Energy saving: from engineering to crop management

In greenhouse horticulture, energy costs form an increasingly larger part of the total production costs. Energy is primarily used for temperature control, reduction of air humidity, increase of light intensity and CO2 supply. Use of fossil energy can be reduced by limiting the energy demand of the system and decreasing energy losses, by intelligent climate control, by increasing the energy efficiency of the crop and by replacing fossil energy sources by sustainable ones. Energy requirement of the greenhouse can be lowered up to 20-30% by using greenhouse covers with higher insulating values and the use of energy screens. A prerequisite is that these materials should not involve considerable light loss, since this would result in a loss of production. In energy efficient greenhouse concepts, durable energy sources should be included. In (semi-)closed greenhouses, the excess of solar energy in summer is collected and stored in aquifers to be reused in winter to heat the greenhouse. Ventilation windows are closed, with specific benefits to the crop: high CO2 levels can be maintained, and temperature and humidity can be controlled to the needs of the crop. Development of new greenhouse concepts is ongoing. Current examples are greenhouse systems which convert natural energy sources such as solar energy into high-value energy such as electricity. Given a certain technical infrastructure of the greenhouse, energy consumption can be further reduced by energy efficient climate control and crop management. Essential elements are to allow fluctuating temperatures, lower crop transpiration, allow higher humidities, make efficient use of light and create fluent transitions in set points. Consequences for plant growth are related to rate of development, photosynthesis, assimilate distribution, transpiration and the occurrence of diseases or disorders. Since processes involved are complex, knowledge exchange between researchers and growers is essential to realize the goals set to reduce the energy consumption.

[1]  T. A. Dueck,et al.  FILTERING NATURAL LIGHT AT THE GREENHOUSE COVERING - BETTER GREENHOUSE CLIMATE AND HIGHER PRODUCTION BY FILTERING OUT NIR? , 2006 .

[2]  Roar Moe,et al.  Effect of diurnal temperature alternations on plant morphology in some greenhouse crops. A mini review , 1995 .

[3]  H. Challa,et al.  The solar greenhouse: state of the art in energy saving and sustainable energy supply. , 2005 .

[4]  M. I. Sysoeva,et al.  Temperature drop, dry matter accumulation and cold resistance of young cucumber plants , 1999, Plant Growth Regulation.

[5]  S. Hemming,et al.  Greenhouse cooling by NIR-reflection , 2006 .

[6]  G. Bot,et al.  The Solar Greenhouse ; Technology for Low Energy Consumption , 2003 .

[7]  Frank Kempkes,et al.  Mechanically controlled moisture removal from greenhouses , 2009 .

[8]  E. Heuvelink,et al.  Climate and Yield in a closed greenhouse , 2008 .

[9]  A. de Gelder,et al.  CLOSED GREENHOUSE: A STARTING POINT FOR SUSTAINABLE ENTREPRENEURSHIP IN HORTICULTURE , 2005 .

[10]  V. M. Valdés,et al.  The effects of leaf removal and of modifying temperature set-points with solar radiation on tomato yields , 2002 .

[11]  T. A. Dueck,et al.  Diffuse greenhouse covering materials material technology, measurements and evaluation of optical properties , 2008 .

[12]  H. F. de Zwart,et al.  Dehumidification of Greenhouses at Northern Latitudes , 2003 .

[13]  Ep Heuvelink,et al.  Quantification of temperature, CO2, and light effects on crop photosynthesis as a basis for model-based greenhouse climate control , 2009 .

[14]  Silke Hemming,et al.  New glass coatings for high insulating greenhouses without light losses - energy saving crop production and economic potentials , 2011 .

[15]  Eva Rosenqvist,et al.  INTELLIGROW: A COMPONENT-BASED CLIMATE CONTROL SYSTEM FOR DECREASING GREENHOUSE ENERGY CONSUMPTION , 1999 .

[16]  C. Stanghellini,et al.  Transpiration of greenhouse crops : an aid to climate management , 1987 .

[17]  R. G. Hurd,et al.  THE INFLUENCE OF DIFFERENT TEMPERATURE PATTERNS HAVING THE SAME INTEGRAL ON THE EARLINESS AND YIELD OF TOMATOES , 1984 .

[18]  J. C. Bakker,et al.  The effects of diurnal temperature regimes on growth and yield of glasshouse sweet pepper. , 1988 .

[19]  T. Boulard,et al.  Innovative technologies for an efficient use of energy , 2008 .

[20]  P. Jaster,et al.  ENVIRONMENTAL CONDITIONS UNDER AN EXPERIMENTAL NEAR INFRA-RED REFLECTING GREENHOUSE FILM , 2002 .

[21]  Janneke A. Dieleman,et al.  Energy screens in tomato: determining the optimal opening strategy , 2006 .

[22]  S. Hemming,et al.  The Effect of Diffuse Light on Crops , 2008 .

[23]  S. Adams,et al.  Effect of Temperature on the Growth and Development of Tomato Fruits , 2001 .

[24]  N. J. van de Braak,et al.  THE ENERGY BALANCE AND ENERGY-SAVING MEASURES IN GREENHOUSE TOMATO CULTIVATION , 2005 .

[25]  Gert-Jan Swinkels,et al.  Greenhouse with an Integrated NIR Filter and a Solar Cooling System , 2006 .

[26]  Barbara J. Regeer,et al.  TransFormers in knowledge production: building science–practice collaborations , 2008 .

[27]  H. Challa,et al.  Effect of electrical conductivity and transpiration on production of greenhouse tomato (Lycopersicon esculentum L. ) , 2001 .

[28]  J. C. Bakker,et al.  Greenhouse cooling and heat recovery using fine wire heat exchangers in a closed pot plant greenhouse: design of an energy producing greenhouse , 2006 .

[29]  T. A. Dueck,et al.  Efficiency of light energy used by leaves situated in different levels of a sweet pepper canopy , 2006 .

[30]  H. F. de Zwart.  The sunergy greenhouse - one yer of measurements in a next generation greenhouse , 2011 .

[31]  A. de Gelder,et al.  The photosynthesis response of tomato to air circulation , 2007 .

[32]  N.J.A. van der Velden,et al.  Energiemonitor van de Nederlandse glastuinbouw 2000-2006 , 2007 .

[33]  R. Grange,et al.  A review of the effects of atmospheric humidity on the growth of horticultural crops , 1987 .

[34]  H. F. de Zwart,et al.  Exchange of Knowledge between Research and Horticultural Practice through the Internet , 2008 .

[35]  A. de Gelder,et al.  Comparison of climate and production in closed, semi-closed and open greenhouses , 2011 .

[36]  S. Grimstad,et al.  The effect of a daily low temperature pulse on growth and development of greenhouse cucumber and tomato plants during propagation , 1993 .

[37]  J. H. M. Thornley,et al.  Temperature and CO2Responses of Leaf and Canopy Photosynthesis: a Clarification using the Non-rectangular Hyperbola Model of Photosynthesis , 1998 .

[38]  Gert-Jan Swinkels,et al.  Conversion of NIR‐radiation to Electric Power in a Solar Greenhouse , 2007 .

[39]  F. Buwalda,et al.  AN ENERGY EFFICIENT HEATING STRATEGY FOR CUT ROSE PRODUCTION BASED ON CROP TOLERANCE TO TEMPERATURE FLUCTUATIONS , 1999 .

[40]  K. Verkerk,et al.  Temperature, light and the tomato , 1955 .

[41]  Silke Hemming,et al.  Cover materials excluding near infrared radiation: effect on greenhouse climate and plant processes , 2008 .