Advancing electricity access and enhancing livelihoods for islands
and remote communities
Renewable mini-grids, which combine loads and renewable energy resources, are seeing growing motivation for their deployment, driven by the many benefits these integrated energy infrastructures can bring to key market segments such as islands and remote communities. Renewable mini-grids can provide electricity access, increase power resilience and reliability, reduce energy costs and carbon footprints, and improve the quality of life. With increasing deployment, it is crucial to look at these systems’ performance, durability and adaptability to new developments. This sheds light on the crucial role of developing quality assurance mechanisms and so called“quality infrastructure”, explained in depth in this report, to successfully secure robust renewable mini-grids that can serve present and future human generations.
Today’s renewable mini-grids
Many efforts have been made to collect mini-grid data, but multiple sources still vary from one to the other. As a very fast-moving sector in recent years, it hasn’t been easy to estimate the global share of mini-grids, grid-connected and off-grid, powered by renewable energy sources. Estimates are clearer for the global share of mini-grids: there are about 19 000 installed mini-grids globally, and about half use diesel and other fossil fuel-powered generators (ESMAP, 2019). There is a great market potential to replace this large quantity of emitting mini-grids with renewable energy sources.
As illustrated in Figure 2, IRENA analysis identified an installed capacity of 4.16 gigawatts (GW) of offgrid renewable energy mini-grids, serving a population of at least 8 million people. Bioenergy-based mini-grids show the highest installed capacity, due to the fact that they are often used in high-power industrial mini-grids. Wind- and hydropower-based mini-grids are deployed across different end-use sectors. Hydropower mini-grids in particular have recently increased their deployment in the residential and industry sectors. Solar photovoltaic (PV) mini-grid installations are commonly used for commercial, residential and agriculture purposes.
When possible, interconnecting a mini-grid with another one or with the main grid can bring a series of benefits, changing the operation mode of mini-grids. The different mini-grid types are summarised in Figure 3. Grid-connected renewable mini-grids can make the power supply more reliable and resilient as well as boost renewable sources to be a significant contributor to energy generation. However, autonomous renewable mini-grids are mainly relevant for remote areas, both for rural electrification and
for facilities in remote areas. The off-grid and interconnected mini-grids are expected to see enhanced deployment in coming years, and the grid-connected segment is expected to see the biggest growth as a result of the increasing mini-grid activity of utilities and growing grid issues in urban, commercial and industrial areas.
Examples of mini-grid cost breakdown
Mini-grid 1 is an island mini-grid in the Pacific. The existing conventional diesel generators are progressively being phased out and some existing conventional diesel generators retrofitted for biodiesel (1.2 million litres per year) to obtain a 90% share of renewables. The LCOE of the system was calculated to be USD 0.39 per kilowatt-hour (kWh). A sample cost breakdown of recently deployed mini-grids is given in Table 2.
Mini-grid 2 is a small hybrid PV-diesel mini-grid in Southeast Asia. The LCOE of the system was calculated to be USD 0.39/kWh as well.
Although the cost of mini-grid hardware has generally declined in recent years as a result of increased competition and policy-driven incentives, the downwards evolution of “soft” costs, which are associated with customised engineering studies and regulatory, environmental and interconnection compliance, is sometimes restricted because of non-competitive regulatory friction (Cherian, 2017). As a result, these costs currently represent a larger percentage of total costs compared with past years.
Mini-grid situated in power sector
The Infrastructure Development Company Limited (IDCOL) is a state-owned financial institution. It integrates inputs from various stakeholders (government, private sector, non-governmental organisations, multilateral and bilateral institutions, academics) and is managed by government and private-sector representatives. Most of the international standards that are currently mentioned in the Supplier Enlistment Process under IDCOL Solar Mini-Grid and Rooftop Projects (IDCOL, 2017) are related to photovoltaic (PV) modules (e.g. IEC 61215:2005, IEC 61646, IEC 61730). IDCOL allows only low-maintenance lead-acid type batteries in its projects, most likely because operational safety standards of Li-ion batteries are too costly and complex to comply with. Bangladesh has recently surpassed what is defined as the market assessment stage, so current IDCOL QI strategies will be presented in the next section as well.