Assessment of electricity demand-supply in health facilities in resource-constrained settings: optimization and evaluation of energy systems for a case in Rwanda

摘要

In health facilities in resource-constrained settings, a lack of access to sustainable and reliable electricity can result on a sub-optimal delivery of healthcare services, as they do not have lighting for medical procedures and power to run essential equipment and devices to treat their patients. Currently, diesel generators are the most common solution to this issue; however they are expensive due to high fuel prices and required on-going maintenance. Also, connection to the grid in rural areas is often unreliable with frequent power outages. Renewable energies however, are cleaner solutions, but they are intermittent and capital intensive. Therefore, what would be the optimal combination to satisfy the demand of a rural health facility? Few studies have provided with empirical evidence of the linkages between electricity and the delivery of healthcare services. Health facilities require electricity for lighting, support child delivery, perform surgical procedures, emergency night-time care, refrigeration for blood and medicines, and to run other essential medical equipment. Therefore, the present research project intends to develop a protocol with the following purposes: (1) to study how to optimize energy systems in resource-constrained health facilities with renewable energies, and (2) to explore available data for assessing the impact of electricity supply on improving the delivery of healthcare services. A health facility in Rwanda called Gikomero is deeply studied as an example, focusing on solutions to improve their current electricity system, which is unreliable. In this study, the health facility is regarded as a system that requires reliable electricity supply to deliver healthcare services adequately. The main goal of optimizing the health facility's energy system is to improve the delivery of healthcare services. For a system analysis, internal and external requirements must be met involving reliability and sufficiency, and cost and sustainability. To assess electricity supply in health facilities, the local context must be studied individually and in detail. Data is collected on size of health facility, healthcare services delivered, electricity needs for equipment, current and future electricity demand-supply profiles and patterns over time, indicators of healthcare performance and diverse energy supply options that are suitable for a resource-constrained health facility. The HOMER simulation software is being used to optimize the different energy options in terms of economic, technical and environmental aspects to satisfy its current and future demand while showing various scenarios. Furthermore, to assess the impact of electricity in healthcare services delivery; data is collected on health-related indicators and electricity consumption to analyze change over time and visual relationships between these indicators. The current demand of Gikomero health facility (HF) is dominated by the consumption of medical equipment, consuming 37% of the total electricity demand. Electricity supply options to satisfy the current and future demand of Gikomero HF are grid-connection, stand-alone diesel generators, solar PV panels, micro-wind turbines, micro-hydro power and biomass. The last two options were not feasible for this particular context. Energy storage systems such as batteries are expected to play an important role on increasing reliability, as systems relying only on renewable energy sources are vulnerable on their supply. Results show that a Business-as-usual (BAU) scenario has very high Net Present Costs (NPC) in comparison to other optimal scenarios that add new energy solutions. The BAU scenario however, shows the total costs of meeting the demand with sufficiency, meaning that blackouts are avoided through a generator running on a minimum load at all time (a perfect-functioning health facility). Also, the 'only renewables' scenario is very expensive, mainly due to capital-intensive technologies. The simulation results show that the most optimal option for the current system implies the addition of a 2kW solar system and 5 batteries, however when taking into account the future demand, the option proposed by Great Lakes Energy (GLE) of a 3kW solar system would be the most optimal, although with 5 batteries instead of 10 to avoid large expenses and oversizing. Moreover, results also show that storage is a really important aspect in resource-constrained health facilities. A 'no storage scenario' is very high on costs in the long-term, becoming un-affordable for the health facility. Here, batteries are considered as the 'game changers' and critical points for the reliability of the system. Furthermore, it was determined that the BAU system is oversized with a 12,5kW diesel generator, and that there are current energy losses in the system; this confirms the need for a storage system, even if renewable energies are not included. However, storage represents an argument for installing renewables to increase cost-effectiveness and independency. In terms of environmental emissions, the BAU scenario contrast highly with other scenarios so there is a need for an immediate response through an increase on the renewable fraction of the system.