Climate control & energy > Introduction
Energy
Greenhouses utilise the sun as the main energy source, but they also require a lot of energy (fuel) for maintaining optimal growing conditions. Energy consumption has to be reduced as part of the world-wide strive to reduce carbon emission and global warming.
Heating
The major portion of fuel consumption for greenhouse control is used for heating, to control both temperature and humidity. Fuel can be used for CO2 enrichment, and for driving a CHP unit (combined heat and power). Greenhouses also use energy in the form of electricity to run pumps, engines, and much more. In this website we focus on energy used for greenhouse heating (in fact for greenhouse climate control), since this is often by far the largest part of the energy use.
Improving energy efficiency
Energy can be the largest single cost factors for a greenhouse grower. Increasing fuel costs stimulate growers to reduce energy input. However, it is important to maintain the same level of production in order to stay profitable. The aim is to enhance the energy efficiency (= get more production for the same energy input). There are many ways to improve the energy efficiency in greenhouses, some without making large investments. For instance, often huge energy saving can be achieved by improving the control of the greenhouse climate conditions, especially air humidity. Energy can be saved by repairing faults and leakages, by maintaining and servicing materials and equipment, and by improving the set-up and management of the production process.
Energy-efficient equipment
After taking the basic actions, growers can invest in energy saving technology such as insulation material, flue gas condensor, heat buffer, energy screen, better computer, renovating the greenhouse, replacing an inefficient boiler, installing a CHP unit. In some cases, new greenhouses can be built close to a power plant or industry to use their waste heat for greenhouse heating. Ideally, investments in energy saving technology will be earned back by reduced energy costs and possibly higher production. In some countries subsidies and tax incentives are available to help cover the costs of energy efficient investments.
Future
Drastic innovations for improving energy use in greenhouses are undertaken especially in the Netherlands. Special mention deserves the 'closed greenhouse', where energy from the sun is trapped in greenhouses in summer, and stored in the aquifer for use in winter.
Further reading
Energy saving measures – options listed (2003)
Calculating energy efficiency and carbon tax for greenhouses (2003)
'Green Label Greenhouse’ and energy-saving policies in the Netherlands (2004)
The costs of carbon tax for greenhouse growers (2005)
Energy tax and CO2 emission rights in the
Potential energy saving measures categorised (2006)
Energy study completed opportunities assessed (2007)
See menu on the left to find articles on specific topics.
