Hybrid Renewable Energy System for Controlled Environment Agriculture

Abstract

With the expected impact of climate change and the projected population growth, the availability of sweet water and arable land will become increasingly scarce and the production from traditional agriculture processes will become insufficient to sustain the population. Controlled environmental agriculture (CEA) greenhouses represent a possible approach to deal with the challenges in the agricultural sector. The main advantages are the saving of water and the good production yield, even in inappropriate climatic conditions or arid regions. However, the production of agricultural greenhouse crops is an energy-intensive process that mostly relies on conventional energy sources contributing to the environment degradation and global warming. Therefore, a sustainable and environmentally friendly way to power the agricultural sector is needed to optimize sustainability in food production.This thesis contributes to these challenges by providing a techno-economic analysis, using HOMER (Hybrid Optimization Model for Multiple Energy Resources), of a hybrid stand-alone system to power a LED-lighted Closed-loop Greenhouse (LCG) located in a farm in Morocco. An assessment of the available resources at the selected location has been performed, followed by a technology assessment. Then, a hybrid system configuration has been designed for a stand-alone system. To observe the potential economic and technical impact, a comparison has been made between a fully stand-alone system and a similar system which has the option to sell excess electricity to the grid.The resulting hybrid system configuration in both analyses is composed of photovoltaics panels, batteries and a biogas engine, using locally produced biogas, as a backup. The stand-alone system has a Levelized Cost of Electricity (LCOE) of 0.203 €/ kWh. This price is higher than the current grid rate of 0.15 €/ kWh, which means it is not competitive if the grid is available. On the other hand, the system that can sell back the excess of electricity to the grid at an assumed price of 0.05 €/ kWh, the LCOE obtained is 0.126 €/ kWh; which is lower than the current grid price and therefore competitive if the grid is available. Finally, this thesis provides a sustainability analysis focused into the economic, social and environmental dimensions.