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Reliable and quick assessment of energy conservation measures in greenhouse cultivation supports growers in their operations. Such an overview should quantify the consequences of changes in energy flows for total energy consumption, amount and quality of production, and farm economy.Using tomato as an example crop, comprehensive energy balances were developed for a reference situation in The Netherlands. Solar radiation, primary and secondary heating circuits and CO 2 from the flue gasses of the heating system were quantified as energy sources. Energy use for air and leaf temperature increase, crop photosynthesis, crop transpiration, as well as energy losses through the roof, walls and ground surface were quantified. Subsequently, the effects of 11 energy conservation measures were computed. Consequences for gas consumption and production were simulated with a greenhouse and a crop growth model, respectively, consequences for quality were assessed on the basis of expert knowledge, and economic consequences were simulated with a cost-benefit model.For tomato, most energy was saved by increased insulation of the greenhouse cover (23% saving) and lowered temperature set point (16%), followed by increased set point for air relative humidity, screen gap control in steps, and temperature integration (all about 5%). Fresh tomato production fell in most cases, except in case of increased light transmission by the greenhouse cover. Energy use efficiency was defined as the amount of energy required to produce a certain quantity of fresh harvestable product. Energy-conservation aims to decrease the energy use efficiency. Greatest gains were reached through insulation (-20%), lowered temperature set point (-12%) and improved light transmission (-8%). Improved light transmission resulted in the strongest increase of the balance of yield and costs (€2.6, or 10%), followed by increase of RH set point, crop-based RH control, crop-based use of the energy screen, increased size of the thermal storage tank and reduction of crop transpiration (all less than €0.5).Although energy conservation reduces fuel costs, its implementation depends on the effects on production an overall economic profitability of the farm. Improved roof insulation, reduced temperature set point, screen gap control in steps, increase of the RH set point, temperature integration, and crop-based RH control are first candidates for (further) implementation. Other measures require prior technological advancements or fine-tuning. INTRODUCTIONGiven the high costs of energy and obligations imposed on national governments by the Kyoto protocol (UNFCCC, 1997), energy conservation in horticulture has become increasingly important. Reliable and quick assessment of measures to conserve energy supports growers in their operations, and policy makers in directing research funds. Energy conservation assessments require an overview of the most important energy flows and their consequences. Changes in energy flows may have consequences for the

In dit rapport presenteren we een effectbeoordeling van zes doelstellingen van de Farm to Fork-en biodiversiteitsstrategieën met betrekking tot vermindering van het gebruik en risico van pesticiden, vermindering van nutriëntenverliezen, vergroting van het areaal in de EU waarop biologische productie plaatsvindt en verhoging van de hoeveelheid land dat bestaat uit landschapselementen met grote diversiteit. Er zijn vier scenario's ontwikkeld waarvan de effecten zijn beoordeeld: (1) vermindering van gebruik en risico van bestrijdingsmiddelen, (2) vermindering van gebruik en verlies van nutriënten (3) vergroting van het biologische areaal en (4) een combinatie van de scenario's 1 en 2 uitgebreid met de doelstelling om meer land met landschapselementen met grote diversiteit te hebben. De effectbeoordeling is uitgevoerd op bedrijfsniveau en heeft betrekking op tien gewassen en zeven caselanden in de hele EU. Met de resultaten van de casestudies is onderzocht wat de gevolgen zijn van deze doelstellingen voor het productievolume van de gewassen in de EU, de prijzen, de internationale handel en indirect landgebruik.In this report we present an Impact Assessment on six objectives of the Farm to Fork and Biodiversity strategies with respect to reduction of pesticide use and risk, reduction of nutrient losses, increase of the area in the EU under organic production and increase of the amount of agricultural land under high-diversity landscape features. Four scenarios have been developed for which the impacts have been assessed: (1) reduction of use and risk of pesticides, (2) reduction of use and losses of nutrients, (3) increase of area under organic production and (4) a combination of the Scenarios 1 and 2 extended with the added objective to have more land with high-diversity landscape features. The impact assessment has been executed at farm level, covering ten crops and seven case countries across the EU. The results of the case studies have been used to explore the consequences of these objectives for the production volume of the crops in the EU, market prices, the international trade and indirect land use.

This environmental impact assessment of the current situation of Dutch tomato production in a Venlo greenhouse in a temperate climate was developed as part of the EUPHOROS project. The project aims to develop a more sustainable greenhouse system with a reduction of external inputs yet with high productivity and an efficient use of resources. The environmental impact analysis was based on using the Life Cycle Assessment (LCA) methodology as defined by the ISO 14040. The crop production system was structured in several stages and processes to facilitate the study and interpretation of results. The stages considered were structure, auxiliary equipment, climate control system, fertilizers, pesticides and waste. The main results and issues to be improved are described and presented in this paper. The use of a cogeneration system (CHP) and the consequent production of electricity create a methodological question on how to handle allocation between products. This paper shows two different methods for dealing with co-production: considering electricity as an avoided product and energy allocation at CHP. Depending on the approach considered values can range between 12 to 31 MJ/kg of tomato or 0.78 to 2.0 kg CO 2 eq/kg of tomato for instance. Climate control system had a high energy demand with major contributions to all the impact categories (81.1 to 96.1% of the total) and the rockwool substrate accounted for 57.0 to 81.7% of the auxiliary equipment contribution. More effort should be made to recycle rockwool and reduce the high energy demand associated with the expansion of the mineral in the manufacturing processes. The structure was a major burden due to the high amount of steel and glass. Energy environmental impacts could be reduced, because of the avoided electricity production by the power plant, by using a combined heat and power plant to meet greenhouse electricity demands, resulting in a surplus which could be delivered to the public grid. Further research should also be oriented to developing efficient technologies to improve the intensive use of materials and energy.