INTERNATIONAL RENEWABLE ENERGY AGENCY Renewables-based mini-grids: status and challenges 6 th World Summit for Small Wind Husum, Germany, 19 March 2015
IRENA s membership Membership: 172 affiliates - 140 members
Opportunities for mini-grids in developed countries 3
Expanding electricity access The rural electrification rate globally rose from 61% to 70% in 20 years Rural Sub-Saharan Africa 18% Rural Developing Asia 75% Source: Global Tracking Framework, 2013 Crucial role of off-grid solutions (stand-alone and mini-grids) to achieve universal electricity access
Opportunities for renewables in off-grid systems Some 1.16 billion people without electricity access today 26 million households served through off-grid systems 50 250 GW potential to hybridise existing diesel generator capacity, 12 GW on islands 1 million telecom towers in South Asia and Sub- Saharan Africa Source: World Bank 5
RE competitiveness
Renewable mini-grid and off-grid systems: Status 2012/13 Source: IRENA 2015
The challenges Limited available data for planning Old inflexible or incompatable diesel generators Limited options for balancing Source: Green growth Simple network structures Source: Green growth Limited training oportunities Offgrid system safety and standards Financing Source: Green growth 8
Minigrid categorisation Size (kw) Capability Complexity Stand-alone systems 0 0.1 Pico-grid 0 1 - Single controller Nano-grid 0 5 - Single voltage - Single price - Controllers negotiate with other across gateways to buy or sell power Micro-grid 5 100 - Manage local energy supply and demand - Provide variety of voltages - Provide variety of quality and reliability options - Optimise multiple-output energy systems Mini-grid 0 100 000 - Local generation satisfying local demand - Transmission limited to 11 kv - Both grid-tied and remote systems - Preference for DC systems -Typically serving single building or single load -Single administrator - Incorporate generation - Varying pricing possible - Interconnected customers 9
Proposed categorisation Stand-alone Grids DC AC AC/DC AC System Solar lighting kits DC Solar home systems AC Solar home systems; singlefacility AC systems Nano-grid Pico-grid Micro-grid, Minigrid Full-grid Application Lighting Lighting and appliances Off-grid Lighting and appliances Lighting, appliances, emergency power all uses all uses User Residential;Com munity Residential;Com munity Community; Commercial Community;Com mercial Community;Com mercial;industry Key component Generation, storage, lighting, cell charger Generation, storage, DC special appliances Generation, storage, lighting, regular AC appliances. Building wiring incl. but no distribution system Generation + single-phase distribution Generation + three-phase distribution + controller Generation + three-phase distribution + transmission
Voltage Integration of variable renewables on islands: The technical challenges Disconnection of generation 60 / 50 Hz The frequency of a system depends on the instantaneous balance of power Grid voltages and frequency must be mantained within defined limits allowing the consuption of electricity from customers The system must be able to handle continually changing demands for active and reactive power Disconnection of load The system must be able to survive to feasible disturbances of different nature Vmax Voltage control node Loads Systems were designed to operate with conventional generation Island networks are not interconected and are more sensible to changes in voltage and frequency Vmin Voltage control is achieved by production and consumption of reactive power Diesel generators have traditionally taken over the function of frequency and voltage control in islands 11
The technical solutions Smart grid technologies Energy storage solutions Demand side options Advanced control systems Distribution automation Smart / grid friendly inverters Smart advanced metering Data collection technologies Forecasting Batteries Flow Batteries Flywheels Thermal storage Pumped hydro Demand response Electric vehicles Desalination
Available international standards for PV systems The IEC has developed standards for critical components of off-grid PV systems: solar module, charge controller, lead-acid battery, inverters Panels: IEC 61215 Ed. 2.0: Crystalline silicon modules IEC 61646 Ed. 1.0: Thin-film photovoltaic Charge Controllers: Charge Controllers: IEC 62509 Ed.1: Performance and functioning of photovoltaic battery charge controllers IEC 62109: Safety of power converters. Part 3: Controllers Inverters: IEC 62109 Safety of power converters for use in photovoltaic power systems. Part 2: Particular requirements for inverters. BOS components and minor equipment: IEC 60669-1: Switches for household and similar fixed-electrical installations. Part 1: General requirements. IEC 60227-1-4: Polyvinyl chloride insulated cables of rated voltage up to and including 450 V/750 V-Parts 1-4: General requirements Source: Alliance for Rural Electrification (2011) Technologies, quality standards and business models
IRENA (In Press) Quality Infrastructure for Small Scale RET International Standards for Small Wind Turbines IEC Standard Standard Title Status IEC 61400-2 Wind turbine Part 2: Small wind turbines 3rd Revision 2013 for turbines less than 200 m 2 2 nd Revision 2006 1 st Revision 1995 IEC 61400-11 Wind turbine generator systems Part 11: Acoustics noise measurement techniques 2006 IEC 61400-12-1 Wind turbines Part 12-1: Power performance measurements of electricity producing wind turbines 2006 IEC 61400-14 Wind turbines Part 14: Declaration of apparent sound power level and tonality values 2005 IEC 61400-22 Wind turbines Part 22: Conformity testing and certification 2010
QI should develop hand-in-hand with local market stages Increased SWT Quality Assurance 5. Mature Market 4. Market Consolidation Accreditation: Needed for test labs, certification bodies, training, inspection QI & Market Development: Standards and QI maintenance, reduce QI development budget and end user incentives comparable to other energy technologies International QI: Link with international groups with consumer information including certificates and labels IEC RE Test Laboratories: Unaccredited moving to accredited, independent 3rd party test results to IEC standards Consumer Information: SWT Consumer Labels with end user education Standards: Continuous development moving towards international standards Certification bodies: Establish certification bodies 3. Market Growth Testing: Low-cost SWT testing (duration & performance) Training: Refine training/courses, develop credential/tests/training guides for practitioners Standards: Complete standards for market access (include grid code, planning, permitting, etc) QI and Market Development: Begin end user incentives 2. Market Introduction Training: Establish courses for SWT practitioners and import inspectors Demonstration projects: Build consumer awareness and offer hands-on training Import regulations: Meet specific standards or certification from country of origin Standards: Develop national/regional standards based on IEC standard 61400-2 1. Market Assessment Studies: Inventory existing in-country QI, wind resource and expertise Analyses: cost/benefit for SWTs and cost of SWT QI stage options Planning: national and/or regional QI and policy options by market stage IRENA (In Press) Quality Infrastructure for Small Scale RET
Policy support needed for technology development Technology awareness and transfer Smart grid technologies Electricity storage Information and data on progress Categorisation of off-grid renewable energy systems Performance and costs data Regulation, standards and grid codes Analysis and tools Grid stability studies Cost-benefit analysis Project development Training Design Operation & maintenance
Mini grids Innovation 17
Renewables-based mini-grids will play an important role in a future sustainable energy regime Francisco Boshell fboshell@irena.org
Some Technology Strategies to Deal with Power Variability Additional Generation: Application: rare short-term peak Technology solutions: Secondary/emergency diesel generators. Dispatchable Generation: Application: frequent short, high peak Technology solutions: Advanced controlled (inverters) diesel generators. Energy Storage: Application: daily cyclical balance of load and generation Technology solutions: Decentralized batteries, flywheels. Dispatchable Load: Application: compensate frequent short, high production peaks Technology solution: Air conditioning. Additional Load: Application: compensate rare production peaks Technology solutions: District and local heating/cooling. 19 Sources: Adapted from: Fraunhofer UMSICHT, Hybrid urban energy storage, (May 2012)