Building and Heating a Virtual Greenhouse

Growers can now build and heat a "virtual" greenhouse—or upgrade existing greenhouses—on a computer, to find out how much it would cost to heat with different fuels, heating schedules, heaters, building designs and materials.

Agricultural Research Service (ARS) plant pathologist Jim Locke, horticulturist Jonathan Frantz and research leader Charles Krause have published this "Virtual Grower" software on the World Wide Web at:

/services/
software/download.htm?softwareid=108

They are part of the ARS Greenhouse Production Research Group at Toledo, Ohio.

Soon Frantz, Locke and Krause will add a plant component to the computer program so growers can see the effects of their heating choices and schedules not only on costs, but also on their plants. They'll gradually expand the software to include all other aspects of greenhouse management, including applications of nutrients, water, growth regulators and pesticides. Ultimately, it will also help growers manage labor, optimize plant productivity and set sale prices. There are many individual programs like this, but none that considers all of these factors interacting together, as this one eventually will.

To estimate energy requirements and costs using Virtual Grower, users input the dimensions of their greenhouse and its construction materials, such as poured-concrete floor, glass sides and roof, or concrete-block walls. They also choose design features, such as roof shape and orientation to the sun. A historical database gives a year's worth of typical weather for the city nearest to the greenhouse location—including factors such as temperature, sunlight and cloud cover—for each hour of the day.

Growers choose a heating schedule and set the temperatures they want to maintain during day and night, or for each hour. The program then calculates per-square-foot heating costs by the month or year.

Since Virtual Grower is a work in progress, growers are invited to e-mail questions or suggestions to help Frantz, Locke and Krause fine-tune this tool for managing greenhouses for greater productivity at lower costs.

ARS is the U.S. Department of Agriculture's chief scientific research agency.