Features Heating Structures & Equipment
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.

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 Internet at: www.ars.usda.gov/services/software/download.htm?softwareid=108.

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

Frantz,
Locke and Krause are adding 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 labour,
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.
The full feature is available at www.ars.usda.gov/is/AR/archive/may07/plants0507.htm.

Don Comis is a communications specialist with ARS, the U.S. Department of Agriculture’s chief scientific research agency.