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Trends and statistics of Solar PV Distributed Generation in South Africa
by Aradhna Pandarum, Sustainability Division, Eskom Research, Testing and Development
Abstract
Rising electricity prices, awareness on the need for reduced greenhouse gas emissions, and decreasing technology costs
have made investment into small scale embedded generation more attractive to many end-user consumers (residential,
commercial, industrial). Such installations are already commonplace in industrialized economies but developing
countries, such as South Africa, are now observing a similar emerging trend as presented in this article. The installations
reported about in this paper have electrical capacities ranging from 1kW to 5MW and as such installations continue to
increase, the impacts are felt by multiple stakeholders across the energy sector. Such stakeholders include electricity
distributors, municipalities, industry (manufacturers and installers), electricity system planners, the national grid
operator, as well as policy-makers.
Introduction
Solar PV is being considered the fastest growing power-generating technology in the world. Figure 1 below illustrates
the small scale solar PV penetration in various parts of the world together with the percentage of total generation
capacity installed in those areas [1,2], Germany has the highest penetration in the world for small scale PV totaling
38.25GW.
Fig. 1: Installed capacity of small to medium scale solar PV in different parts of the World [1, 2]
South Africa has been experiencing an increase in consumers who have shifted to this technology from 1992 [3]. This
trend is visible across all segments of consumers including industrial, agricultural, commercial and residential
consumers. As battery storage costs continue to decline (forecasted to be between 50% - 66% decline [4]), rooftop solar
PV will provide an increasingly attractive business case as an intervention for backup supply when the electrical grid is
not available. Many companies such as South African Photovoltaic Industry Association (SAPVIA), Greencape and
South African Local Government Association (SALGA) make assumptions of the penetration levels with limited data to
justify their assumptions. SALGA reported that there was ~38.3MWp of rooftop PV installed in 2016 [5] whilst
Greencape stated that there is more than 94MW currently installed [6]. However, these numbers are questionable as it is
only based on one source of data and/or assumptions made. There is therefore a need to establish the collection,
verification and validation of such statistics. The current statistics represented in this paper do indicate that the rapid
growth of PV rooftop is a reality in South Africa. As long as there is no official SSEG registration process for low to
medium voltage connected customers in place, uncertainty about these numbers will remain.
The National Energy Regulator of South Africa (NERSA) and the German Development agency (GIZ) have confirmed
that they will be initialising a formal national registration process for SSEG, however, it is envisaged that this process
will only be operational in the next 2 to 3 years. In the interim, certain municipalities and Eskom have taken the
initiative to establish their own registration processes that allow connection to their distribution. The South African
Department of Energy (DoE) has released a Schedule 2 to the Electricity Act of 2006 [7] on 10 November 2017, which
states that customers are exempt from licensing of small scale embedded generators (capacity of <1MW) after
installation, however, with the requirement of having to register with NERSA. This regulation now enables customers
to install small scale embedded generators without having to acquire a generating license from NERSA. The
registration of such generators is however mandatory and it is assumed that the registration process mentioned above is
still applicable and enforceable to installations completed prior to the implementation of the national registration
process.
This article estimates the rooftop PV Embedded Generation (EG) installations from 2003 to December 2017 based on
the information collected from 3 sources namely: Power Quality Renewable Service (a South Africa firm that tracks
such installations), municipalities with a formal registration process for these installations and Eskom. These
installations impact various stakeholders on several levels in terms of revenue loss to municipalities and distributors,
impact on the electricity grid and system operations in terms of forecasting residual load and the accuracy of short and
long term net demand forecasts. As more South African customers install rooftop PV, the following engineering
challenges could surface:
New challenges around voltage variations due to there being a reverse power flow experienced and
Thermal stress of distribution networks which can result in a need for increased maintenance, higher risk in terms of
safety and protection etc. [8]
There are currently 34 municipalities in South Africa which have an approved registration process designed for the
registration of small scale embedded PV installations. Seven municipalities have NERSA approved net-metering tariffs
and these are presented in Table 1. These tariffs demonstrate that municipalities are in fact allowing export of energy
into their distribution grids and compensating their customers accordingly thus strengthening the business case for
customers who wish to install solar PV. This also motivates the consumer to register with the municipality to qualify for
such tariffs.
Municipality Net-metering scheme
City of Cape Town 70.08c/kWh for every kWh exported
Theewaterskloof 48c/kWh for every kWh exported
EThekwini 68c/kWh for every kWh exported
City of Tshwane 10c/kWh for every kWh exported
City Power 36.14c/kWh - 42.79c/kWh for every kWh exported
Nelson Mandela Bay Offsetting the tariff of the customer
Overstrand 65.25c/kWh for every kWh exported
Table 1: Net-metering schemes used in Municipalities [9]
Current status
Overview
Data received from various sources shows that there is approximately 285MWp (DC) [10] of small scale solar PV
(rooftop and ground-mounted) installed in South Africa as at December 2017. This figure is calculated using the data
received from PQRS (212MWp as of September 2017[11]), municipalities (approximately 50MVA [12]) and Eskom
registered installations (39MWp [13]) with further removing duplicates. The total number of installations equates to
approximately 139,556 systems. The installed capacity of small to medium scale solar PV installations results in a
market share percentage of 0.65% of the total national generation capacity of 44.134GW [14]. There are only 87 150
off-grid systems with a resultant installed capacity of 14.35MWp representing 5% of the total installed capacity. A
depiction of the yearly growth from 2003 to 1 December 2017 is represented in Figure 1, where the green bar represents
the increase in installed capacity each year. It can be seen from the figure that installations have been accelerating
especially over the last 5 years – a trend that is likely to continue due to the factors supporting the growth such as
increasing tariffs and decreasing technology costs.
Fig. 2: Yearly analysis of total installed capacity (MWp) [10-13]
Sectorial Analysis
Figure 2 and Figure 3 illustrates the total installed capacity and number of installations in each province per sector,
respectively. The highest penetration of these installations exists in Gauteng and the Western Cape, predominantly
owning to the market share in the commercial and industrial sector. This is mainly due to the fact that these provinces
contribute to the greater part of economic activity as most businesses are generally based in these provinces. The
commercial and industrial sector contributes to 69.8% of the total installed capacity, followed by a 22.5% contribution
to total installations from the agricultural sector and 7.7% from the residential sector. The contributing reason as to why
commercial customers migrate to solar PV, is that their electricity demand profile follows a similar profile as the solar
PV production profile resulting in the most value for money. Other factors for adoption of embedded small scale solar
PV can include ability to have more predictable electricity costs over the long term as well as large roof space
availability on buildings or land area on corporate campuses.
Fig. 2 Total capacity installed (MWp) in each sector per province [10-13]
Fig. 3 Total number of installations in each sector per province [10-13]
The charts above demonstrate that the growth in the small scale market for solar PV is not necessarily installed in
provinces with the highest solar irradiation resource which are Northern Cape, Eastern Cape and Northwest Province
The embedded solar PV market, however, is determined by different drivers including: current tariffs applicable to
those customers, feed-in tariffs available, energy demand profile, power purchase offerings and available land or
rooftop area. These markets factors are reflected in the statistics below where the commercial centres of South Africa
host the majority of small scale solar PV installations. The overall sub-sector distribution of these installations is
depicted in Figure 4. The sub-sectors which contribute most to the penetration of embedded Solar PV generation are
retail followed by offices and irrigation.
Fig. 4 Sub-sector analysis penetration for the various sectors [10-13]
Future Growth
The current drivers for further growth of small scale solar PV are expected to remain at least over the medium term of
5-10 years. This is reflected in the expected growth for the uptake of small to medium scale solar PV for years 2018-
2025 as represented in Figure 5. This figure, derived from a model built by System Dynamics in R, T & D, illustrates
that by 2025 there will be an installed capacity for small to medium scale solar PV of 2.33GW [15]. This model was
built to incorporate the drivers that lead to low payback periods for the installation of such technology.
Fig. 5 Growth in capacity (MWp) for small to medium scale PV from 2018 to 2025[12]
Conclusion
As the increasing trend of installed small-scale embedded generation continues, utilities and distributors need to
position themselves for this emerging evolution. This will require more accurate tracking of such installations to ensure
a deeper understanding of the future customer. The aggregated impact of the current penetration of these installations is
already becoming visible to the national system operator indicating a predicament being faced. A better system
management interface is required to ensure that the system operator has oversight and controllability of these
installations. There are various technologies that are currently emerging, in both cost and technological maturity, such
as fuel-cell and storage systems that will further accelerate the penetration of small scale solar PV. It is no doubt that
customers are beginning to realize the benefits of installing such technology and this trend is only to increase. The
current decisions and business models formulated by utilities and distributors will require drastic changes due to the
impact of such installations onto the distribution grid.
References
[1] MaltiGoel, “Solar rooftop in India: Policies, challenges and outlook,” Green Energy & Environment, vol. 1,
no. 2, pp. 129-137, 2016.
[2] T Ackerman, E Tröster, P Schierhorn, J Schmidt, B Narasimhan, J Gaebler, H Bhatnagar, S Goel, F Huebner,
“Rooftop PV in Indian Electricity Distribution Networks,” 2017.
[3] SAPVIA, "South Africa Solar Energy Technology Road Map - Solar PV," 2013.
[4] Electricity Storage and Renewables: Costs and Markets to 2030 – IRENA, 2017.
[5] SALGA, “Status of Small Scale Embedded Generation (SSEG) In South African Municipalities,” 2016.
[6] Greencape, “Greencape - Solar PV,” [Online]. Available:
https://www.greencape.co.za/content/focusarea/solar-pv. [Accessed 2018].
[7] South Africa Gazetted DOE, "Electricity Regulation Act 2006 - Schedule 2, Licensing Exemption &
Registration Notice," 2017.
[8] M. Farhoodnea, A. Mohamed, H. Sharreef and H. Zayanderhoodi, "Power Quality Analysis of Grid-Connected
Photovoltaic Systems in Distribution Networks," 2013.
[9] Municipalities, Tariff Book, 2017.
[10] A. Ramdeyal, "Small to Medium Scale Embedded Generation Solar Photovoltaic (PV) Power Penetration in
South Africa," Eskom Research, Testing and Development, Rosherville, 2018.
[11] PQRS, Procured database for SSEG PV, 2017.
[12] Municipalities, Collation of data from various municipalities, 2017.
[13] Eskom, Database of registered SSEG PV systems, 2017.
[14] Eskom, “Eskom Integrated Report,” 2017.
[15] N. Mamela and N. Sibeko, "Long Term role of Renewables Simulator," Eskom Research, Testing and
Development, Rosherville, 2018.
Contact Aradhna Pandarum, Eskom Research, Testing and Development, Tel (011) 629 5950, [email protected]