From tech to tropics, LCD technology works

Kristine Gill

The same technology powering cell phones and computer monitors helps grow plants on campus

Oleg Lavrentovich is one of three professors from Kent State who is helping to develop liquid crystal technology for the Cleveland Botanical Gardens. STEPHANIE DEVER | DAILY KENT STATER

Credit: DKS Editors

The Liquid Crystal Institute and the Cleveland Botanical Garden announced their partnership last week to create greenhouses able to self-adjust, allowing for optimal heat and light intensity for specific plants.

Natalie Ronayne, executive director at the Cleveland Botanical Garden, was looking for a solution to energy conservation. She approached the university with the idea for partnership a little over a year ago.

The project is receiving grant funding totaling $58,000 – $38,000 from the Gund Foundation and $20,000 from the Bicknell Fund.

Phase one of the project involves designing a greenhouse based on current liquid crystal technology that allows panels to automatically adjust the amount of light able to pass into the greenhouse.

The greenhouses will actually be constructed in March.

“(The panels) can block out intense sunlight, or they can permit sunlight to enter depending on the needs of the plant,” said Mark Druckenbrod, project coordinator from the Cleveland Botanical Garden.

“The panels would manage the light and heat that is produced by the sun,” Druckenbrod said. “That’s a very key feature for a greenhouse to be able to achieve.”

John West, vice president for research and dean of graduate studies at Kent State, said it’s difficult to make these kinds of adjustments on regular greenhouses.

“Right now, when you want to do that in a greenhouse, it’s done mechanically,” he said. “This option would be simple and quick.”

Druckenbrod said when a conventional greenhouse needs to be protected from sunlight, it is covered with a shading cloth or painted with whitewash. These methods are often long-term fixes that aren’t sensitive to changing weather conditions.

“A traditional greenhouse has a hard time constantly adjusting the light,” he said. “These panels can adjust throughout the day, even as a cloud passes, to instantly fog or clear the windows.”

The technology behind the greenhouse panels could be useful in other applications as well.

“I think it’s something potentially very promising in terms of commercialization,” said Oleg Lavrentovich, director of the Liquid Crystal Institute. “This is related to the more general concept of smart windows, not only for plants but also for people.”

Druckenbrod agreed.

“We use sunroofs and skylights and when we cover ourselves with glass, we’re often too hot or cold underneath it,” he said.

Both West and Lavrentovich said there will be opportunities for student involvement in the future. Lavrentovich said 30 graduate students are currently involved with the institute.

“(This project) provides a unique opportunity for research technology and education at the university,” West said.

How the technology works

Liquid crystals are rigid, rod-like molecules able to flow like liquid, John West, vice president for research and dean of graduate studies, said.

“They have the optical properties of diamonds but they’re fluid,” he said. “We can change the direction of the molecules with an electric charge and by doing that we change the optical properties.”

In a normal state, the liquid crystal molecules float randomly in polymer that is pressed between two pieces of glass. Light bounces off of them and only some is able to pass through the glass panel. At this point the panel resembles frosted glass. When an electrical charge is sent through the panel, the molecules line up in parallel fashion and allow all light to pass through. When this happens, the panel looks like a transparent glass window.

Liquid crystal panels can also be developed to allow certain wavelengths of light to pass through. The sun gives off ultraviolet, visible and infra red wavelengths. Infra red waves produce heat that is often unnecessary in the summer.

The panels could block infra red while allowing the other wavelengths to pass through. This would maintain a cooler temperature within the greenhouse while still providing the necessary lighting.

In the winter the panels would allow infra red to enter the greenhouse reducing the need for other means of heating.

– Source: Cleveland Botanical Garden press release.

Contact academic affairs reporter Kristine Gill at [email protected].