Research explores full spectrum lighting for horticulture

Lighting plays an increasing role in horticulture, both for urban farming, for cultivation without daylight and increasingly also in greenhouses. Until now the focus has mainly been on higher production through the use of light. However, apart from the focus on crop yield there has not yet been any detailed research and investigations into the effects that light spectrum has on crop growth, quality, taste and seed production. The research project will study the growth of a variety of plants under four different light sources and will record six attributes of plant growth. This will include how the plant forms and how it is cultivated, for example, whether it becomes a more compact crop. Plant quality will be analysed including sugar content, acidity, firmness and shelf life. Investigation into the plant roots will also be conducted since a better root system leads to better crop growth. For many crops, the flowers and fruits are key aspects of achieving not only a better crop but a more controllable yield so monitoring this as part of the cultivation process will also take place.

Today there are a number of different lighting technologies used for horticulture applications such as high-pressure sodium (SON-T) and LED. However, Light Emitting Plasma (LEP) lamps, driven by an RF power source, provide a full spectrum of light and is believed to offer much better value to growers.

J. den Besten, Senior Lecturer New Cultivation Systems, HAS University of Applied Sciences, commented: "This research gives us a unique opportunity to conduct a broad exploration of the opportunities and possibilities of illuminating a greenhouse with full spectrum lighting. The study provides a basis for a route whereby we not only use light for increased production but look at the overall value to the grower."

Ampleon are sponsoring a 20 week research programme that started in late 2015 based in the University’s newly opened glasshouses and research facilities. The research will investigate the different aspects of growing a variety of crops under full spectrum LEP lights together with making comparisons against using LED, High Pressure Sodium SON-T, Ceramic Discharge Metal-halide (CDM) lighting.

Rob Hoeben, Vice President & Business Unit Manager Multi Market & RF Energy, Ampleon, commented: “We are delighted to be collaborating with HAS University of Applied Sciences on what we believe to be the first comprehensive research project into growing crops under full spectrum lighting. The use of our RF power semiconductors for full spectrum plasma lighting is an exciting new area for us and we look forward to receiving the results during early 2016.”