4 iN FOCuS: SmArT gridS
national electricity system, as well as the system under the control of the relevant utilities, e.g. municipalities. Any such plan will have to take the different sizes and capabilities of municipalities into account. Even without an integrated energy efficiency implementation plan, the 12% energy efficiency improvement target reflected in the Energy Efficiency Strategy of South Africa (DoE, 2005) was achieved (DoE, 2016) (Table 4-1).
Table 4-1: Energy efficiency targets and performance achieved (DoE, 2016)
Sector 2015 target
(based on the
2000 base line) Performance to 2012
Economy-wide 12% 23.7%
Industry 15% 34.3%
Residential 10% 28.2%
Commercial and
public 15% 0.3% (that is between 2003 – 2013,
electricity only)
Transport 9% 14.1% in sector-wide energy intensity Power sector 15% 26% (as per Eskom estimation)
managing energy efficiency effectively therefore implies a focus on the entire value chain, i.e. generation, transmission, distribution and the end customer – it cannot be an end customer/demand focus only. It is acknowledged that the generation of electricity and heat contributes to greenhouse gas emissions. It must also be appreciated that the electricity demand, the use of electricity and the managing of the network/grid directly contributes to the generation requirements. in the constant balance of production and consumption the efficient use of energy and the ability to leverage alternative energy options, inclusive of suitable storage capabilities, become mission critical. The various applications offered as an integral part of the smart grid solution provide the key to improved energy utilisation and to address the challenges reflected above.
Smart grid technologies fundamentally introduce a layer of digital intelligence to the grids and marry the interface between the classical grid infrastructure and the information technology capabilities. In this way the industry is enabled to respond to grid dynamics, restore power interruptions, accommodate alternative energy options, and facilitate demand response strategies.
The importance of the interdependency between policy, standards and technology must be appreciated. without an overall integrated approach and enabling policies the roll out of smart grids could result in less than optimal results.
while there are many ways in which a smart grid can be defined, the definition adopted by the South African Smart grid initiative (SASgi), as derived from the European Technology platform Smart grid (ETpSg), defines the smart grid as follows: - “A Smart Grid is an electricity network that can intelligently integrate the actions of all users connected to it – generators, consumers and those that do both – in order to efficiently deliver sustainable, economic and secure electricity supplies.”
Based on the ETpSg definition, the smart grid employs innovative products and services together with intelligent monitoring, control, communication, and self-healing technologies to:
• better facilitate and manage the connection and operation of all sources of energy;
• give consumers more choice so they can help to optimise their energy use;
• provide consumers with greater information and choice of supply;
• significantly reduce the environmental impact of the whole electricity supply system;
• deliver enhanced levels of reliability and security of supply.
in considering the objectives reflected above, it is clear that the smart grid will directly contribute to energy efficiency improvements. A smart grid provides the capability to manage the industry value chain in an integrated manner while visibility is enhanced which facilitates proactive decision-making and optimisation. The ability to introduce effective load management, demand response, real time pricing, etc. is dependent on effective customer inter- faces, grid visibility and plant/network control. It is important to note that
’integrated’ energy efficiency from a system perspective is impacted by, among others:
• The efficiency of power generation, as it links to load profile, variability and matching of supply and demand (e.g. using energy in periods of lower generation cost and resource availability, i.e. when renewable energy is abundant).
• The efficiency of the transmission and distribution grid, i.e. load and no-load technical loss reduction, reduction in line losses, transformer core losses, etc.
• The efficiency in the end use consumption of energy which is
influenced by tariffs, load control, etc. Billing and revenue recovery is also core to this as users who do not pay for energy use are unlikely to use energy efficiently.
Table 4-2 represents a consolidated perspective of smart grid-related tech- nology applications that could be pursued to enhance efficiencies in the electricity value chain. The functionalities contributing directly to energy effi- ciency include:
• Accurate loss management and loss reduction.
• Technical loss reduction, network optimisation and energy balancing.
• Capacity management and network loading.
Table 4-2: Technology applications
Business focus Functionality Enabler13 Application Revenue
management Accurate loss management and accounting
MDMS/NMS AMI/Smart meters
Targeted loss reduction and greater network visibility
MDMS/NMS AMI/Smart meters
Remote disconnect/
reconnect MDMS AMI/Smart meters
Network
management Real time network
monitoring NMS Network sensors
Fault location and
restoration management NMS Network sensors Technical loss reduction,
network optimisation, energy balancing and preventative maintenance
NMS/MDMS/
giS AMI/Smart meters/
Network sensors
Network
planning Improved capacity management, network loading, loss reduction and reliability
NMS/MDMS AMI/Smart meters/
Network sensors
Effective asset management and enhanced customer connection
NmS/giS/
MDMS NMS/MDMS/Network
sensors
Customer
service Improved customer communication (e.g.
outage management)
CiS/mdmS/
NMS AMI/Smart meters/
Network sensors Improved response time,
reduced outage time and effective power quality management
CiS/mdmS/
NMS AMI/Smart meters/
Network sensors
Reporting Regulatory, management and operation reporting (CAidi, SAidi, SAiFi, etc.)14
NMS AMI/Smart meters/
Network sensors Accurate fault reporting
and fault/equipment history
NMS AMI/Smart meters/
Network sensors Capture detailed network
information NMS
13 MDMS: Meter Data Management System.
NMS: Network Management System.
AIM: Advanced Metering Infrastructure.
giS: geographic information System.
14 CAidi: Customer Average interruption duration index.
SAIDI: System Average Interruption Duration Index.
SAiFi: System Average interruption Frequency index.
From the above it is clear that there are numerous opportunities to improve energy efficiency through the deployment of smart grid technology applications. Energy efficiency as a specific objective should however be included in the current assessment and benefit realisation criteria of smart grids in South Africa.