Potential of Micro Gas Turbines to Provide Renewable Heat and Power in Off-Grid Applications for Desalination and Industrial Wastewater Treatment

Abstract

The demand for all types of resources (food, freshwater, energy and raw materials) has increased alarmingly due to the continuous techno-economic development of society, bringing about a pressing shortage not only in low-income countries but also in more developed economies. Such is the case for the very wealthy countries in the Gulf Cooperation Council, which are currently struggling with the lack of fresh water supply, or certain countries in Latin America where the contamination of natural water sources poses a major environmental threat. In order to assess this water-energy nexus problem, this paper looks into systems where the production of renewable power is combined with either freshwater production (through desalination) or industrial wastewater treatment for effluent control. Three enabling renewable energy technologies are assessed: solar micro gas turbines, wind turbines and photovoltaic panels. In all cases, off-grid installations are considered. The paper describes the characteristics of these three systems and provides a comparison of technical specifications, yield and costs. Wind and photovoltaic are the standard approach, as already proven by a number of commercial plants, but solar micro gas turbines exhibit additional flexibility (in particular when hybridisation is considered) and have the differential feature of producing not only electric power but also heat. This enables the combination of different types of water treatment technologies in order to increase water production/recovery which, in turn, reduces the environmental impact of the production process associated (either freshwater or other good or service).

Innovative desalination system driven by a solar micro gas turbine for off-grid applications

“…Further to the aforecited potential of micro gas turbines for decentralised power, in particular applied to renewable energy sources, and based on the past experience of the authors, a solar desalination system based on SmGTs with the techno-economic features already presented in [13][14][15] seems to be a cost-effective solution with a promising future against other popular renewable desalination options integrating PV panels. This has already been explored for isolated units [16] but, according to recent literature on the topic, it might also apply to larger scales by coupling several SmGTs in parallel.…”

“…Given the inlet conditions and mass flow rates at both sides of the recuperator, the outlet conditions can be calculated with Eqs. (13)(14)(15), where the rules to scale the rated value of conductance and to compensate for the variations of thermodynamic 13 properties throughout the recuperator have been validated experimentally by the authors in [49], for fluids with both ideal and non-ideal gas behaviour.…”

Market Opportunities of Water Treatments Powered by Solar Micro Gas Turbines: Chile and Ecuador Case Studies

“…The assessment performed intends to evaluate the overall economic viability of solar PV and wind technologies by comparing their Levelised Cost of Energy (LCOE) and Levelised Cost of Water (LCOW) with IRENA's (International Renewable Energy Agency, Abu Dhabi, The United Arab Emirates) approach [45], estimating costs from the perspective of private investors and basing the selection of the locations on mining industry density. Other assessments addressing the power capacity production and some costs considerations of these three systems were carried out previously [46].…”