This is what climate protection looks like

High energy efficiency, lower costs

A queen with a conscience




Against the backdrop of rising energy costs and the ongoing debate about CO2 emissions, companies that squander energy will probably have a hard job staying in the market. Energy will account for an increasing share of the overall costs of running a greenhouse. Growing orchids consumes a great deal of energy, so orchid-growers keep a keen eye on costs. That's why more and more greenhouses, especially in the Netherlands, are glazed with PLEXIGLAS? because its excellent heat insulation offers significant benefits.

Grace, purity, elegance and beauty are the attributes of a queen. So it's no wonder orchids are seen as the aristocrats of pot plants. They also call for right royal treatment during their cultivation. Lavishly tended, nurtured and checked, they feel happiest at 27 degrees Celsius.

Not exactly the average temperature in the Netherlands, the world's largest supplier of orchids. To thrive in Europe, these tropical plants are raised under artificial conditions of heat and humidity. That makes them real energy fiends. Good heat insulation and energy conservation have long been particularly important in this branch of industry, and call for efficient glazing. Double glazing with U-values of less than 3W/m?K should be the rule.

Many growers rely on PLEXIGLAS? to keep heating costs down to an acceptable level. "It transmits more light than other materials, insulates better than conventional single glazing and therefore saves energy. It's also highly resistant," explains Michael Haussmann, responsible for the greenhouse market in Evonik's Acrylic Sheet Business Line.

Double-skin sheets for pot plants

Growers of pot plants in particular opt for energy-saving, light-transmitting PLEXIGLAS? when it comes to converting existing greenhouses or building new ones. The insulating air cushions in the double or triple-skin sheets offer particularly high thermal resistance and are therefore more suitable than single glazing. The more layers of air, the better the heat insulation. Greenhouses are normally built with two skins at most, to retain the highest possible light transmission.

These facts also convinced Arjen Peerdeman, an orchid grower from Zaagdijk-Oost. This cost-conscious and environment-minded operation chose PLEXIGLAS ALLTOP? SDP as the economical solution to energy consumption in greenhouses. "Not only do plants flower better thanks to the UV transmission of PLEXIGLAS ALLTOP? SDP, the air cushions in the double-skin sheets help us save energy. That means I can do my bit for the environment and get better results at the same time. PLEXIGLAS ALLTOP? SDP has convinced us, and that is why we are presently adding another 6,800 square metres of greenhouse capacity."

"The Netherlands are our most important market at present, and one the whole world is watching. A total greenhouse area of 200 hectares are glazed with PLEXIGLAS? in the Netherlands. This is where trends are set," Michael Haussmann says. "The crucial factor is that we can provide these leading global plant specialists with exactly what their plants need."

For Eric Moor, that means PLEXIGLAS RESIST? double-skin sheet. The Dutch horticulturalist produces flowering Phalaenopsis orchids in Europe's most modern greenhouse. His colleagues, who grow Phalaenopsis seedlings, have slightly different requirements and therefore depend on PLEXIGLAS ALLTOP? SDP. These sheets transmit UV light and let the entire solar spectrum into the greenhouse.

Kees Schoone has 60,000 square metres of ultramodern production space at his disposal at Floricultura in the Dutch town of Heemskerk. Energy conservation was what prompted him to choose PLEXIGLAS ALLTOP? double-skin sheets. "I save about 40 per cent in energy costs as compared with traditional single-glazed greenhouses," he reckons. This figure is confirmed by the Institute of Agricultural and Environmental Engineering (IMAG-DLO), which established that energy savings of 24 to 55 per cent can be achieved using PLEXIGLAS ALLTOP? , depending on sheet thickness. "The UV transmission also has a positive effect on seedling growth. So we are investing in vigorous growth and energy saving," says Kees Schoone, whose business grows some 30 million orchids per year.

The same applies to the Phalaenopsis orchid "nursery" of specialist Ed Meeuwissen at Orchids4ALL in Aalsmeer near Amsterdam. The greenhouses built there in 2001 by greenhouse specialist Bosman using PLEXIGLAS ALLTOP? SDP have now been extended to 25,000 square metres.

Scandinavia and North America are catching up

"PLEXIGLAS? is not just the trend in the Netherlands - Scandinavian countries and North America are catching up," Haussmann says. But there are climatic differences that influence the choice of material. Andy Matsui in Salinas Valley, California, chose PLEXIGLAS RESIST? SDP in 8mm thickness. That is important because California is very hot in the daytime, but cool at night, so the temperature deficit has to be balanced and the heat level kept constant.
America's largest grower of potted orchids is presently expanding again. The Matsui Nursery is glazing a further 15,000 square metres of greenhouse with PLEXIGLAS RESIST? SDP 8, bringing the total area glazed with PLEXIGLAS? to 50,000 square metres. Matsui also began several years ago to refit his older greenhouses successively with the long-lasting eight-millimetre-thick double-skin sheets. His total greenhouse capacity is an impressive 30 hectares. "The 21st century belongs to the orchid," Matsui says. He expects the demand for orchids to grow steadily.

The greenhouse of the future

Orchids are not the only pot plants and ornamental varieties to thrive under PLEXIGLAS?, which is often chosen to cut energy costs. "There is clearly a trend towards the low-energy greenhouse, and the Netherlands plays a pioneering role, with plans for greenhouses that can be heated completely without fossil fuels," Michael Haussmann tells us.  


The story about the queen of pot plants is just one of the articles in the current issue of the Greenhouse Journal: PROFITABLE GROWTH UNDER ACRYLIC. Download PDF  

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