Techno-economic-environmental analysis of solar/hybrid/storage for vertical farming system: A case study, Malaysia

Abstract

Human population is projected to reach 9.7 billion in 2050 and strike 11.2 billion by 2100. Residence shift from countryside to cities will occur and the human population resides in the cities is envisaged to rise from 55% to 68%. Vertical farming was proposed to address food insecurity caused by overcrowded population and farmland shortages. The compound annual growth rate (CAGR) of vertical farming in the Asia Pacific is forecasted to grow at 22.1% with a market size reaching USD 2,101.0 million by 2024. Malaysian government encourages the implementation of vertical farming as the production of major agricultural commodities has contracted by 3.4% from 2015 to 2017. However, high energy consumption is one of the shortcomings of a vertical farm as the estimated annual energy consumption for each square meter of growing area is 3500 kW h. Thus, this paper proposes an optimized building geometry modeling integrated with energy yield estimation tool to evaluate the potential of integrating green energy into urban agriculture. This research examines the load demand in the vertical farming systems and develops solar/hybrid/storage for vertical farming system with energy yield, performance ratio, economics and environmental assessments. Preliminary resources assessment by analyzing the solar radiation of the sites was carried out at stage 1. At stage 2, load consumption was calculated, and specifications of the system were justified. Stage 3 included the development of solar PV system for the vertical farms, the economic evaluation in the context of net present cost (NPC), levelized cost of energy (LCOE) and investigation of the environmental impact. Grid-connected and standalone solar PV systems were developed for comparative studies. The estimated daily energy consumption for vertical farms in Selangor and Kuching was 430.116 kW h and 1002.024 kW h. Energy generated by grid-connected solar PV systems supported 11.6% and 8.35% of the load consumption in Selangor and Sarawak. The performance ratios of grid-connected solar PV systems in both selected sites were 82.22% and 82.56%. The finding proved that proposed work has significantly reduced the dependency of the utility grid. Additionally, the LCOE with solar PV integration vertical farming system appeared to be lower than the LCOE of the grid and lower CO2 emission. This paper serves as a reference guide to the vertical farming stakeholders, national policy-decision makers and non-profit organizations who planned for similar initiatives especially those within the tropical climate regions.