Ac Mini-Grid Workshop: 2017 IEEE Power Africa Conference Powered by: IEEE Smart Village Initiative In collaboration with: GVE Projects Ltd. Nigeria www.gve-group.com Torch Bearers Foundation, Cameroon www.thetorchbearer.org 1
Definition of a Mini-Grid Small to medium sized power sources supplying electricity to domestic, productive and public users via a local distribution network (mostly to a remotely located community) Not connected to any national electricity grid and therefore operated as isolated mini-grids in island mode In some cases, interconnected mini-grids can be operated with a (part time) connection to a larger transmission / distribution grid Different energy resources and power plants (diesel, hydro, biomass, solar, wind, hybrid), mostly AC coupled low voltage system with a centralized production and a storage system Renewable energy sources have become the most economical viable power source for mini-grids in most places, increasingly replacing diesel gensets or reducing diesel fuel consumption 2
The Process Flow 3
FEASIBILITY STUDY
GUIDING FACTORS FOR GROUND WORK Reliability, durability and efficiency Less costly (cheaper than whatever source the community is using) Acceptance (very critical ) Sustainable
MOST IMPORTANT FACTORS A. Village selection criteria B. Village awareness creation campaigns C. Energy resource assessment D. Demand assessment in village selected E. Community ownership (Exclusivity contract with village)
Village selection criteria (AC micro grid ) The distance from national grid Plans of national grid extension to that community by the authorities The topography of the area Demographic description of the areas Settlement pattern (linear or cluster ) Technical data (sun hours)
EXAMPLES OF SETTLEMENT PATTERN (LINEAR OR CLUSTER ) Linear settlement Clustered Homes
Village awareness creation campaigns (Mind set change) Meeting with village authorities(chiefs and quarters head etc) business men in the community Door to door visitation of villagers
ENERGY RESOURCE ASSESSMEN Identification of available resources (what are the villagers currently using to meet thier enrgy needs? "lighting and power". Measuring of available resources (what quantity of fuel or kereson is used and for how long?
Demand assessment in villages selected Cost of available energy sources( how much does each villager spend on energy?) Means and cost of getting the energy sources Economic activities of the place(how busy is their market?) How many energy related businesses are currently running? How many schools, hospitals and local government offices are available in the community What type of electrical equipment are available in that community Tariff setting (will your tariff per KWH cheaper than what there are currently spending?
EXAMPLE OF ECONOMIC VIBRANCE Village Market Village shop
Cumunity ownership(exclusivity contract with village ) Intergrate village men who were involved in providing other sources of energy to the cummunity(petrol and kerosene sellers) Training for Village management Committee,a group of workers (technitian,book keeper and village vigilante group
Thanks
PV Solar Mini-Grid Layout 1. PV array 2. Solar inverter 3. Battery inverters 4. Battery Banks 5. Back-up Gen-set 15
Mini-Grid User Categories 16
Mini-Grid vs Other Technologies Solar Home Systems / Lanterns Micro-grids Micro-Grid Operator Expansion by Utilities Full Energy Ladder? Cost Limited to light, phone charging and radio? >$5.00/kWh energy prices Scalable to grid equivalent power Affordable energy prices and low capital costs Full electrification High capital costs Timeline Short installation time Quickly deployable Multi-year project timelines Reliability 1 7 Limited product life Stable and durable Intermittent power cuts
Power Generation System Design The mini-grid system can be a DC or an AC coupled power system. Simulations with the mini-grid design software HOMER show that with the size selected and the long term perspective of the investors taken, a solar power system with battery storage combined to a diesel generator produces the lowest electricity generation cost. 18
Distribution Network Design Source: GVE Angwan Rina Mini-Grid Site, Plateau State Nigeria 19
Revenue Collection: Specially Designed for Mini-Grids in Rural Areas Highly Secure with Tamper Proofing technology & Weather Protection (IP54) Supports 2-Way Communication for Remote Monitoring & Control Multiple Vending Options 1-Way Meter Box 4-Way Meter Box 20
Mini-Grid Operator Models PUBLIC MODELS Fully subsidized and publicly managed mini-grids have proven widely unsuccessful COMMUNITY MODELS Cooperative approaches have proven to work if the cooperative is structured like a private sector company including ownership models PRIVATE MODELS If the profit of the private company is linked to the operational success of the mini-grid, the power supply becomes sustainable 21
Load control system Load limiters? Circuit breakers Fuses and Fuse links
Maintenance Repairs and changing of fuses, fuse links and breakers Repairs of charge controller and inverters Repairs on low voltage distribution line Fault finding
Licensing and validation Concession rights- $182,000 License - $45,000 Authorization $45 MoUs Huawei Solar Plant in Cameroon
Economic operations The balance between energy cost and sustainability Energy use prioritizing
Customer relations The need for prompt communication Database for all customers attitude tracking
Bills recovery Monthly billing systems Daily billing systems
Customer bad practices Energy theft Anarchical electric works Recalcitrance towards payment of bills Manipulation of fuse links
Customer tracking Data collection System monitoring with the DAS Data relating to solar array type and temperature effect on energy production Energy Consumption trends Impacts Data Acquisition System for technical data collection within the power house
Necessity for In-country Partnerships Municipal authorities The political elite Local Chiefs and village elders Ministry of Energy
Thank you for your participation info@gve-group.com www.gve-group.com Twitter: @GreenVillageEle... Creating a Reliable Renewable Energy Future!!! 31