Optimisation of hybrid renewable energy systems in remote hospitals: Mexico's market conditions analysis
File(s)
Published version
Author(s)
Ochoa, Sofía
Acha, Salvador
Shah, Nilay
Type
Journal Article
Abstract
Hospitals in remote settings are major energy consumers that often rely on diesel generators to address unreliable power grids, underscoring the need for improved energy systems to ensure continuous patient care, reduce operational costs, and advance sustainability goals.
This paper presents an integrated optimisation model that optimises the selection, capacity, and operation of a hybrid renewable energy system (HRES) to serve power, heating and cooling loads of these critical facilities. Unlike existing HRES studies, this work is the first to present a policy-aware MILP optimisation of a remote grid-tied hospital in Mexico that explicitly models the case study location's grid unreliability, the full applicable Time-of-Use Medium Voltage Large Demand electricity tariff (GDMTH, Spanish acronym for Gran Demanda en Media Tensión Horaria) electricity tariff, and a detailed net-metering grid electricity export compensation scheme. The energy system design accounts for local regulations governing hospital backup systems and critical loads. In addition, it jointly evaluates interacting policy instruments and integrates electricity, heating and cooling within a diversified technology portfolio.
The MILP model used minimises the 15-year Net Present Value of total system costs. A case study of a remote hospital in Sonora, Mexico, demonstrates the benefits of an alternative to the diesel generator-based business-as-usual approach, considering technologies such as solar photovoltaics (PV), Combined Heat and Power (CHP), and battery systems. The results demonstrate that policy mechanisms are decisive for financial viability and for facilitating the deep decarbonisation of energy systems. The recommended configuration combines a mono-Si PV system with a CHP unit for electricity generation, along with an air-source heat pump and an electric chiller to meet thermal needs. This configuration yields attractive internal rates of return ranging from 17.1% to 20.4%, a 15-year NPV of savings of $285.6k to $404.3k, and a simple payback period of 5.1 to 5.7 years. The emissions were reduced by 51-85% with this configuration. These findings offer practical guidance for hospital decision-makers evaluating low-carbon energy investments and inform regulators on how policies shape the system's design and financial attractiveness.
This paper presents an integrated optimisation model that optimises the selection, capacity, and operation of a hybrid renewable energy system (HRES) to serve power, heating and cooling loads of these critical facilities. Unlike existing HRES studies, this work is the first to present a policy-aware MILP optimisation of a remote grid-tied hospital in Mexico that explicitly models the case study location's grid unreliability, the full applicable Time-of-Use Medium Voltage Large Demand electricity tariff (GDMTH, Spanish acronym for Gran Demanda en Media Tensión Horaria) electricity tariff, and a detailed net-metering grid electricity export compensation scheme. The energy system design accounts for local regulations governing hospital backup systems and critical loads. In addition, it jointly evaluates interacting policy instruments and integrates electricity, heating and cooling within a diversified technology portfolio.
The MILP model used minimises the 15-year Net Present Value of total system costs. A case study of a remote hospital in Sonora, Mexico, demonstrates the benefits of an alternative to the diesel generator-based business-as-usual approach, considering technologies such as solar photovoltaics (PV), Combined Heat and Power (CHP), and battery systems. The results demonstrate that policy mechanisms are decisive for financial viability and for facilitating the deep decarbonisation of energy systems. The recommended configuration combines a mono-Si PV system with a CHP unit for electricity generation, along with an air-source heat pump and an electric chiller to meet thermal needs. This configuration yields attractive internal rates of return ranging from 17.1% to 20.4%, a 15-year NPV of savings of $285.6k to $404.3k, and a simple payback period of 5.1 to 5.7 years. The emissions were reduced by 51-85% with this configuration. These findings offer practical guidance for hospital decision-makers evaluating low-carbon energy investments and inform regulators on how policies shape the system's design and financial attractiveness.
Date Issued
2026-12-01
Date Acceptance
2026-03-09
Citation
Energy Efficiency First, 2026, 3
ISSN
2950-1563
Publisher
Elsevier BV
Journal / Book Title
Energy Efficiency First
Volume
3
Copyright Statement
© 2026 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
License URL
Publication Status
Published
Article Number
100013
Date Publish Online
2026-03-11