Commentary: Night lighting fields for food
Announcement of research findings about artificial light, such as that used to grow crops in greenhouses, could mean considerably greater production in greenhouses, and who is to say that artificial light research findings in the future might not allow growing crops in large-acreage lighted outdoor fields.
Enormous amounts of energy are wasted in greenhouses where our food is grown as a result of the plants receiving too much and the wrong kind of light. This can also stress and damage the plants, according to researchers at Chalmers University of Technology in Gothenburg, Sweden. These researchers are working on a globally unique method to measure how much and what type of light plants want and need.
Current greenhouses use what are known as high pressure sodium lamps, which are basically the same type of lamps that are used for street lights. The light spectrum provided by high pressure sodium lamps corresponds very poorly to the spectrum plants use during photosynthesis. Plants do not receive very much of the blue and red light that they need the most. They do, however, receive a great deal of infrared light, which is harmful to some crops, and yellow light, which the plants cannot utilize to any great extent.
The research project at Chalmers University aims to ascertain how much and what type of light different plants require at specific times. In the process of gathering data, a spectrometer is being used to measure which wavelengths are sent back by the plants—direct reflection and fluorescence.
The project's aim is to produce a system that employs the plants' response and automatically regulate the lights in the greenhouse for growing plants with the proper light for the specific plants being grown.
"Everything in modern greenhouses is very high tech except for lighting," says Anna-Maria Carstensen, who is a doctorate student in automatic control at Chalmers. "Temperature and nutrition are meticulously controlled. Lighting regulation, however, lags far behind."
Now, what happens as we look in the distant future when light and generating it has been investigated much more thoroughly? Could we have the energy necessary to generate specific light to aid plants to grow fast all night long on large fields? Could the same field produce three, four or more crops in one growing season?
The whole wild idea springs to my mind because of the Chalmers University research making strides and my recent tour of Iceland where extremely inexpensive geothermal electricity is generated and highways and streets are smothered in artificial light.
Generating enough light to cover whole fields seems possible after seeing a highway light about every 100 yards for much of the 30 to 40 minute drive from the international airport to the capitol city of Reykjavik.
It seems quite possible to me that 100-acre fields in the future could be lit at night to grow food crops.