Dr. Earl Bakken invented the world’s first wearable, battery-operated external pacemaker, helping launch the modern medical-technology industry. His interest in and commitment to innovation, technology and health extends to this day, and to his home in Kiholo Bay, North Kona Coast, Big Island of Hawaii, called The Bakken Hale at Kiholo Bay. Because his property is remotely located, it’s off-grid, which for the past 20+ years has meant running everything on propane generators even as the Bakkens desired something more environmentally friendly. When new battery storage technology was recently developed, the Bakkens were finally able to make the long-desired move to solar energy. With the ability to run the entire property using solar power, the Bakkens and their team took on two significant projects: renovating the mechanical systems in the 10,980-square-foot residence and building a 2,000-square-foot battery storage building to store the energy produced by a new solar array. In both cases, Variable Refrigerant Flow (VRF) technology from Mitsubishi Electric Cooling & Heating (Mitsubishi Electric) was selected for its efficiency and reliability.
Clemson Lam, AIA, architect, Clemson Lam Architect AIA, Kamuela, Hawaii, designed the Bakkens’ residence in 1987. He said, “The home is in a remote location, so there were no municipal facilities like water or power or phone or anything like that. They had to develop all of that themselves, and from the time they moved in until just recently, they were burning propane for their power; propane is very costly and is a relatively hazardous material. The Bakkens also wanted to have a model system that could serve as an educational tool for school kids, so they wanted to go to a photovoltaic system.”
Adam Atwood, general manager, Bakken Hale at Kiholo Bay, also served as the project manager on the Photovoltaic Plant Construction Project. He said, “We’ve been trying to convert this property to solar for over 20 years, but the battery technology just hasn’t existed.” Without the proper technology to install or an urgent need, the property remained on propane indefinitely. Fortunately in 2011, the team was finally able to take action in the way they wanted because a new battery had just been developed. It was sealed, required zero maintenance and was completely non-toxic. But it was also so new that it was completely unproven. Dr. Bakken, always the innovator, was enthusiastic about the idea.
Challenge: Finding a cooling and heating system for a new home addition that could also solve years of comfort issues in the home’s original areas
Renewable Energy Services Inc., Honoka’a, Hawaii, served as the design-build contractor. Peter Shackleford, president, said, “Due to our proximity to the ocean and heavy salt spray, we decided to build a tsunami-proof, hurricane-proof and earthquake-proof battery enclosure that’s over 2,000 square feet. So that requires HVAC.”
Atwood laid out the criteria for the new HVAC systems that would be installed in both the battery storage building and the residence: “Easy maintenance in the face of an extraordinarily saline environment and 24/7/365 reliability with no opportunity for downtime whatsoever. We also needed very, very clean air because the Bakkens were concerned about vog – a mix of environmental haze and volcanic ash that affects some people’s health.”
Finally, the new battery storage building would have to meet a certain aesthetic. Lam said, “Beyond just functioning as enclosing the batteries andcontrols, the team wanted this building to relate somehow to the original house.” The goal: elegant industrial architecture.
All signs pointed to VRF. William D. Gordon, president, Gordon Sheet Metal Inc., Kailua-Kona, said, “The problem they were having in the residence is that the starting load on the dinosaur equipment – older style packaged units from when the house was built – was huge. Approximately 60 amps. That’s really hard on batteries to have big surges. Mitsubishi [Electric] equipment’s starting load amps are so low compared to that. With PUMY condensers, you’re looking at 5-8 amps. And the Mitsubishi [Electric] system would flatten the load out as much as possible, avoiding the peak startups that the older style compressors had.”
Solution: Zoned Comfort Solutions™ from Mitsubishi Electric
For the battery storage building, Atwood said, “It’s got to be a certain humidity and temperature level so the batteries operate at maximum efficiency. It was mission critical that energy be delivered efficiently.” To meet that need, Gordon suggested PEFY units from Mitsubishi Electric. “The batteries are state-of-the-art and put off very little heat. Still, something was needed; the Bakkens were creating this building almost as a classroom environment. Dr. Bakken wanted to be sure that if he had a lot of people showing up to do a tour – 30 people, a classroom of kids – that they had an appropriate amount of fresh air, and that they would be able to get rid of gasification. So we recommended PEFY units for their accessibility, and a Lossnay® unit for fresh air.”
Gordon stands by Mitsubishi Electric after six successful years with the brand. He said, “The first VRF we ever installed was another brand. As we became more familiar with VRF, I found Mitsubishi [Electric] not only has a superior product line, but their technical and engineering support is far superior. Our distributor is AC Warehouse and they’re great. They offer good technical support and carry a large inventory so it’s easy to get the product we need when we need it.”
The installations required creativity. John Tagupa, lead service tech, Gordon Sheet Metal, said, “A tsunami had washed through years ago, so knowing that could happen we suspended the PUMY condensers from the bottom of the ceiling of the residence’s slab, so they’re raised off the ground. And instead of using brackets, we designed a trapeze system – the best way to add seismic capabilities. We also used all stainless steel components to prevent rusting, given the proximity to the ocean. And on top of the Blue Fin coating that comes standard on the PUMYs, we did anti-corrosion coating, as well.”
Result: A non-disruptive installation, comfort throughout the entire home and impressive efficiency
Controls were also a big part of the installation. Gordon described the on-site monitoring system as “incredibly sophisticated. The Bakkens know exactly how many kilowatts they’re using any time of day.” Tagupa said remote controllers offer additional monitoring: “Dr. Bakken’s son lives in Minnesota. We set him up with the Zone Control app so he can monitor everything from there – just to keep him in the loop.” Likewise, Atwood required remote access: “I need to be able to diagnose any problem right away, whether it’s user error or an actual mechanical malfunction. And I need to be able to diagnose from anywhere, including when I’m traveling.”
Going back to the core goals of the project, Atwood said, “We want to be as fossil fuel free and environmentally friendly as possible. Our a/c systems were taking up a very large part of our energy consumption, so by installing the new systems, not only did we upgrade for reliability, but we also brought the energy usage down for the entire property dramatically. For example in the evenings, our energy usage with generators was 20-24 kW. With the new a/c system, we’re hovering around 10 kW now.”
Having such an energy-efficient system has also been crucial during recent hot summers. Atwood said, “We’ve seen a dramatic increase in temperatures the last two years here. I don’t know if it’s global warming or El Niño, but temperatures and humidity have gone from being very comfortable to almost unbearable. It’s been so brutally hot the last couple summers that we’ve had max a/c going in every part of the property that’s air conditioned. So that’s a big increase in our energy consumption. But having our new, state-of-the-art Mitsubishi [Electric] HVAC systems has really been great in reliability, efficiency, less servicing and also our critical function of bringing our energy costs and consumptions down. We’re
really happy with the direction we went.”