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Renewable Energy and Mini Grids in East Africa
The Technical Challenges and Opportunities for
Developers, Investors and Off-Takers
5
Mini-Grids
— Mini Grid = Micro Grid
— Electricity distribution systems containing loads and distributed energy
resources, (such as distributed generators, storage devices, or controllable loads)
that can be operated in a controlled, coordinated way either while connected
to the main power network or while islanded. (CIGRE)
— Typically includes a mix of
dispatchable and non-dispatchable
power sources.
— Health & Safety of new electricity
users of utmost importance.
7
Global Market Trends
— Value of the market - $12 billion in 2016 and is estimated to reach $23
billion in 2021 (GlobalData)
— Mini Grids with renewables generation sources are becoming a go-to
option for project developers.
— US Mini Grid market:
— 39% of the global market share during 2016
— Forecasting 52% by 2021
8
Why Mini-Grids and Renewables in Sub-Saharan Africa?
— Rural energy access remains a
major challenge
— 1.5 billion people without access to
electricity
— 80% in rural areas
— Large proportion across the African
continent
— Centralised electricity generation
— Inequity in access is prevalent
even where supply has been
achieved
IEA, 2012
9
The Benefits of Mini-Grids
— Power connectivity to remote populations at lower cost
— Fast deployment
— Tailor design of Mini-Grid to local requirements
— Enhanced reliability of supply and resilience
— Integration of local / renewable generation sources
— Better environmental performance
— Trading / market access
—Grid-tied: market participation, aggregation of
resources, Mini Grid as a virtual power plant
— Islanded: community energy / markets
— Power quality
11
Energy Storage and Mini-Grids
— Energy storage acts as a balancing mechanism
— Whole range of benefits including:
— Energy management and reserves
— Avoids / defers reinforcement
— Improves power quality and reliability
— Improves system control
— Range of energy storage technologies:
— Batteries
— Pumped storage
— Hydrogen energy storage
— Thermal (molten salt)
— Compressed Air Energy Storage (CAES)
— High power flywheels
— High power supercapacitors
Photo courtesy of Anesco
Spector, 2016
12
Commercial Challenges
— Upfront capital investment. Main cost components:
— Generating plant
— Energy storage
— Switchgear protection and transformers
— Communication and control system
— Site engineering and construction cost
— Cost of Mini-Grid technology is reducing
— Cost of renewable generation and energy
storage technologies is reducing
— Increasing reliability leading to reduced
OPEX
— New payment innovations – pay-as-you-go
and mobile money
13
Regulatory Challenges
—Rural electrification agendas now feature extensively across Sub-
Saharan Africa
—Streamline regulations - unclear which regulations apply
—Electricity distribution concessions
—Cost reflective tariffs
—Plan for future growth
ACORE, 2015
15
Load Study
— Objective – 20 year power projected daily and annual hourly load
profile data
— Input for the preliminary design of a solar PV, battery, and diesel Mini
Grid for the island
— Annual power and energy forecast, daily load profile
— Number of customers per customer class
— Sales per customer class
— Analysis of the impact of Distributed Generation additions and Energy
Efficiency programmes
— Challenges for forecasting load using standard
regression analysis
16
Individual Approach to Load Forecast
Detailed site survey
Establishing work programme and development of tools
17
Present and Future Conditions
- Identifying main driver for load increase:
1. Development on the island
2. Population growth
3. Main load types
4. New electrical appliances in the houses (upgrade)
5. Occupancy rates
Present:
Future:
Scenario 1 Scenario 2 Scenario 3
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New Infrastructure Development
— STREET LIGHTS - Island length
1.7 km, One pole at 8m, LED
15W each.
— DESALINATION PLANT- 100
litres / day / person, the required
plant should be run by 15 kW to
20 kW motor
— WATER PRESSURE PUMP-
Based on the length of the island
the required size of the pump is
between 5kW and 10kW
— MARKET/SHOP constant load
level when the shop is open (9h-
21h) and when closed
19
Load Forecast Results
Annual growth 11.7% to 14.7%
2.4% 1.3%
Very high annual growthi within first 1 to 5 years
Yearly forecast for 20 years – for understanding the size for electrical installations/system
Detailed daily diagrams – for dimensioning the Mini Grid (the size of solar, wind, storage, diesel)
Typical working day: Typical weekend: Yearly Peak:
20
National Department of Tourism, South Africa
— National Department of Tourism of South Africa – renewable energy Mini Grid projects at state-
owned tourism attractions:
— Robben Island, Western Cape Province
(667 kWp)
— Hantam National Botanical Garden,
Western Cape Province (HNBG) (2.5
kWp)
— Karoo Desert National Botanical Garden,
Northern Cape Province (KNBG) (52.9
kWp)
— Free State National Botanical Garden,
Free State Province (FNBG) (52.9 kWp)