ASSESSMENT OF ENERGY CONSUMPTION IN GREENHOUSE PRODUCTION IN THE WEST REGION OF PORTUGAL

Greenhouse production is a very important activity in the West region of Portugal, with an area of approximately 800 ha where the regular production consists in two crops per year, one in winter-spring and the other in summer-autumn. Many growers are now prepared to better exploit market opportunities, since they know that the big export window opportunity is from June to September, when the production is difficult in other regions of south due to high temperatures. Grower’s use new and more productive varieties, either in soil or hydroponic systems, mostly in unheated greenhouses, naturally ventilated, and equipped with modern fertigation systems. Greenhouse production causes some environmental impacts due to the high use of inputs. Several improvements in technologies and crop practices may contribute to increase the use efficiency of resources, decreasing the negative environmental impacts. Greenhouse vegetable production in Northern EU countries is based on the supply of heating and differs significantly from the production system in the Southern EU countries. In the Northern countries, direct energy inputs, mostly for heating, are predominant while in the South the indirect energy input is also important, mainly associated with fertilizers, plastic cover materials and other auxiliary materials. The main objective of this work was to characterise the greenhouse production systems in the West region of Portugal, in order to evaluate the energetic consumptions (direct and indirect), the GHH emissions, the production costs and the farmer’s income. With this work the mostly important inputs were identified, allowing proposing alternative measures to improve efficiency and sustainability. All the data was obtained by surveys performed directly with growers, previously selected to be representative of the crop practices and greenhouse type of the region. However, more research should be performed in order to develop and to test technologies capable to improve resources use efficiency in greenhouse production

Energy consumption and greenhouse gas emissions of zucchini (Cucurbita pepo L.) cultivated in hydroponic greenhouses in the western region of Portugal

In recent years, there has been a significant increase in the consumption of zucchini (Cucurbita pepo L.) in Portugal, which has led to increased production of this vegetable. There is still a deficit of production in winter, but, in summer, production is higher than demand, allowing exportation. At present, there is a positive ratio between zucchini annual exportation/importation values. This means that it is an attractive crop for farmers, especially in the western region of Portugal, which has a microclimate favourable for this crop. The mild winter conditions of the region allow crop growth in unheated greenhouses, which is an advantage for reducing production costs and energy consumption compared with other regions. Crop productivity, either in soil or hydroponics, has increased through the use of better production techniques, modern fertigation systems and new and more productive cultivars. Several improvements in technology and crop practices may now contribute to increased resource-use efficiency, decreasing the negative environmental impact sometimes associated with greenhouse production. The main objective of this work was to evaluate the energy consumption (direct and indirect) and the greenhouse gas (GHG) emissions of greenhouse zucchini produced in the western region of Portugal. All the data were obtained through questionnaires performed directly with growers, which have been previously selected as representative of crop practices and greenhouse type in the region. The results show total energy consumption varying between 4.69 and 6.57 GJ t-1, the electricity used for irrigation making up the largest contribution, followed by the greenhouse material and fertilizers. With this work, the most important inputs were identified, allowing the proposal of alternative measures to improve efficiency and sustainabilit

Comparative studies on energy efficiency and GHG emissions between conventional and organic olive groves in Greece and Portugal

Nowadays, traditional farming based on achieving high yields using high inputs, shifts gradu-ally towards maximum possible crop yield using minimal inputs in an optimized way or to-wards organic farming. This is usually accomplishing by low yield of high quality products without using conventional agrochemicals (i.e. fertilizers, pesticides). In general, this last ap-proach leads to lower energy consumption per unit area of land, therefore lower cost and reduced greenhouse gas (GHG) emissions. However, in a global perspective it has the risk of significant total production reduction. Hence, it is vital to consider energy efficiency im-provement, namely the decrease of primary energy consumption for the production of a unit of agricultural product (expressed in weight or volume units), within the farm boundaries. Im-provement of energy efficiency is a key parameter affecting positively the overall efficiency of crop farming systems in terms of energy and GHG emissions. In the present paper, two show cases of olive groves in Greece (“Sterea Ellada” region) and Portugal (“Alentejo” re-gion) were compared to illustrate the effect on energy efficiency and GHG emissions when moving from conventional to organic olive grove cultivations in these different locations. The analysis was based on two simple framework models using information provided by farmers and literature data regarding the inputs and outputs of each olive grove. The models were adjusted according to the olives’ variety, the agricultural practices followed and the location of the production system. Considering the specific energy consumption per unit of product, in the case of the Greek olive grove, organic farming reduces energy consumption by 13.9%, while the final yield is reduced by 30%. GHG emissions are reduced by 58%. In the case of the Portuguese olive grove, organic farming significantly reduces crop yield (54.5%), while, energy efficiency is improved by 9.7% and GHG emissions are reduced by 26%

Energia, ambiente, economia e olival no Alentejo. Estudo preliminar

Prevê-se que o consumo de energia na agricultura irá aumentar significativamente nos próximos anos com a intensificação dos sistemas de produção. As melhorias na eficiência energética dos sistemas de produção estão relacionadas com a redução do uso de energia para um determinado serviço ou nível de actividade, ou a um aumento de produtividade para a mesma energia consumida. Os sistemas de produção agrícola estão muito dependentes de um consumo directo de energia (combustíveis), mas também de um consumo indirecto devido à energia gasta na produção de diversos factores de produção. Uma correcta avaliação de consumos energéticos deve considerar estas duas componentes. Neste trabalho analisaram-se 3 sistemas de produção do Olival (tradicional, intensivo e super-intensivo), uma das culturas mais importantes em Portugal. Para cada sistema de produção, calcularam-se os custos de capital e de operação das diferentes actividades, assim como os consumos energéticos (directos e indirectos) e o nível de emissões de gás com efeito estufa (GHG) traduzido em CO2eq. Verificou-se um acréscimo significativo de energia consumida, de produção de GHG e custos totais com a intensificação da produção. Mas também um aumento significativo da produção o que conduziu a um maior lucro para o agricultor. O sucesso da actividade agrícola está dependente do lucro, pelo que nesta cultura a tendência será caminhar para a intensificação. Deste modo será difícil diminuir o consumo de energia associado à produção do olival, mas será necessário aumentar a sua eficiência de utilização. Dado o elevado grau de mecanização dos sistemas intensivos, o aumento da eficiência energética na produção de azeitona no Alentejo terá de passar pela melhoria nas práticas de gestão culturais, no sentido de optimizar o uso das máquinas que lhes estão associadas. Ou ainda pela utilização de técnicas de agricultura de precisão numa tentativa de reduzir e optimizar a utilização de diferentes factores de produção, entre outras potenciais alternativas

Energy efficiency in agriculture

One of the EU headline target indicators for Europe is “20% increase in energy efficiency” by 2020. It is anticipated that in the following decades energy use will increase significantly and will have a widespread impact on the economy, including the agricultural sector. Energy use reduction can be achieved by reduced energy input. Improved energy efficiency, however, is only achieved, if energy input per unit yield is reduced. Therefore, improved energy efficiency can be realized with either increased or decreased energy inputs depending on the input-output relationship. In agricultural production the need for energy as an input can determine the profitability of farming which, in turn, impacts heavily upon the farmers’ investment in improved farming systems. This paper presents some of the results obtained in the WP2 of the KBBE.2011.4-04 project “Energy Efficiency in Agriculture - AGREE” supported by the 7th Framework Program. It gives an overview into energy use and energy efficiency of agriculture in various agro-climatic zones of Europe

Energy efficiency in olive oil mills

The paper presents some statistical data from olive oil mills in Portugal and Spain, presents the TESLA project and gives some information about energy consumption in olive oil mills

Energy efficiency in agriculture. Showcase and alternatives for wheat production in Portugal.

This chapter presents some results obtained in the KBBE.2011.4-04 project “Energy Efficiency in Agriculture - AGREE” supported by the 7th Framework Program. It gives an overview into energy use and energy efficiency in wheat production in various agro-climatic zones of Europe. Among cereals, wheat is the crop with the largest cultivated area in Europe. In 2008, the percentage share of the area occupied by common and durum wheat in the countries analysed in the AGREE project ranged from 2.4% in Portugal to 18.9% in Germany (Gołaszewski et al., 2012). The different production systems in different climates vary substantially in their energy use and energy saving potential. A showcase of conventional wheat production in Portugal, where in 2012 it was cultivated in 54,761 ha (INE, 2013), is presented and some production alternatives are analysed. The main objective was to analyse the effect in the economic results, energy consumption and environmental impacts of three wheat production systems alternatives: 1. no tillage cropping systems, 2. reduction of phosphorous application and 3. the use of supplemental irrigation

Economic and environmental analysis of energy efficiency measures in agriculture. Case Studies and trade offs.

This report is the result of the collaboration of the partners of the AGREE work-package “Economic and environmental analysis”, which is based on case study analyses of the partners in seven countries of the EU. The case studies show economic and environmental trade-offs in the different regions in the EU, for which each partner is responsible. Nevertheless prior to the reporting of the case studies an intensive discussion on a common methodological approach has been accomplished and applied to the case studies. The case studies show a wide range of different perspectives of energy efficiency in agriculture, but they are all based on the common methodology presented in Chapter 3. In Chapter 4, the case studies are presented, with authors indicated at the beginning of each section. Each section of Chapter 4 ends with a synthesis analysis of the results from the different case studies. Chapter 5 summarizes and concludes the report by highlighting the major findings of the analyses. The report builds upon the “State of the Art in Energy Efficiency in Europe” published separately by the AGREE consortium (Gołaszewski et al. 2012), which shows the status quo of energy use and possible energy efficiency measures in agriculture across different production systems and regions in Europe. This report presents an economic and environmental analysis based on in-depth case studies which show the potential for, and constraints on, energy efficiency measures in agriculture with respect to the specific environments in Europe

Manual de eficiência energética em Lagares

Este manual compreende uma análise do sector de produção de azeite em 4 países europeus, das metodologias de produção e uma análise dos consumos de energia durante o processo de produção. Contém ainda uma descrição de várias medidas para aumentar a eficiência energética nos lagares de azeite

Evaluation of energy consumption in intensive and super-intensive olive groves

O aumento da eficiência energética é um desafio que se coloca actualmente como contributo para a conservação do ambiente e dos recursos naturais. A utilização mais eficiente da energia significa obter maior produtividade por unidade de energia consumida. Tal é possível de duas formas, reduzindo o consumo de energia ou aumentando a produção. A avaliação do consumo de energia na agricultura tem-se centrado principalmente nos consumos de energia directa, mas neste trabalho mostramos que uma parte muito importante da energia total consumida nas explorações está relacionada com a energia indirecta, como p.e. a energia utilizada na produção de fertilizantes e outros factores de produção. Foi recolhida informação de quatro olivais em sistema intensivo e dois em sistema super-intensivo e foram estimados indicadores que permitem avaliar os consumos de energia directa e indirecta, que permitiram identificar quais os factores de produção com maior impacto do ponto de vista energético e ambiental. Os fertilizantes são um factor de produção muito importante no que ao consumo de energia diz respeito, seguido do gasóleo utilizado para as diferentes operações culturais. Os maiores consumos de energia, em todas as explorações, relacionaram-se com a utilização de fertilizantes. Os resultados obtidos parecem indicar que para melhorar a eficiência energética na produção do olival será fundamental investir numa utilização racional dos fertilizantes. Para tal, será necessário ter programas de fertilização perfeitamente adaptados ao sistema de produção, à variedade, ao estado fenológico da cultura e às características do solo, entre outros aspectos