Chuck Henry is serious about sustainability, but he had the crowd chuckling at the Washington State Technology Summit.

Sitting on a four-man panel April 15 at the Meydenbauer Center in Bellevue, the Eastside Preparatory School of Kirkland instructor broke a smile when it was his turn to speak.

“The compost toilet I invented really isn’t that sexy,” he said. “How many of you are going to drive your toilet to the ballet?”

Surrounded by men discussing nanotechnology, energy storage and renewable-energy heating solutions during the morning session, Henry certainly stood apart from the crowd. The doctor’s topic was of great interest, too, as several attendees chatted with him afterward.

Henry, who has taught about and researched sustainable practices and environmental science for 25 years, has spent the last seven years perfecting his Earth Auger toilet. First up was a food-waste composter made of a 10-foot PVC-pipe component, and two years later he built his toilet prototype — featuring a 7-foot PVC-pipe component hooked into the unit — at his Cle Elum cabin. Currently, Henry’s toilets are being used in Ecuador and Costa Rica, where he hopes to “foster economically and environmentally sound handling of biological waste through use of composting toilets,” according to his vision statement. Future plans include constructing toilets in Kenya and poor communities in the Galapagos Islands and Andes Mountains.

Henry entertained the idea for his compost toilet while on a sustainable-practices trip to India.

“It came to me in the middle of the night,” he said after his summit session. “Why can’t you open a hatch, put waste down, grind it up and have it be compost by the time it gets to the end?”

In 2006, Henry led a group of University of Washington, Bothell students on a trip to rural Costa Rica, where they constructed one toilet on a remote ranch. The components were made at the university, transported to Costa Rica on a commercial flight and built into an outhouse-style unit.

There, he gained the support of Amanco PVC Pipe Company.

“They were there doing an irrigation system, and they said, ‘This is so cool, I think we want to sponsor something like this,’” said Henry, who added that the company’s enthusiasm gave him a boost of confidence.

Amanco provided free pipe for the Costa Rica toilets, but he works with a private company on the Ecuador projects. Currently, there are six units in a beach facility for tourists in Ecuador, and seven more similar facilities are in the planning stages.

Henry, who teaches full time at Eastside Prep and does research at UW-Bothell, has worked closely with the university to license his invention. When royalties roll in, Henry splits the earnings with the Technology and Transfer and Interdisciplinary Arts and Science departments.

“They got so excited about it,” Henry said.

Earlier in his summit talk, he discussed funding his and the other panelists’ projects: “Many of the things we’re involved with don’t catch the eye — it’s challenging.”

It’s certainly paying off now — for both him and the environment.