1.1 What is a mini Grid?
A mini-grid is a network of small-scale electricity generators and possibly energy storage systems connected to a distribution network that offers power to a small, localised set of customers while staying independent of the national transmission grid. They can range in size from a few kilowatts to ten megawatts. Smaller mini-grids are referred to as micro-grids or nano-grids. Customers can be served in a variety of ways using mini-grids. Examples include private households, commercial businesses such as shops, ice machines, and mobile phone chargers, agricultural loads such as irrigation pumping and cold storage, productive loads such as grind mills and wood or metalworking shops, and semi-industrials such as telecom towers, processing plants, or farms.
Mini-grids can be built and operated by state utilities, commercial enterprises, communities, non-governmental organisations, or a combination of multiple stakeholders, such as public-private partnerships. Different public and private players may construct and operate generation and distribution assets. Mini-grids can be powered by diesel, renewable energy (solar PV, hydro, wind, biomass, and so on), or a combination of the two. A large portion of the power generated by green mini-grids comes from renewable sources.
To begin operating a mini-grid firm, the developer must examine the project’s feasibility, choose a corporate structure, and hire local employees.
1.2 Assess Feasibility
Feasibility analysis of the mini-grid possibility, which will determine the profitability of proposed projects in the local market, must first be carried out. The feasibility study typically covers the Proposed project sites, projected demand (usually based on extrapolation of socio-economic data from the most recent national census, which must be confirmed through a detailed demand assessment for the final technical design; existing and potential rural electrification; local legal, policy, and regulatory, framework, permitting and compliance requirements. Locating and hiring the service of a developer who is conversant about detailing feasibility is very essential. With a vast knowledge and experience of the Energy Project Africa (EPA) team, we conduct a feasibility study that will save your resources and at the same time save you from stress. At EPA, we carried out a feasibility study that evaluates your mini-grid project’s potential for success; as we take perceived objectivity as essential. We take you through the four essential processes of the feasibility study, economic, legal, operational and scheduling. We estimate and give you how much time the project will take to complete. We observe and identify any constraints the proposed project may face and solve them prior to project commencement.
Defining the geographic scope of the project after a successful feasibility study is the next step for the prospective mini-grid owner.
Define the Geographic Scope of the Project
The next step in mini-grid design is to figure out the project’s geographical scope as well as the total number of consumers it will serve. A mini-grid can power multiple towns, a single hamlet, or a collection of structures. When selecting a resource and power generation technology, the number and kind of consumers (communities and businesses) are crucial factors to consider. Geographical considerations such as terrain and the ease with which resources may be acquired will influence system design. Finally, rules and plans that may affect the mini-grid in the future must be considered. EPA is well equipped with trained personnel to help you locate and define a geographical area.
Collection of Data
Secondary data is typically used to find the most potential sites in the first round. Data from national rural electrification programmes, Geographical information service (GIS) data on un-electrified villages and renewable resources, and feedback from government officials and national distribution grid corporations might all be utilised. However, prospective mini-grid owners should be aware that this information may not be up to date or reflect current conditions. Don’t worry!! We got your back. With our team of researchers and data analysts, Energy Project Africa is ever ready to collect and analyze up to date data for you to be able to own an efficient and reliable mini-grid. Energy Project Africa performs a site visit in the third step to double-check the preliminary data, establish contact with the relevant community and public bodies, and analyse the community’s appetite for the mini-grid.
Conducting a detailed renewable resource assessment
At this point, a comprehensive renewable resource evaluation for solar-based mini-grids is required. This is usually not necessary because irradiation data from GIS is easily available and usually accurate enough for device technical design. If no past renewable resource data exists, Energy Project Africa will perform a study to gather the seasonal data required to actualize your mini-grid dream. Energy Project Africa, which has a team of skilled data analysts, conducts complete research of existing and prospective mini-grid demand in the region. This is necessary because if demand falls short of expectations, the mini-revenue grids may not be enough to cover the project’s fixed costs, let alone pay for maintenance or replacement equipment. Demand forecasting is especially important for mini-grid systems that are difficult to scale up or down to meet demand (such as hydro projects or non-hybridized plants without the benefit of cheap diesel engines). For these non-modular systems, demand-side management is critical to guarantee that electricity demand does not exceed supply, which could lead to community strife.
1.3 Assess Available Energy Resources
After determining the project’s geographic scope, it is necessary to assess local energy resources, including quantity, availability, cost, sustainability, and potential competing applications. Mini-grids necessitate stable, cost-effective energy sources capable of meeting local power demands, and each resource has its own set of benefits and drawbacks. For example, a mini-grid in a region with seasonal biomass supplies may provide on-demand power for a mill but not year-round electricity for a town. In drought-prone areas, hydropower may not be a reliable year-round resource. During the assessment process, it is necessary to work closely with local populations. Natural resource users in their communities can give important information about availability and potential conflicts. EPA chooses the energy-producing technology after determining the most promising resources (or technologies). For each energy resource, EPA can choose from a variety of technologies.
1.4 Size the System
The size of a mini-grid determines its maximum power output. The power-producing system’s installed capacity should be sufficient to meet load requirements. To size the system, planners must calculate load fluctuations in half-hour intervals and anticipate future load growth. Estimating and planning for current and future loads is essential, particularly in terms of financial viability. EPA can estimate current loads based on our extensive energy audit experience and knowledge. Moreover, with the present data, we forecast future loads based on demographic and economic expansion which is more difficult for our competitors to analyze. EPA makes use of Hybrid Optimization of Multiple Energy Resources software to model and specifies a system’s predicted loads, network architecture, consumption, and cost.
1.5 Select the System Configuration
Mini-grids are divided into three categories: alternating current (AC) coupled, direct current (DC) coupled, and hybrid (both AC and DC). Energy-generating methods, system sizing, and battery consumption are the most important factors to consider when deciding which configuration to use. Different energy-producing technologies favour different designs. AC is produced by hydropower, geothermal energy, diesel power, and biomass-based power, hence AC configurations are prevalent. Solar PV systems produce DC, whereas wind turbines can produce AC or DC. As a result, system designers must select between different configurations. The cost expected usage, and plans to eventually integrate into a larger (typically AC) network are all important factors to consider.
Any arrangement involves compromises in terms of costs, maintenance requirements, efficiency, safety, and end-use adaptability. AC systems, for example, make it easier to transport electricity over long distances, but they are also more complex and costly. Despite the fact that DC systems require less equipment to condition and transform power, DC technology is only deployed in a few consumer devices. Additionally, switching from AC to DC results in energy losses (and therefore in money). Shorter lengths, lower voltages, and systems generating less power are common uses for DC setups (W rather than kW). Longer distances, greater distribution voltages, and systems generating more power are more often utilised AC arrangements, which transmit power more effectively (MW). Small grids of a few kilowatts, on the other hand, can use AC.
In addition to a current type, you must choose between a single-phase or three-phase system. Single-phase systems can’t handle as many load types as three-phase systems can. Single-phase systems are frequently used to power lighting and resistive loads. Three-phase systems can handle a larger range of loads, including large motors, than single-phase systems. To connect to the national grid, mini-grid systems frequently require three-phase systems. In terms of inverters and wiring, single-phase systems are less expensive, but they do necessitate more expensive transmission cables. Three-phase inverters and switches, on the other hand, are more expensive.
1.6 Design the Distribution System
The system layout and pick system attributes must first be created before designing the distribution system. The next step is to model system performance using the preliminary layout and system attributes. Once the distribution system’s model has been built, developers can evaluate different conductor sizes based on the load distributed over the system. Project developers can test differences inline routing, single-phase versus three-phase service, and loads after finishing the basic case model. Design crews identify the distribution system’s structural (rather than electrical) design aspects after planners have established system layout and quality. The design team compiles a materials list based on benchmarks for the type and number of pole-top structures required for the line length and then calculates the distribution line’s overall length. Crews complete a final survey of distribution system alignments to establish pole placements, buildings, and other requirements.
Mini-grid distribution systems are often more advanced than traditional grid distribution systems. Unlike typical grids, mini-grids can support bidirectional power flows as well as a variety of energy sources. Additional controls and software are required at this degree of operational complexity.
When designing a distribution system, keep in mind the end-user system, which includes metres. Tariff collection and the commercial aspects of the mini-grid project are the most important factors to consider when selecting metering systems. Developers may choose the payment option throughout one of the various stages of the design process. Depending on the required restrictions, some developers may construct metering and payment systems before the technical systems. The end-user system should handle loads and prices while taking into account the local cultural environment and user preferences.
1.7 Policy and regulatory issues
Policy and regulatory issues often hamper the growth of mini-grids, especially issues around tariffs, licensing and the arrival of the national grid. There are existing laws and regulations that are dedicated to private investment in mini-grids and in Africa.
The majority of countries in Sub-Saharan Africa have identical national tariffs, which means that whether residential consumers are connected to the national grid or live in remote rural areas served by a mini-grid operator, they pay the same rate. State-owned mini-grids are cross-subsidized because mini-grid electricity is often more expensive than grid electricity.
Private mini-grids must make a return on their investment in order to be profitable, which implies cost-reflective pricing or government subsidies. Many governments do not allow cost-reflective rates, impeding the development of private mini-grids. With the exception of very small mini-grids, tariffs will almost definitely need to be approved by the local regulator.
Licences and permits
Another issue is obtaining licences and permits. Licensing may be required for electricity generation, distribution, and supply. In several nations, there are no clear rules for mini-grid licences. Obtaining a licence can be a lengthy, bureaucratic, and unclear procedure involving multiple government agencies in some circumstances. Most countries currently require a unique set of rights for each mini-grid, which might take a long time for developers. A wide range of documents may be required to get a licence approved, including:
- Certificates of incorporation;
- Land lease or ownership documents;
- Construction permits;
- Environmental and social impact assessments (ESIAs);
- Health and safety certificates;
- Water use rights (for hydro projects); and
- Rights of way
For larger projects, it may also be necessary to have a concession contract or a power purchase agreement (PPA). EPA maintained a good and cordial relationship with the regulatory agencies in charge of the document. This is another reason why you should give us a chance to go through the process for you
1.8 Technical design of mini-grid systems
The technical design of mini-grid systems is relatively straightforward compared to other steps in the mini-grid development process. There is technical software that enables the creation of systems to meet present and future needs. The key is to ensure that the design is carried out by experts with the requisite skills and experience in planning, installation, commissioning, operation, and maintenance of the technology in question. Power generating and distribution systems can deliver AC or DC electricity. In nano-grids that produce DC power, small PV-battery systems without inverters are typically employed, which reduces costs but limits the area of coverage for each nano-grid? In renewable AC power mini-grids, hydro, biomass, PV/PV-hybrid, and wind systems can all be used to generate electricity. Both AC and DC systems require suitable monitoring and control systems to collect data and manage the grid. The guiding principles for technical design are that the mini-grids should be safe; adequate; up-scalable and efficient.
Safety: To ensure that the systems are as safe as possible, they should be built in accordance with the respective country’s electrical codes and standards. There are also standards for frequency and voltage levels.
Adequate: According to the business model, the systems are regarded as ‘sufficient’ provided they offer the pre-defined quality of service and quantity of electricity to clients
Scalable: The systems are up-scalable if they can meet demand increases at a lower life-cycle cost, and they are efficient if they provide electricity at the lowest possible cost.
Efficient: The scale of power-producing systems is determined by demand. Sizing must also take into account constraints such as renewable resources, finance, and environmental regulations. Limits on the use of water, biomass, or diesel, as well as noise and emission restrictions, are frequently outlined in the environmental social and impact assessment or resource usage rights.
The design team will need to go to the location to customise the distribution grid systems to the local needs. When designing a mini-grid system, customers, interior electrical installations, and metering must all be considered. Local rules and standards often apply to connections and indoor installations, and they must be incorporated into any design. It is important for mini-grid developers to take time to understand the needs and priorities of the communities in which their mini-grids are located and to make sure that the projects have broad local support.
1.9 The procurement, installation and commissioning of the mini-grid
The procurement, installation and commissioning of the mini-grid require a lot of planning, good logistics, and technical supervision.
The process of locating, obtaining, and purchasing goods and services from a third party, usually through a tendering or competitive bidding system, is known as procurement. Before building and activating the system, developers may issue tenders for individual mini-grid components. They could alternatively submit a bid for a turnkey solution, in which the contractor provides a fully operational project. In most cases, the latter is more expensive. Government-funded and international donor-funded projects must generally adhere to transparent procurement requirements, such as the EU’s PRAG rules.
The Energy Project Africa is often involved directly in procuring components and delivering either lead-acid or lithium batteries for African communities and businesses’ uses. This is accomplished with the affiliation of battery manufacturers for African use. The procurement is actualised with work by European and American manufacturers, including Pylontech, which focuses on developing new lithium battery solutions, Schneider, Fullriver; Index-Exide; and Deka. Many African communities and businesses are hampered by insecure and unsustainable grid supplies, as well as excessive electricity prices. We are proud to be a Nigerian firm, and we aspire to construct a future in which the local energy storage sector becomes more cost-effective, innovative, and competitive; we also hope to develop products that help both the communities and businesses in Africa.
Mini-grids should only be installed under the guidance of qualified and experienced experts. It is critical that the developer has established legal rights to the mini-grid site before beginning installation. It’s also critical that they do quality checks on delivered equipment and locally made products (such as foundations, channels, and bricks) before starting work, and that all personnel, including local support staff, receive safety training.
For equipment installation, specialised installation tools and local language instruction manuals must be provided and used appropriately. For reporting purposes, installation protocols and photographs should be taken. A list of assets installed and where they were installed is required by many contributors. All packaging and other waste materials must be disposed of in an environmentally friendly manner and must meet the environmental impact assessment’s requirements.
The final stage of the project is commissioning, which entails ensuring that all mini-grid systems and components are planned, installed, tested, operated, and maintained in compliance with the developer’s operational requirements. Technical testing on the mini-grid (e.g. voltage, frequency, and emergency stop) must be done either by an independent party or by collaboration between the installation and the client (i.e. the mini-grid creator). The commissioning protocol must be signed by all parties involved in the commissioning procedure.
Mini-grid operation and maintenance (O&M) is critical to their long-term viability and should be planned in advance. If O&M isn’t done properly, even the best-designed mini-grids can fail. The mini-grid utility can manage operations and maintenance in-house or contract it to a local company. Whatever model is chosen, the O&M team must have the required abilities, motivation, ethics, and community relationships. Local O&M actions should be meticulously documented in pre-defined reporting templates so that performance can be tracked by the mini-administration grids. The mini-management is frequently responsible for the following tasks: grids.
EPA provides 24/7 customer support via our network operations centre. We provide in-depth business insights in the form of value-added services to our corporate customers and industry-based clients as a company that takes responsibility for monitoring operations and managing solar rooftop upkeep. The necessity for regular and optimal solar system management has made it necessary for African communities and enterprises to rely on the EPA’s solar energy O&M expertise. We undertake highly standard O&M at EPA with our engineers, who have received thorough solar maintenance training and are well qualified to maintain solar systems and perform corrective measures as needed. EPA performs automatic as well as efficient system assessments to ensure that solar power plants are appraised in accordance with international standards, thanks to years of field training. When your solar isn’t performing as intended, our constant monitoring and inspections ensure prompt action. In general, our O&M teams handle all areas of solar power plant maintenance, ensuring that the plant runs well and that our clients receive uninterrupted power.
Energy Project Africa is a leading renewable energy business in Lagos, Nigeria with expertise in procurement of energy equipment, energy audit and feasibility solutions for mini-grid and solar farms. Supply by EPA provides solar products and equipment for corporate and institutional clients for the project and operational needs. If you need a partner with hands-on local expertise in the renewable energy space or any of our bespoke solutions/services, do contact us.