Kahuku High & Intermediate School will soon test four schemes to cool temperatures in portable classrooms, some so hot they're known on campus as "purgatory."

The most successful cooling option will be applied to buildings throughout the state's public school campuses.

The heat abatement pilot project will test passive cooling designs as opposed to installing air conditioning, a high energy user in a time of soaring electric bills.

The school has 11 portable buildings that will be part of the project that calls for modifying four buildings, with the remaining ones to be part of the control group in the experiment.

Heat in some portable classrooms is legendary, sometimes topping 100 degrees. People have taken pity on the students by donating fans and air conditioners.

The state has a heat abatement fund but at the high cost of retrofitting buildings with air conditioning, the Department of Education has calculated that it would take decades and $1.5 billion to cool all of the public schools in Hawai'i. Added to that is the cost of electricity, which the DOE estimated at $37 million last year.

This effort is an attempt to stretch the dollars in the abatement fund, which gets about $5.3 million a year from the state Legislature, and cool more schools with the same amount of money.

"While our school didn't make the (DOE's) top 10 hottest list, we do have hot spots on campus ... and (there's) a section of portables that are referred to as purgatory," said Lisa DeLong, who was the principal at the school last year when project planning began.

DeLong said the school partnered with the University of Hawai'i School of Architecture, the state Department of Business Economic Development and Tourism, Group 70 International and Lincoln Scott Inc.

"The design that gets the best results, temperature wise, will be replicated around the state," she said, adding that there are about 1,400 portables in use.

The goal was to make the portable classrooms more comfortable without air conditioning, said Scott Inatsuka, president of Lincoln Scott, a mechanical and electrical engineering firm.

"We as people know how to make ourselves comfortable," Inatsuka said. "Trying to apply that to a building is the next exercise."

The project involved Kahuku students who developed their own design along with the professionals with the intent of using their design in one of the portables. The students attended seminars given by the School of Architecture, the engineers and Group 70. They learned a new software drawing program and finished a design, said Julian Tyrell, a Kahuku teacher.

Unfortunately, learning to use the new software program took longer than anticipated, so the students were not able to meet the deadline for completion, Tyrell said.

But the possibility of using their design remains open, said Charles Kaneshiro, principal for Group 70, that is heading up the project.

"We did receive some initial ideas from the students and it really did show that they were paying attention and learning something from the exercise," Kaneshiro said.

Kaneshiro said four designs were submitted and the DOE sent out requests for bids, which are expected to be awarded by the end of the month. The work on the classrooms could begin in the fall, he said.

The options start with a basic design with added insulation, ventilation and ceiling fan, Kaneshiro said. Each subsequent design builds on the previous one except for No. 4 that uses only heat-reflecting paint, the cheapest option available, he said.

All of the options were tested with a simulation program and the best ones chosen for the demonstration project at Kahuku. Kaneshiro said they were asked to keep the cost per building to $100,000, but the team was striving to find a solution that would cost $50,000.

Money for the project comes from a heat abatement fund that was set up to air-condition Hawai'i schools. With cost estimates at around $5 million per school, schools were prioritized, but few schools have been air conditioned since the fund began about seven years ago.

If these pilot projects work to reduce the temperatures, then more schools would benefit from the fund, he said.

"I remember hearing that if they had to air condition using this fund it would take (140) years to air condition all of Hawai'i schools," Kaneshiro said. "Then electric bills would go through the roof."