As a result of increasing environmental concerns, as well as electricity prices in South Africa,
people are beginning to take the environmental and energy problem into their own hands
through the investment and installation of their own power producing systems. This is not a
new phenomenon, but as solar photovoltaic (PV) technology is coming down in costs and
electricity prices within the country are increasing, more people will look to solar PV or other
small sized electricity generators for supplementing their energy needs while taking some
measure of action against climate change. ‘Net metering’ is the term used to describe the
method of feeding excess electrical energy onto the distribution grid from these small
systems in the residential sector. The capacity of each individual system may only be on the
order of a few kW, but on a national scale this can become a sizable contributor.
With all the effort in understanding the options for future electricity generation in South
Africa, there is little work done on understanding the scale and impact that net metering
systems will have. This work aims to fill the gap in research of this understudied aspect of the
energy system.
Research using energy models is important to developing countries. Most of the current
energy modelling software available requires a significant amount of money and learning
before they can be fully utilised. OSeMOSYS is an open source – free - energy modelling
software which has a lower learning curve, enabling a variety of researcher’s access to the
model and its components, opening up huge potential for improvement and development.
This work has two main objectives, first to create a working energy model of South Africa’s
electricity sector using the open source software; OSeMOSYS, and secondly, using this
model to understand the unstudied effects of net metered capacity within the country and how
this affects the planning of the energy sector in the future, which is done through processes
such as the Integrated Resource Plan (IRP).
Using a combination of electricity tariffs and solar PV price projections, and the Bass
diffusion model, an estimated range of the total amount of installed MW capacity of rooftop
solar PV within the residential sector of South Africa was determined. Depending on the
initial assumptions, the capacity projections start between a mere 0.4MW and 4.5MW in
2012 and grow to between 395MW and 2620MW by 2030.
The total new added capacity of energy producing technologies in the OSeMOSYS energy
model is 47.27GW between 2006 and 2030. The majority of this is supercritical coal
technology power plants, with hydro imports and peaking gas turbines mixed in. The share of
wind and solar technologies which includes concentrated solar thermal with storage
technology is 4.4% of the total capacity.