Cogeneration Economics for Greenhouses in Europe

Abstract

<jats:p>Cogeneration is a cost-effective technology, and modern greenhouses are considered one of the best applications for it due to their energy intensity. Taking into account that in such cases the production cost is significantly affected by the cost of energy, the potential of combined heat and power (CHP) has already been examined and proved in practice in some European countries, with the Netherlands being the most representative example. In this study, a comparative investigation of the greenhouse energy cost in all European countries is presented through the use of a combined cooling heat and power (CCHP) system. Using actual historical data spanning a decade, a total overview of the European level is given regarding greenhouse thermal requirements and CCHP energy costs for the cultivation of products with an accepted temperature cultivation range 20 ± 5 °C. By consulting (a) the available daily historical meteorological data for the 2008–2018 period, (b) the recorded actual electricity and natural gas prices for the 2008–2018 period, and (c) the technical characteristics of the CCHP system, the annual heating and cooling requirements of greenhouses are determined for all EU countries. Assuming a cogeneration unit with an internal combustion engine (ICE) as a prime mover, as well as a single-effect absorption chiller for the production of useful cooling, the unitary cost of energy is estimated along with the annual cost for heating and cooling per unit cultivation area. Using this methodology, the economic efficiency of cogeneration in greenhouses is assessed for the selected 10-year period, allowing the identification of the countries that benefit the most from this technology. The results indicate that the spark ratio (e.g., the electricity to natural gas price ratio) is the most crucial parameter for greenhouse costs. For countries where the ratio is larger than 3, greenhouses can even result in an extra cashflow instead of energy expenditures. The most favorable conditions for cogeneration use were found in Italy and the United Kingdom with an average spark ratio more than 4, resulting in an annual total cost of heating energy close to −7 €/m2 per year. On the other hand, cogeneration proved not to be a cost-efficient system in Sweden and Finland as a result of significantly high greenhouse energy requirements.</jats:p>

Cogeneration Economics

“…The first [1] analysed the long-term economic performance of some projects in the Mediterranean climate of Athens, Greece, while the second [2] focused on the short-term, detailed economic performance of a cogeneration system in a hospital. A third paper [3] modelled the performance of a cogeneration system in a greenhouse and evaluates its economic efficiency versus the European country and the kind of cultivation. The last paper [4] examined the economics of heat engines and heat pumps in recovering waste heat in oil refineries.…”

“…Engine Industry Method [1] Internal Combustion Engine Buildings Key Performance Indices, Real Data [2] Internal Combustion Engine Buildings Key Performance Indices, Real Data [3] Internal Combustion Engine Greenhouses Modelling, Statistical Data [4] Heat Engines, Heat Pumps Oil Refineries Modelling, Literature Data Since a few papers were submitted, limited topics were covered. However, the economics of cogeneration was revealed for some sectors such as buildings, greenhouses, and oil refineries.…”

“…Cogeneration Economics for Greenhouses in Europe [3] Cogeneration is a cost-effective technology, and modern greenhouses are considered one of the best applications for it due to their energy intensity. Considering that in such cases the production cost is significantly affected by the cost of energy, the potential of combined heat and power (CHP) has already been examined and proved in practice in some European countries, with the Netherlands being the most representative example.…”

Model Predictive Control versus Traditional Relay Control in a High Energy Efficiency Greenhouse

“…Heating and cooling costs seriously affect the economic profits but, in the long term, may also limit a large diffusion of the greenhouse cultivations. In general, energy costs account for up to 40% of final production costs in a greenhouse [32]. Moreover, high-energy consumption heating systems may generate the emission of noxious gases that produce environmental problems.…”

Application of Distributed Electricity Generation Systems in Agricultural Greenhouses

“…Tataraki, et al [17], have studied the CHP economics for greenhouses in Europe. The authors mentioned that co-generation is a cost-effective technology and modern greenhouses are considered one of the best applications for it due to their high energy intensity.…”