic foot of air,” Jim explains.

“Yet, in the Caribbean, everyone uses air-to-air heat pumps.  

“Another benefit is that all our hot water is produced for free by our air conditioner. The hot water in the loop passes through the water heater and heats up the water inside the tank before it moves on. 

“The water, traveling in the loop, cools off quickly as it moves through the ground in its plastic pipe. Once the water temperature is cooled in the loop it makes the same cycle again and again, taking out the heat. 

“These units were rated at nearly 70 percent more efficient than a standard heat pump when we built the house. To be honest though, there have been significant improvements to the energy efficiency in regular AC systems with variable speed compressors since then.”

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In addition to these renewable energy systems, the home uses an induction cooktop and convection ovens, LED lighting and special tinted hurricane-rated windows.

Finally, Jim has multiple-energy monitoring systems which allow the couple to see every watt of electricity that their home uses, right down to the individual plug or socket. 

“We can remotely control the AC and modern appliances as well as monitor for water leaks and more,” says Jim. “It will tell us if we left the tea or coffee pot plugged in and running, or warn us if any dangerous electrical condition exists in our home.  It can call us, send us text messages or emails as we choose. It’s absolutely incredible.”

Having been settled in the house for several years now, the Knapps are delighted at the performance of the technology and are saving around $1,000 each month in cash formerly spent on utility bills in their condo.  

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Jim Knapp’s solar batteries

1 COMMENT

  1. More of this is needed in this land of sun and fun, but it is still expensive. Government incentives, and CUC and CBP&L offering expertise and product sales and service, would certainly help some of us navigate the morass of this kind of logical initiative. Well done Jim and Judy.