Hawaii
New Report Illuminates Geothermal Cooling Potential in Hawaii – CleanTechnica
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University of Hawaii at Manoa and Lawrence Berkeley National Laboratory Teamed up To Analyze Feasibility of Geothermal Cooling Technologies
By Justin Daugherty, NLR
In areas with geologically recent volcanic activity and ample underground water flow, like the Hawaiian Islands, geothermal energy technologies present options to augment the electric grid.
To investigate building cooling and energy efficiency options, the University of Hawaii at Manoa’s Hawaii Groundwater and Geothermal Resources Center collaborated with scientists at Lawrence Berkeley National Laboratory through the U.S. Department of Energy’s Energy Technology Innovation Partnership Project (ETIPP).
Managed by the National Laboratory of the Rockies (NLR), formerly known as NREL, ETIPP supports remote, coastal, and island communities with technical assistance and energy planning to help them build more reliable and affordable energy systems. Communities apply for up to 24 months of technical assistance, and those communities drive the scopes and focuses of their energy projects.
University of Hawaii at Manoa joined the program in 2022 with a desire to explore geothermal options, and a new report from this project details the feasibility of developing shallow ground heat exchangers (GHEs) across Oahu and at a specific site on the island for cooling.
Geothermal heat pumps take advantage of relatively constant temperatures just under the earth’s surface, using GHEs to exchange heat with the earth. Through a system of looping pipes in the shallow ground, GHEs can move heat from a warm place to a cooler place, like how a refrigerator functions.
“High-temperature geothermal, which requires deep drilling, is required to produce electricity, but low-temperature geothermal such as GHEs, which can be accessed much nearer the ground surface, can be used for building heating and cooling, greatly lessening loads on the electric grid,” said Lawrence Berkeley National Laboratory’s Christine Doughty, staff scientist.
“I believe both types of geothermal have potential to be an asset to Hawaii,” added Nicole Lautze, founder and director of the Hawaii Groundwater and Geothermal Resources Center.
Determining Geothermal Cooling Favorability in Hawaii
In open-loop geothermal systems, wells are drilled to extract and inject groundwater, allowing the movement of thermal heat to and from the earth. These GHEs use cooler ground water from outside the system for the cooling process and expel the warmer water afterward.
In contrast, closed-loop GHE systems continually circulate a heat-transfer solution through pipes, which transfers heat to and from the ground via thermal conduction. Groundwater needs to have temperatures that are low enough to effectively cool buildings, and groundwater flow in a GHE system works to remove built-up heat.
Hawaii has far greater needs for cooling than for heating—meaning that GHEs would add heat to the subsurface and cause the systems to not function as desired. That is where groundwater comes in: It replaces heated water from the boreholes and maintains the functionality of the GHE system. Sufficient groundwater flow, then, is essential to the considerations for GHE deployment. GHE systems may not be deployed in areas with restricted watersheds or where there is subsurface production of freshwater. Therefore, closed-loop systems may be a more reasonable option in some locations.
Numerous factors help determine whether a community or business may consider GHEs. Areas with older homes may lack efficient energy systems, and some organizations, like schools or government buildings, may prioritize more adaptive heating and cooling. Cultural considerations are also very important, and a new NLR report incorporates Hawaii communities’ perspectives on geothermal.
Economic factors are another big consideration, with the expense of deploying a system versus energy savings playing into overall cost. Modeling revealed that electricity and energy transfer demand decreased, and such reductions contributed to cost savings. Longer loan terms may help ease deployment expenses for geothermal systems.
ETIPP researchers factored the above parameters into their analysis to develop favorability maps for closed-loop and open-loop GHE systems. They used specific geographic information system layers with 11 attributes—including elevation, geology, and soil permeability—to develop an overall favorability map for GHEs on Oahu.
For the site-specific feasibility analysis at the University of Hawaii at Manoa’s Stan Sheriff Center, researchers used a hydrogeologic model to analyze groundwater flow of a closed-loop system at the site. Restrictions on water quality—mandating that groundwater must be left in its natural state—diminished the available area for GHE system deployment across the island, while many coastal areas showed high favorability. Overlays showing potential customers and restricted areas sharpened the maps.
Geothermal Cooling Potential at University of Hawaii at Manoa
From the island-wide analysis, ETIPP analysis homed in and found that the Stan Sheriff Center at the University of Hawaii at Manoa, a building with a high cooling load in an area with lots of open space surrounding it, could make a good candidate for site-specific analysis of GHE technology.
Researchers used a hydrogeologic model to analyze a potential closed-loop system at the site. They modeled groundwater and heat flow, analyzed subsurface heat flow, and completed a techno-economic analysis.
Analysis without groundwater flow showed that the GHE system may operate normally in the first year, but heat buildup would increase water temperatures significantly after that, and without groundwater to sweep heat away, there would be increased chiller demand in years two through six. Modeling that incorporated groundwater flow—with similar conditions as the Stan Sheriff Center—showed that heat would be effectively swept away from the borefield, which would enable successful GHE operation for at least 10 years. Thus, including groundwater in analysis and planning—coupled with low interest loan rates and high capital investment—may provide economic benefits to the university.
Cold seawater may be an option for cooling-source systems, the analysis concluded, and such a system already operates at the Natural Energy Laboratory of Hawaii. The report authors encouraged further study.
As in Hawaii, ETIPP continues to help communities explore geothermal and other technologies to help meet their energy needs through in-depth, collaborative investigation of potential solutions.
“This ETIPP project established a strong collaboration with LBNL and the foundation for what I hope is additional grant funding to explore the potential of GHEs on the UHM campus and across the state to cool buildings and reduce load on Hawaii’s grid,” Lautze said.
The U.S. Department of Energy’s Energy Technology Innovation Partnership Project (ETIPP) is a community-led technical support program for coastal, remote, and island communities to access unique solutions and increase energy reliability. By uniting federal agencies, national laboratories, regional organizations, and community stakeholders, ETIPP provides tailored technical support to help communities achieve affordable, reliable solutions to their energy system challenges. This collaborative model leverages the combined expertise and resources of its partners to deliver comprehensive, practical solutions that align with local needs. Learn more about ETIPP.
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County approval sought for festival that has irritated neighbors – West Hawaii Today
Hawaii
Tourist yells ‘I’m rich’ after beachgoers beg him to stop attacking endangered seal — before he’s detained
A tourist who threw a huge rock at an endangered Hawaiian monk seal in Maui boasted that he didn’t care about the consequences because he’s “rich” — before he was detained over the attack.
The man was filmed lifting a large rock from a beach and throwing it towards an endangered seal as it swam off the Lahaina shoreline last Tuesday, narrowly missing the animal’s head.
Kaylee Schnitzer, who filmed the video, can be heard yelling at the man: “What are you doing? Why would you throw a rock at it?”
She later told KHON 2: “We told him that we called the cops, and he was like, ‘I don’t care. Fine me, I’m rich.’ He said that, and he kept walking.”
The Division of Conservation and Resources Enforcement’s Maui Branch dispatched officers to the beach, where they detained the suspect. Hawaii’s Department of Land and Natural Resources said it will not be share the suspect’s identity as he has not been criminally charged at this time. He is understood to be a 37-year-old man from Seattle, Washington.
A viral video captured a tourist throwing a large rock at an endangered monk seal in Hawaii (KHON2)
Hawaiian monk seals are among the most endangered marine mammals in the world. Harassing, injuring or killing one is against both state and federal law, and violators may face fines or criminal penalties. The horrifying incident sparked online outrage and Schnitzer’s video went viral.
The seal, named “Lani,” is beloved by many residents in the area after returning to Lahaina following the 2023 wildfires. Maui Mayor Richard Bissen noted in an Instagram post that both members of his team and locals have “watched over and deeply cared for” Lani since her return.
“Let me be clear, this is not the kind of visitor we welcome on Maui,” Bissen said. “We welcome respectful visitors that understand that our cultural environment and wildlife must be treated with care and aloha. Behavior like this will not be tolerated.”
Monk seals are one of the most endangered marine mammals in the world (Hawaii Department of Land and Natural Resources)
State officials said the suspect was questioned by authorities and later released after he requested legal counsel.
The Department of Land and Natural Resources said it is investigating the incident and will turn over the findings to NOAA’s Office of Law Enforcement for possible federal action. The Independent has contacted the department for more information.
During a news conference on Wednesday, the Division of Conservation and Resources Enforcement Chief Jason Redulla said officials have not confirmed whether the seal was harmed by the rock.
Police reminded the public to avoid interactions with the protected species and report harmful behavior to authorities.
Hawaii
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