Science - January 7, 2011

Horticulture can achieve climate goal

Dutch market gardeners use energy much more efficiently today than twenty years ago. Besides saving on gas usage, their CHP installations also produce ten percent of the country's electricity needs, according to research done by LEI.

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Greenhouses used 53 percent less fuel to produce one kilogramme of vegetables and flowers in 2009 than in 1990. As such, market gardeners are only four percent away from the aims of the 'Agroconvenant' - an agreement between the government and the farming sector - which aims for a 57 percent reduction per product unit in 2020. This saving in energy has brought the CO 2 emission down by 1.5 megatonnes to 5.3 megatonnes. With this, the market gardeners have already achieved the climate goal set for 2020. Actual energy savings are in fact much lower - much more vegetables and flowers are now produced with less energy than twenty years ago.
CHP
Market gardeners use gas to heat their greenhouses. Better insulation and closed greenhouse systems enable them to use much less energy than before. Moreover, they also produce electricity, as well as heat, in their combined heat and power (CHP) installations. These installations together account for ten percent of the country's electricity production, and are much more efficient than the average energy stations in the Netherlands. The CHP installations produce 1.7 megatonnes of CO 2 but they replace electricity from electricity stations which produce 2.2 megatonnes. As such, the horticulture sector has reduced total CO 2 emission in the Netherlands, besides producing more electricity than it uses.
Solar heating
Another objective of the Agroconvenant, i.e. to replace natural gas with sustainable energy in horticulture, however, has still a long way to go before it can be achieved. Solar heating, biofuels, geothermal heating and purchases of sustainable heating in 2009 amounted to only 1.3 percent. The agreement has targeted 4 percent in 2010 and 20 percent in 2020. Market gardeners take advantage of the low tax rates imposed on natural gas. They pay lower energy taxes than Dutch households, just like other energy-intensive sectors.