Energy-saving Greenhouse

The Cleveland Botanical Garden and Kent State University's Liquid Crystal Institute (LCI) have unveiled a new research project to explore the use of liquid crystal panels to create energy-efficient greenhouses.  Two 8x10' greenhouses have been constructed at the botanical garden -- one with plain glass panels and the other with liquid crystal panels. Over the next several years, researchers will compare plant growth, temperature, light levels, and energy used in each greenhouse.

The Cleveland Botanical Garden's executive director, Natalie Ronayne, says the basic goal is "to design a smart greenhouse."  She explained that the liquid crystal panels can regulate the amount of sunlight reaching plants inside.  The LCD greenhouse has a photo receptor inside that can be programmed for specific plants, according to the amount of light they need. "If you program it to have a certain amount of light and it's a cloudy day, the windows will never become foggy -- they will stay fully on to attract and absorb as much light as possible from the spectrum," said Ronayne. "If it's really sunny and it's a hot day ... the windows will automatically dim to control the shading."

The experimental greenhouses house a variety of plants -- tomatoes, peppers, petunias, lilies, orchids, and more. Ronayne said the experiment will last for at least two years -- to measure plant growth, monitor energy bills, and test the durability of the LCD windows.

The hope is that by controlling the amount of light coming into the greenhouse, costs for heating and cooling major greenhouses will be reduced. 

The Cleveland Botanical Garden in 2003 opened an 18,000 square foot glass conservatory that houses exhibits on two of the world's endangered ecosystems -- the Costa Rican cloud forest and the spiny desert of Madagascar.

The project came about when the garden began exploring ways to promote energy efficiency, and a local advocate of fuel cell technology suggested that the garden get in touch with Kent State's LCI.  According to Ronayne, the experiment at the botanical garden is the first that is testing liquid crystal panels in an exterior application.

Dr. John West, vice president for Research and dean of Graduate Studies at Kent State, said there is great potential for "spin-off industries and technology."  The garden believes that the development of sustainable greenhouses adaptable to different climates and regions could boost Ohio's existing "green" industries -- floriculture, nursery and landscape -- and contribute to a more sustainable world.