Scenarios of energy supply and associated water demands · Scenarios of energy supply and associated water demands Amos Madhlopa, Mascha Moorlach, Debbie Sparks, Samantha Keen and

Scenarios of energy supply and associated water demands

Amos Madhlopa, Mascha Moorlach, Debbie Sparks, Samantha Keen and Pieter Krog

September 2014

Key points

� Eleven scenarios of energy supply in South Africa were used to investigate scenarios of the associated demand of water in 2030 and 2050.

� The scenarios considered were Constant Emissions, Moderate Decline, Advanced Decline, Carbon Tax, Carbon Budget, Rooftop PV, Big Gas, High Nuclear Cost, High Coal Cost, Solar Park and Restrained Learning Rate.

� National data was used to analyse water usage associated with the established annual energy supply.

� There is an increase in electricity generation between 2030 and 2050.

� The share of renewable energy also increases between the two time periods.

� For each scenario, water usage decreases between the two time horizons except for the Higher Nuclear Cost scenario.

� All the considered scenarios (except Higher Nuclear Cost) have the potential to reduce water usage in the energy sector.

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This project was commissioned by the Water Research Commission

Suggested citation for this paper:

Madhlopa, A, Moorlach, M, Sparks, D, Keen, S & Krog, P. 2014. Scenarios of energy supply

and associated water demands. Draft report for submission to the Water Research Commission. Energy Research Centre, University of Cape Town, Cape Town.

Energy Research Centre University of Cape Town Private Bag X3 Rondebosch 7701 South Africa Tel: +27 (0)21 650 2521 Fax: +27 (0)21 650 2830 Email: [email protected] Website: www.erc.uct.ac.za

Contents

Executive summary iv

1. Introduction 1

1.1 General 1

1.2 The South African context 3

1.3 Study objective 7

2. Methodology 7

2.1 Timescale of analysis 8

2.2 Data collection and processing 8

3. Findings and discussion 10

3.1 Climate change and mitigation 10

3.2 Technology-specific scenarios compared to Moderate Decline 14

3.3 Restrained learning rate 19

3.4 Inter-comparison of water requirements for scenarios 21

4. Concluding remarks 23

References 25

Appendix: Data on capacity of technology options under different scenarios

considered in this investigation 27

Executive summary: Scenarios of energy supply and associated water demands iv

ENERGY RESEARCH CENTRE

Executive summary Climate change is one of the major challenges of the 21

st century. Consequently, different

countries are making policy shifts to mitigate the impacts of this environmental problem, and South Africa is no exception. At present, the major source of energy in South Africa is coal,

which contributes to carbon emissions and hence climate change. In view of this, the country needs to make a transition to low-carbon sources of energy. Water is required in the production

chain of energy, but South Africa is a water-stressed country, with water resources that are increasingly being placed under pressure. It is therefore important to minimise the water demand in the energy and other economic sectors.

The supply of energy under different scenarios has been reported in previous work. For instance, the Integrated Resource Plan (IRP) of 2011 and the IRP draft update of 2013 articulate different scenarios of energy supply in South Africa in time-frames up to 2030 and 2050 (DoE 2013). The electricity plan plays a vital role in promoting sustainable development. Water is recognised as a key constraint and risk in the provision of energy, especially in the face of climate change. With the above in mind, the objective of the current investigation is to analyse the implications of various energy scenarios on water resources.

To perform a scenarios analysis of the water demand associated with energy production in future, time horizons of 2030 and 2050 were adopted in conformity with the range reported in

literature on scenarios analysis at international level (Saisirirat et al 2013; Promper et al 2014), and the available local data on energy projections (DoE 2013). Eleven energy scenarios from the updated IRP of 2013 were considered: Constant Emissions, Moderate Decline (in carbon emissions), Advanced Decline (in carbon emissions), Carbon Tax, Carbon Budget, Rooftop photovoltaic (PV), Big Gas, High Nuclear Cost, High Coal Cost, Solar Park, and Restrained

Learning Rate. Annual water usage was calculated, using an Excel spreadsheet, for each energy technology option under a given scenario. The energy technology options covered in this report are: new coal, existing coal, combined cycle gas turbine, open cycle gas turbine/gas engines,

hydro imports, hydro domestic, pumped storage, nuclear, solar photovoltaic, concentrated solar power), wind and others. The total water usage was computed for each scenario.

Results show that there is a general increase in electricity generation between the two time horizons. The share of renewables in the generation of electricity for each scenario also rises between 2030 and 2050. In addition, the Big Gas scenario exhibited the lowest demand for

water in both 2030 and 2050 time horizons. The demand for water decreases between the two time horizons except for the Higher Nuclear Cost, in spite of the increasing electricity production. A higher share of renewable energy, especially solar PV and wind, can assist in bringing down the demand for water in the energy mix.

Scenarios of energy supply and associated water demands 1


1. Introduction The objective of this investigation is to analyse the implications of various energy scenarios on water resources. Different future scenarios are examined in order to get a greater understanding of energy demand and supply over time to 2050. This introductory section presents general issues, including scenarios analysis, climate change and mitigation as well as energy and water. It also places the study in a South African perspective, by considering the local context. Section 2 presents the methodology, Section 3 the findings and discussion, and Section 4 the concluding

remarks. Technical data are provided in the appendix.

1.1 General

1.1.1 Scenarios analysis Scenarios are theoretical propositions which describe future possible pathways, and are important tools for decision-making about choosing options under specific hypothetical situations. They commence by examining the present state and go on to give a final state in the

future at a fixed time horizon. Scenarios aim at: (a) modifying the way of thinking, and creating a common vision; (b) supporting the process of decision-making; (c) managing risk and uncertainty; and (d) learning and understanding (Ravindra & Iyer 2014). It is important to remember that scenarios do not attempt to predict events but provide alternative futures and

their connections (Mannermaa 1991; Kahanem 2012).

Scenarios analysis finds application in planning energy and other public service systems where several options and situations may exist. Planning of energy needs a proper balance between the

supply and demand of energy in a given locality or region. For instance, Raele et al (2014) investigated the scenarios for second-generation ethanol in Brazil. Their work contributed

scenarios that can be used in the development of public policy and as a tool for decision makers working in the energy sector. Ravindra and Iyer (2014) developed a scenarios framework for identifying and assessing the impact of different decentralised energy options at a community level. They applied the proposed framework to an urban residential community (Vijayanagar, Bangalore in India). They found that liquefied petroleum gas-based and combined heat power microgrid and proactive demand response by the community is the appropriate option that enabled the community to meet its energy needs in a reliable and cost-effective way.

Scenarios analysis has been extensively used to map out and understand options for mitigation

of climate change. For instance, a scenario framework for long-term mitigation of climate change was defined by the Energy Research Centre at the University of Cape Town (ERC

2007). It comprised five possible pathways: Growth Without Constraints, Current Development Plans, Can Do, Could Do, and Required by Science – see Figure 1-1, which makes it evident that the Growth Without Constraints pathway leads to a dramatic rise in carbon emissions, with

the Required by Science pathway being the lowest.

Van Vuuren et al (2014) developed a new scenario framework for research into climate change. The aim of this framework is to foster collaboration amongst climate change researchers from wide range of perspectives and spectrum disciplines to develop scenarios that are relevant to policy and decision making regarding climate change.



Figure 1-1: Scenarios framework for mitigation of climate change in South Africa Source: ERC (2007)

1.1.2 Climate change and mitigation Due to human activities, excess quantities of greenhouse gases (GHGs) are being emitted into

the atmosphere. The primary gas involved is carbon dioxide (CO2), which is released during the transformation and combustion of fossil fuels. CO2, methane (CH4) and nitrous oxide all contribute to climate change. Although it is natural to find these gases in the atmosphere,

excessive concentrations of them is of concern (Winkler, 2005).

The case for anthropogenic climate change is strong, and global efforts have been made to

reduce the risks. One of the main global organisations involved in mitigating climate change is the United Nations Framework Convention on Climate Change (UNFCCC), with the objective of ‘preventing “dangerous” human interference with the climate system’ (UNFCCC, 2014a).

Although the efforts of the UNFCCC in mitigating climate change have been in many ways successful, the reality is that climate change will continue. The level of impact is, however, still uncertain. Climate change has associated potential for increases in natural disasters – extreme droughts and excessive floods. Extreme droughts serve as a reminder that water is a limited

commodity that should be closely monitored. In this regard, it is important to take into account the impact of climate change on water resources when planning various economic activities of a country, including the energy sector.

1.1.3 Energy and water Climate change is one of the global challenges of this century. In this vein, previous studies

show that anthropogenic activities are generating GHGs and energy consumption is the main contributing factor to climate change (Saikku et al 2008; Akhmat et al 2014). In particular, the burning of fossil fuels is increasing the concentration of GHGs in the atmosphere. This is

exacerbated by population and industrial growth which is increasing the demand for energy. Moreover, these resources occur in finite quantities, and so will eventually be depleted. Energy is the main driver of an economy, and economic growth is perceived to be unsustainable if it demands a lot of energy, generates significant pollutants, and negatively affects public health (Abdallah et al 2013). In contrast, renewable energy resources do not draw on a fixed stock, and replenish themselves by natural mechanisms, and are therefore one of the promising pillars of sustainability in the production and consumption of energy.

Energy security is another important factor to consider when planning energy supplies to meet specific demand levels. Properties of energy security include stability, flexibility, adequacy, resilience and robustness (Gracceva & Zeniewski 2014). An energy supply chain needs to have

all these properties to be secure. For instance, the fact that there are limited reserves of fossil fuels renders them insecure. Exploitation of renewable energy can contribute, not only to the

mitigation of climate change, but also energy security. The inclusion of renewable energy in the energy mix requires proper planning in order to achieve the desired outcomes.



Water plays a vital role in the production chain of energy, as shown in

Figure 1-2. It is used in fuel acquisition (fa) and processing (fp), plant construction (pc), power generation (pg), power transmission (pt) and plant decommissioning (pd). At each stage of the energy production chain, a volume (W) of water is withdrawn from a reservoir. Part of this quantity of water may be consumed (C), recycled (R) or discharged back into the reservoir (D).

For example, water is required during mining, processing and transportation of coal, while thermoelectric power plants need water for steam generation and wet-cooling during electricity generation. So, the demand for water would increase with the amount of energy produced,

depending on the energy technology option. Fossil fuels withdraw a large volume of water over the life-cycle of energy production, especially for thermoelectric power plants operated with a wet-cooling system (Fthenakis & Kim 2010). The concern for water demand in the energy production chain is significant in regions with limited water resources. Moreover, it is reported that climate change will affect water availability, with some areas experiencing a reduction in water supply (Charlton & Arnell 2011; Kiem 2013). In view of this, there has been growing interest in assessing water requirements for energy production, and scenarios analysis can play a vital role in this direction.

Figure 1-2: Energy production chain

1.2 The South African context The major source of energy in South Africa is coal, but the country cannot continue to rely heavily on coal without serious negative impacts on the society, environment, health and

economy. Therefore, South Africa is making some policy shifts towards sustainable energy. In this respect, renewable energy is perceived to be more ‘friendly’ to the environment (with low or zero carbon emissions) and secures energy supply for present and future generations. Energy

technologies exhibit varying needs for water in the energy production chain. However, South Africa is a water-stressed country with water resources that are increasingly being placed under



pressure (Colvin et al 2009; DWA 2013), making it necessary to minimise water withdrawal for the energy and other economic sectors.

South Africa is diversifying the sources of energy to promote sustainable development. In this

vein, the government formulated an integrated resource plan (IRP) to develop a sustainable electricity investment strategy for generation capacity and supporting infrastructure for South

Africa over the next 20 years (DoE 2013). The plan developed scenarios characterised by combinations of assumptions and constraints, for instance, varying GDP growth, primary resource availability and price and limits on CO2 emissions, which resulted in contrasting cost

optimal capacities of existing generation technologies. The generation technology options that were considered in the scenarios analysis included existing coal, new coal, combined cycle gas turbine (CCGT), open cycle gas turbine (OCGT)/gas turbine, hydro imports, hydro domestic, pumped storage (PS), nuclear, photovoltaic )PV), concentrated solar power (CSP), wind and other. The cost optimal combination of these technology options was determined for the following scenarios in the 2013 update of the IRP:

1. Technology options arising from the three emission options in 2030 and 2050 considered

under the following three scenarios (Figure 1-3):

a) Constant Emissions: In this scenario, carbon emissions would be made at a constant rate of 275 million tons per annum (DoE 2013). This scenario does not meet the

requirements of the DoE of Peak-Plateau-Decline in the levels of emissions but it acts as an assumption over the Base Case.

b) Moderate Decline: In this scenario, carbon emissions start to decline from the established 275 million tons per annum at a moderate rate in 2037 before reaching a target of 210 million tons per annum in 2050.

c) Advanced Decline: This scenario is aimed at achieving an early reduction in carbon emissions from the IRP 2010 limit of 275 million tons per annum in 2030 before declining at an increasing rate to 140 million tons per annum in 2050.

Figure 1-3: Emission trajectory scenarios for the IRP 2010 update Source: DoE (2013)

2. Technology options arising from the carbon tax relative to emissions caps

To evaluate the impact of the carbon tax on the electricity sector in the IRP (DoE 2013), it was assumed that the electricity industry was granted a 60% exemption on the full carbon tax until

2019 after which this tax-free allowance is annually reduced by 10% until it is eliminated in 2025. This effectively translates to a carbon tax of R40/ton in 2015 increasing gradually to



R47/ton in 2019 before the more rapid escalation to R117/ton in 2025. Under this scenario, there is insignificant reduction in carbon emissions (Figure 1-4).

Figure 1-4: Electricity industry carbon emissions under the Carbon Tax scenario Source: DoE (2013)

3. Technology options arising from the updated IRP’s carbon budget scenario relative to the

advanced decline (DoE 2013)

In this scenario, the total emissions allowance for the electricity industry is fixed over a specific period and is imposed as a constraint. A comparison of the emissions under the carbon budget

and advanced decline scenarios is presented in (Figure 1-5).

Figure 1-5: Electricity industry carbon emissions under the Advanced Decline and Carbon Budget scenarios

Source: DoE (2013)

4. Technology options arising from IRP Rooftop PV case relative to the Moderate Decline

scenario.

As the cost of photovoltaics (PV) decreases, it is highly likely that the generation of electricity from PV will increase. The realisation of PV electricity generation can take place in the commercial and residential sectors, and to some extent in the industrial sector.

Many forms of embedded generation exist (wind, biogas and biomass), but for the purposes of this scenario, the IRP report considered only the roll-out of residential PV as a proxy for

commercial and industrial PV. The assumed penetration of this small-scale PV capacity that was exogenously imposed on the IRP model is shown in Figure 1-6. This is based on the



assumption of 50% of households of LSM7 and above investing in 5 kWp of capacity each by 2020.

Figure 1-6: Possible small-scale PV capacity Source: DoE (2013)

5. Technology options arising from the Big Gas scenario.

There is great potential for exploitation of offshore and shale gas in South Africa. This scenario considers large-scale exploitation of shale gas, which can result in a decrease of gas price, and a switch from coal and nuclear to gas.

6. Technology options arising from the High Nuclear Cost scenario

Nuclear power is attractive due to environmental policies that support low-carbon economic pathways, and strategic considerations that relate to the curtailment of the dependence on fossil

fuels (Mari 2014). Nevertheless, there is some uncertainty about the cost of nuclear technology, with a range of $3 800/kW to $7 000/kW (DoE 2013). This scenario considers energy supply with a high cost of nuclear energy ($7 000/kW).

7. Technology options arising from the High Coal Cost scenario

South Africa is endowed with abundant coal resources, which translates into lower costs for coal-fired technologies relative to other power-generating technologies if externalities or cost of carbon are not considered. The base case of the IRP assumes R350 per ton for new coal-fired generation. For the High Coal Cost scenario, R500 per ton is assumed for new coal-fired generation, but the price for discard coal as used by fluidised bed combustion technology (FBC) remains at R150 per ton. The lower discard coal price results in slightly higher coal-fired

capacity for the High Coal Price scenario in 2030 relative to the Moderate Decline scenario because the model needs capacity earlier and can build FBC. FBC capacity is likely capped in the IRP model and therefore the High Coal Price scenario results in less coal-fired capacity by

2050 and more gas-fired capacity.

8. Technology options arising from the Solar Park test case.

South Africa possesses one of the most abundant solar resources in the world (Donev et al

2012), especially in the Northern Cape, which can support the exploitation of concentrated solar power (CSP) in the solar corridor. The Moderate Decline scenario delays the construction of

CSP until 2030 but the idea of a Solar Park test forces construction to take place earlier, allowing for 1000 MW of CSP construction each year from 2018 to 2022. This results in the delay of the delay of the construction of a nuclear power plant in the Moderate Decline scenario

from 2025 to 2030.

9. Technology options arising from the learning rate scenario.

The cost of manufacturing a technology tends to decrease with increasing experience. It is

common to accumulate more knowledge and skills about a given technology as time passes by. In the case of energy technologies, the learning rate plays a vital role in the mitigation of climate change (McDonald & Schrattenholzer 2001). Cheaper energy technologies are more attractive



to invest in than expensive ones. In this regard, energy technologies with a high carbon footprint easily attract funding as long as the cost is low. Consequently, technology learning is an important factor in in the analysis of scenarios for future energy supply systems. Technology

learning rates are a function of global installed cumulative capacity, and have been studied for South Africa (Winkler et al 2009) and are integrated in ERC’s energy modelling (ERC 2013a).

The Base Case of the IRP assumed aggressive learning rates for all technologies except coal, including modest learning for nuclear and aggressive learning for PV (so far realised in the REIPPPP), and for CSP (not yet attained in the REIPPPP) (DoE 2013). A Restrained Learning

Rate scenario was developed for the IRP update for comparison to the Base Case. In the Restrained scenario no learning was assumed for nuclear, biomass, IGCC and wind, with more restrained learning for CSP and PV until 2020 after which learning was assumed to cease. The variation of normalised learning rates for nuclear, biomass, CSP, IGCC, PV and wind technologies is presented in Figure 1-7.

Figure 1-7: Technology cost paths under the base and restrained scenarios Source: DoE (2013)

1.3 Study objective The updated IRP recognises the need to reduce water consumption as an important factor for sustainable development. However, there is limited analysis of the water withdrawal for various energy scenarios. The objective of this study is, therefore, to analyse scenarios that reflect various energy sources and water demand to ensure a balanced and efficient water use in South Africa. At the core of these scenarios is the projection of energy demand and renewable energy supply over specified time horizons.

2. Methodology The updated IRP electricity scenarios provide an important tool for policy and decision making. It was therefore decided to adopt these scenarios, for this study, as spanning the likely range of possible outcomes for future electricity generator expansion. To analyse the water demand under these energy scenarios, the following steps were followed:

1. setting a time scale of the scenarios analysis; 2. collecting relevant data; and 3. analysis of the data.



2.1 Timescale of analysis In order to have meaningful comparison, the timescales need be chosen in conformity with the existing future scenarios pertaining to development plans or climate change models (Promper et al 2014). There are many examples in the literature which support the time periods chosen in

this study. For example, Saisirirat et al (2013) analysed the penetration rate of electric vehicles in Thailand, using a time period of 2010-2030. Marco et al (2014) also set a time horizon of 2030 to estimate crown defoliation of twelve tree species in Europe, under three climate and one

nitrogen scenarios, while Promper et al (2014) chose three different time periods (2030, 2050 and 2100) to investigate landslide risk scenarios in Austria.

In the present work, consideration was given to meaningful time horizons for which data would be available. It is helpful to consider both the medium and long terms. In the medium term (considered as 2030) much infrastructure investment will happen. The change needed for a low-carbon transition and for large energy systems to change, may go into the long term (2050). The long term provides a more flexible time frame with many possibilities. The available scenarios

for climate change and energy in South Africa have been documented for time periods 2030 and 2050 (DoE 2013). These time horizons are within the range reported in literature on scenarios

analysis at international level, and were consequently adopted in the present investigation. A summary of the considered scenarios is given in Table 2-1.

Table 2-1: A summary of scenarios analysed in this report

Scenario symbol Scenario description

CE Constant Carbon Emissions

MD Moderate Decline In Carbon Missions

AD Advanced Decline In Carbon Missions

CT Carbon Tax

CB Carbon Budget

PV Rooftop PV Case

BG Big Gas

HN High Nuclear Cost

HC High Coal Cost

SP Solar Park

LR Learning Rate Scenario

2.2 Data collection and processing Data were collected from government reports and other publications, using a desktop approach.

These documents were obtained from the internet, library and other sources. The data were predominantly extracted from the updated IRP (DoE 2013). It should be noted that these data

were generated under various appropriate assumptions (not replicated in this report) with robust modelling tools and review processes.

Water requirements of energy technologies vary significantly in terms of their water withdrawal

and consumption. Various methods for the estimation of the amount of water used per unit of energy output have been developed. The unit of water intensity used in the IRP is litres per megawatt hour (l/MWh). Consequently, to enable comparisons, the volume of water for energy production is estimated in litres in this study.

When a certain amount of water is withdrawn from a reservoir, part of it is consumed while the remaining portion is discharged into the reservoir. In view of this, it is important to note whether the reported volumes of water are for water withdrawal or water consumption. Water

usage factors for different energy technology options were used to compute the corresponding amounts of water. Each technology withdraws a certain amount of water at different stages in the energy production chain. The quantity of water withdrawn (Wi) would depend on the



amount of energy (Ei) supplied by a given technology. So, the total volume of water withdrawn (W) by the various energy technologies deployed was computed from:

W = i = 1 (1)

where fi is the water withdrawal factor for a given technology (l/MWh). In practice, water withdrawal factors are constant for a specific energy technology and stage of electricity

generation (Fthenakis & Kim 2010). The amount of energy supplied (MWh) was calculated from:

Ei =NdNhkiPi (2)

where ki is the capacity/load factor of the energy technology, Nd is the number of days in a year (365), Nd is the number of hours per day (24), and Pi is the installed capacity of the technology (MW). The various water and capacity factors used in the computation are presented in Table 2-2..

Table 2-2: Water usage and load factors

Technology option

Water factor * (litre/MWh)

Load factor **

(%)

Existing coal 231 85

New coal 43 85

CCGT 19.2 50

OCGT / Gas Engines 19.8 10

Hydro imports 0 67

Hydro domestic 0 1

Pumped storage (PS) 0 1

Nuclear 0 92

PV 15 19

CSP 310 47

Wind 0.79 30

Other 0 1

*Water factors: All factors from IRP update report (DoE 2013) except for 1) PV from Fthenakis & Kim (2010). 2) Wind from Madhlopa et al (2013). 3) It should be noted that, for a given technology, there are variations in the water

intensities reported in literature (Madhlopa et al 2013). In addition, the IRP update report does not specify whether the reported factors are for water withdrawal or consumption.

**Load factor: All factors from IRP (DoE 2013) except for:

1) Hydro domestic, PS and Other: estimated.

In this study, the share of renewable energy (RE) in the scenarios was based on the RE technologies (imported and domestic hydro power, pumped storage, solar PV, CSP and wind) considered in the IRP energy scenarios analysis. All the calculations were performed by using an Excel spreadsheet. An example of the spreadsheet is shown in Figure 2-1.



Figure 2-1: Spreadsheet for calculating water usage for the Constant Emissions, Moderate Decline and Advanced Decline scenarios

3. Findings and discussion

3.1 Climate change and mitigation

Table 3-1 shows the electricity production of technology options under the Constant Emissions,

Moderate Decline and Advanced Decline scenarios. It is observed that the annual generated electricity is the same in 2030, which is ascribed to the fact that there are insignificant differences in the plant capacities for a given technology when considered under the three

different scenarios. There is an increase in the total annual energy production under each scenario between the two time periods, probably due to population and industrial growth

(increases of 34%, 34% and 35% for Constant Emissions, Moderate Decline and Advanced Decline scenarios respectively). Electricity generated is notably higher under the Advanced Decline scenario, but only by 2050. This indicates that the stress on water resources would be elevated unless the technology mix and generation technologies themselves were to become more water efficient.



Table 3-1 Total annual energy generation under different technology options as in Constant Emissions, Moderate Decline and Advanced Decline scenarios.

Technology option

2030 2050

Constant Emissions (MWh)

Moderate Decline

(MWh)

Advanced Decline

(MWh)

Constant Emissions

(MWh)

Moderate Decline

(MWh)

Advanced Decline

(MWh)

Existing coal 269 768 580 269 768 580 269 768 580 120 029 520 120 029 520 120 029 520

New coal 18 242 700 18 242 700 18 242 700 183 916 200 94 564 200 38 719 200

CCGT 15 549 000 15 549 000 15 549 000 27 988 200 40 427 400 37 317 600

OCGT / Gas Engines

6 727 680 6 832 800 6 727 680 10 722 240 9 986 400 9 986 400

Hydro imports

17 528 760 17 528 760 17 528 760 17 528 760 17 528 760 17 528 760

Hydro domestic

60 444 60 444 60 444 60 444 60 444 60 444

Pumped Storage

254 040 254 040 254 040 254 040 254 040 254 040

Nuclear 53 674 272 53 674 272 53 674 272 103 157 760 167 631 360 232 104 960

PV 16 603 528 16 365 607 16 416 590 42 486 000 42 486 000 42 486 000

CSP 13 528 944 13 528 944 14 758 848 33 207 408 44 686 512 48 786 192

Wind 11 458 080 11 169 000 11 904 840 27 646 560 28 067 040 28 303 560

Other 56 064 56 064 56 064 0 0 0

Total 423 452 093 423 030 211 424 941 818 566 997 132 565 721 676 575 576 676

Figure 3-1 below shows water demand under the Constant Emissions, Moderate Decline and Advanced Decline scenarios for the two time periods considered (viz. 2030 and 2050). There is no distinct difference in water requirements amongst the three scenarios in 2030. This is

attributed to the fact that all the three scenarios have the same corresponding capacity for all the technology options (except OCGT/gas engines, PV and wind). However, there is a decline in water requirement for all the scenarios (30, 30 and 33% for the Constant Emissions, Moderate Decline and Advanced Decline scenarios respectively) between the two time periods. The Advanced Decline scenario exhibits the lowest water demand in 2050, which is a positive trend, and is explained by the increase in nuclear energy (about 40% of the annual energy is generated by nuclear power plants), which predominantly uses seawater and insignificant impacts on fresh

water resources.

Figure 3-1: Annual water requirement for energy production under Constant Emissions, Moderate Decline and Advanced Decline scenarios

0

1

2

3

4

5

6

7

8

2030 2050

Wate

r usage (

x10

10

litre

)

Year

Constant Emissions

Moderate Decline

Advanced Decline



The National Treasury’s current proposal introduces a carbon tax from 2015, increasing the threshold by 10% per annum until 2019. In real terms, the 2015 carbon tax will effectively stand at R40/ton. From 2020 and onwards, the carbon tax becomes more aggressive and will reach

R117/ton by 2025.The application of the emissions limit in the IRP 2010 and the IRP Update provide a more significant carbon price than the carbon tax. This highlights the point that, as a result of the emissions limit (including potential declines), the IRP modelling chooses a more aggressive decarbonisation pathway than the proposed carbon tax and consequently consideration should be given to using one of the two but not both.

Table 3-2 shows the technology options under Constant Emissions and Carbon Tax scenarios. It is observed that that the total annual energy production under the Carbon Tax is slightly lower

than that for the Constant Emissions scenario in both time periods. There is an increase in the total annual energy production under each scenario between the two time periods, for a similar reason given in the first paragraph of this section. Electricity production increases by 33% for

the Carbon Tax scenario while the increase for the Constant Emissions scenario is the same (34%) as that reported in the first paragraph of this section.

Table 3-2: Total annual energy production under different technology options arising from Moderate Decline and Carbon Tax scenarios

Figure 3-2 shows water demand under the Constant Emissions and Carbon Tax scenarios for the two time periods considered (viz. 2030 and 2050). The figure shows a marked difference in

water requirements amongst the two scenarios in each time period. The water requirement for the Carbon Tax scenario is consistently lower than that for the Constant Emissions scenario. In addition, the demand for water decreases for each scenario (35% for the Carbon Tax) between

the two time periods. Once again, this is an encouraging result: declination in water usage within the energy sector.

Technology option 2030 2050


Carbon Tax

(MWh)


Carbon Tax

(MWh)

Existing Coal 269 768 580 269 768 580 120 029 520 120 029 520

New Coal 18 242 700 72 226 200 183 916 200 317 944 200

CCGT 15 549 000 12 439 200 27 988 200 27 988 200

OCGT / Gas Engines

6 727 680 6 937 920 10 722 240 12 719 520

Hydro Imports 17 528 760 20 800 795 17 528 760 20 800 795

Hydro Domestic 60 444 60 444 60 444 60 444

PS (incl Imports) 254 040 254 040 254 040 254 040

Nuclear 53 674 272 14 990 112 103 157 760 0

PV 16 603 529 13 867 430 42 486 000 42 010 157

CSP 13 528 944 1 229 904 33 207 408 0

Wind 11 458 080 4 231 080 27 646 560 12 824 640

Other 56 064 56 064 0 0

Total 423 452 093 416 861 769 566 997 132 554 631 516



Figure 3-2: Annual water requirement for energy production under Constant Emissions and Carbon Tax scenarios

Table 3-3 shows the technology options under Advanced Decline and Carbon Budget scenarios.

It is seen that the total annual energy production under the Carbon Budget is slightly lower than that for the Constant Emissions scenario in 2030, with a reversed trend in 2050. There is an increase in the total annual energy production under each scenario between the two time periods. Electricity production increases by 41% for the Carbon Tax scenario while the increase for the Advanced Decline scenario is the same (35%) as that reported in the first paragraph of this section.

Figure 3-3 shows water demand under the Advanced Decline and Carbon Budget scenarios for

the two time periods considered (viz., 2030 and 2050). A minor difference is observed in water requirements between the two scenarios in each time period. The water requirement for the Advanced Decline scenario is lower than that of the Carbon Budget scenario in both time

periods. In addition, the demand for water for each scenario decreases (32% decrease for the Carbon Budget) between the two time periods. From a water perspective, this shows that the

Advanced Decline scenario would be more preferred than the Carbon Budget.

Table 3-3: Total annual energy production under different technology options arising from Advanced Decline and Carbon Budget scenarios

0

1

2

3

4

5

6

7

8

2030 2050

Wa

ter

usa

ge

(x1

010

litr

e)

Year

Constant Emissions

Carbon Tax


Advanced Decline

(MWh)

Carbon Budget (MWh)

Advanced Decline

(MWh)

Carbon Budget

(MWh)

Existing Coal 269 768 580 273 268 200 120 029 520 120 029 520

New Coal 18 242 700 33 134 700 38 719 200 33 134 700

CCGT 15 549 000 18 658 800 37 317 600 21 768 600

OCGT / Gas Engines

6 727 680 7 148 160 9 986 400 9 671 040

Hydro Imports 17 528 760 19 164 777 17 528 760 19 164 777

Hydro Domestic 60 444 60 444 60 444 60 444

PS (inc. Imports) 254 040 254 040 254 040 254 040

Nuclear 53 674 272 27 884 832 232 104 960 257 894 400

PV 16 416 590 15 379 932 42 486 000 42 367 039

CSP 14 758 848 11 479 104 48 786 192 53 705 808

Wind 11 904 840 9 171 720 28 303 560 29 433 600

Other 56 064 56 064 0 0

Total 424 941 818 415 660 774 575 576 676 587 483 969



Figure 3-3: Annual water requirement for energy production under Advanced Decline and Carbon Budget scenarios

3.2 Technology-specific scenarios compared to Moderate Decline

DoE (2030) reports (in the IRP update report) a pairwise comparison of technology-specific

energy scenarios, which is useful in decision-making. A comparison of the associated water usage is presented in this section.

3.2.1 Rooftop PV scenario Table 3-4 shows the technology options under Moderate Decline and Rooftop PV scenarios. It can be seen that the total annual energy production under the Rooftop PV scenario is slightly

lower than that of the Moderate Decline scenario in 2030, with a reversed trend in 2050. There is an increase in the total annual energy production under each scenario between the two time periods, as expected.

Table 3-4: Total annual energy production under different technology options arising from Moderate Decline and Roof Top scenarios


Moderate Decline (MWh)

Rooftop PV (MWh)

Moderate Decline (MWh)

Rooftop PV

(MWh)

Existing Coal 269 768 580 269 768 580 120 029 520 12 0029 520

New Coal 18 242 700 18 242 700 94 564 200 100 148 700

CCGT 15 549 000 12 439 200 40 427 400 46 647 000

OCGT / Gas Engines 6 832 800 11 773 440 9 986 400 15 032 160

Hydro Imports 17 528 760 17 528 760 17 528 760 17 528 760

Hydro Domestic 60 444 60 444 60 444 60 444

PS (incl Imports) 254 040 254 040 254 040 254 040

Nuclear 53 674 272 27 884 832 167 631 360 141 841 920

PV 16 365 607 51 640 883 42 486 000 92 972 964

CSP 13 528 944 2 869 776 44 686 512 16 398 720

Wind 11 169 000 9 960 120 28 067 040 28 566 360

Other 56 064 56 064 0 0

Total 423 030 211 422 478 839 565 721 676 579 480 588

The water demand under the Moderate Decline and Rooftop scenarios is presented in Figure 3-4. The Rooftop PV scenario displays lower usage of water than the Moderate Decline, with a general decrease in water usage between the two time periods. It is interesting to note that the

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6

7

8

2030 2050

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(x

1012

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Advanced Decline

Carbon Budget



Rooftop scenario requires less water than the Moderate Decline Scenario. This expected because the water intensity for the PV technology is relatively low.

Figure 3-4: Annual water requirement for energy production under Moderate Decline and Rooftop PV scenarios

3.2.2 Big gas Table 3-5 demonstrates that the total annual energy production under the Moderate Decline is

higher than that of the Big Gas scenario in both time periods. Again, there is an increase in the total annual energy production under each scenario between the two time periods, ascribed to

population and industrial growth. In 2050, about 65% of the total annual electricity is produced by the CCGT technology under this scenario, which is quite significant.

Table 3-5: Total annual energy production under different technology options arising from the Moderate Decline and the Big Gas scenarios


Moderate Decline

(MWh)

Big Gas

(MWh)

Moderate Decline

(MWh)

Big Gas

(MWh)

Existing Coal 269 768 580 261 280 140 120 029 520 87 043 740

New Coal 18 242 700 8 935 200 94 564 200 8 935 200

CCGT 15 549 000 71 525 400 40 427 400 273 662 400

OCGT / Gas Engines 6 832 800 3 994 560 9 986 400 5 886 720

Hydro Imports 17 528 760 17 528 760 17 528 760 17 528 760

Hydro Domestic 60 444 60 444 60 444 60 444

PS (incl Imports) 254 040 254 040 254 040 254 040

Nuclear 53 674 272 14 990 112 167 631 360 0

PV 16 365 607 8 004 362 42 486 000 27 021 096

CSP 13 528 944 1 229 904 44 686 512 0

Wind 11 169 000 3 416 400 28 067 040 3 074 760

Other 56 064 56 064 0 0

Total 423 030 211 391 275 386 565 721 676 423 467 160

The result of replacing nuclear with shale gas is presented in Figure 3-5. It is observed that the Big Gas scenario is more water-efficient than the Moderate Decline scenario in both time

periods. In addition, the total annual water demand for generating electricity declines for both scenarios. This observation is attributed to the relatively lower water intensity for CCGT and OCGT/Gas engine energy technologies (DoE 2013). Increasing the share of gas allows more

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Moderate Decline

Rooftop PV



electricity to be produced by these technologies. It should be noted that fracking requires some water and contributes to contamination of water resources (Kharaka et al 2013). In addition, Wilson et al (2012) report that most of the water used in the production chain of gas-fired

thermoelectric power is during generation (for wet-cooled power plants). Based on the water intensities assumed in the IRP update, CCGT and OCGT/Gas engines have relatively lower demands for water than coal (DoE 2013). Consequently, increasing the share of gas would tend to reduce the total annual water demand.

Figure 3-5: Annual water requirement for energy production under Moderate Decline and Big Gas scenarios

3.2.3 Higher nuclear cost Table 3-6 provides an overview of how the various generating technologies reacted to the different prices in overnight cost of nuclear energy. The total annual energy production is higher

under the Higher Nuclear Cost scenario in both years. The IRP scenarios assumed an upfront investment cost of $5 800 / kW, whereas the higher nuclear cost assumed $7 000/ kW. In addition, there is an increase in energy production between the time periods.

Table 3-6: Total annual energy production under different technology options arising from a High Nuclear Cost scenario


Moderate Decline

(MWh)

Higher Nuclear Cost

(MWh)

Moderate Decline

(MWh)

Higher Nuclear Cost

(MWh)

Existing Coal 269 768 580 269 768 580 120 029 520 120 029 520

New Coal 18 242 700 21 965 700 94 564 200 88 979 700

CCGT 15 549 000 12 439 200 40 427 400 90 184 200

OCGT / Gas Engines 6 832 800 5 045 760 9 986 400 2 312 640

Hydro Imports 17 528 760 17 528 760 17 528 760 17 528 760

Hydro Domestic 60 444 60 444 60 444 60 444

PS (inc. Imports) 254 040 254 040 254 040 254 040

Nuclear 53 674 272 14 990 112 167 631 360 0

PV 16 365 607 17 453 249 42 486 000 42 486 000

CSP 13 528 944 54 935 712 44 686 512 156 197 808

Wind 11 169 000 19 578 600 28 067 040 66 435 840

Other 56 064 56 064 0 0

Total 423 030 211 434 076 221 565 721 676 584 468 952

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8

2030 2050

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(x1

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Moderate Decline

Big Gas



Figure 3-6 shows the total water demand for generating electricity with Higher Nuclear Cost. This figure demonstrates that the Higher Nuclear Cost scenario is slightly more water-efficient than the Moderate Decline scenario in 2030 and 2050. The Moderate Decline scenario exhibits a

reduction in water demand between the two time horizons, with a reversed trend for the Higher Nuclear Decline. This observation is probably due to the fact that increasing the cost of nuclear energy allows CSP, wind and CCGT gas to make up for the shortfall (DoE 2013). It should be noted that CSP technology, which has relatively high water intensity, contributes the largest proportion (about 27%) of the total annual electricity in 2050.

Figure 3-6: Total annual water withdrawal under the Moderate Decline and High Nuclear Cost scenarios

3.2.4 Higher Coal Cost The base case for this scenario uses R350 per ton for new coal-fired generation (DoE 2013). For the Higher Coal Cost scenario, R500 per ton is used for new coal-fired plants, but the price for existing coal remains at R150 per ton. The low price of coal will therefore have a direct impact on water demand. If coal remains the most affordable generating technology, a high demand for water will exist.

Table 3-7 presents the annual energy production under the Higher Coal Cost scenario. These

findings show that the total annual energy production is higher under the Higher Coal Cost in 2030, with a reversed trend in 2050. There is an increase in energy production for both scenarios between the time periods.

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8

9

2030 2050

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Moderate

Decline

Higher Nuclear

Cost



Table 3-7: Technology options arising from a high coal cost scenario


Moderate Decline

(MWh)

Higher Coal Cost

(MWh)

Moderate Decline

(MWh)

Higher Coal Cost

(MWh)

Existing Coal 269 768 580 269 768 580 120 029 520 120 029 520

New Coal 18 242 700 21 965 700 94 564 200 77 810 700

CCGT 15 549 000 12 439 200 40 427 400 55 976 400

OCGT / Gas Engines 6 832 800 6 832 800 9 986 400 11 563 200

Hydro Imports 17 528 760 17 528 760 17 528 760 17 528 760

Hydro Domestic 60 444 60 444 60 444 60 444

PS (inc. Imports) 254 040 254 040 254 040 254 040

Nuclear 53 674 272 53 674 272 167 631 360 154 736 640

PV 16 365 607 16 807 462 42 486 000 42 486 000

CSP 13 528 944 13 528 944 44 686 512 34 027 344

Wind 11 169 000 11 694 600 28 067 040 2 7304 920

Other 56 064 56 064 0 0

Total 423 030 211 424 610 866 565 721 676 541 777 968

Figure 3-7 shows the total water demand for generating electricity with Higher Coal Cost. It is observed that the total annual water demand for the two scenarios is comparable in 2030 but significantly different in 2050, with the Higher Coal Cost scenario being more favourable. This is attributed to the fact that increasing the cost of coal permits the gas technology, which has a low water intensity, to be competitive.

Figure 3-7: Total annual water withdrawal arising from the High Coal Cost scenario

Solar ParkTable 3-8 shows the total annual energy production under the Moderate Decline and Solar Park scenarios. More energy is produced under the Moderate Decline scenario than the

Solar Park scenario in 2030 and 2050. The total annual energy production is projected to increase under both scenarios between the two time periods, as expected.

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2

3

4

5

6

7

8

2030 2050

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Moderate Decline

Higher Coal Cost



Table 3-8: Total annual energy production under different technology options arising from a Solar Park test case


Moderate decline

(MWh)

Solar Park

(MWh)

Moderate decline

(MWh)

Solar Park

(MWh)

Existing Coal 269 768 580 269 768 580 120 029 520 120 029 520

New Coal 18 242 700 18 242 700 94 564 200 94 564 200

CCGT 15 549 000 12 439 200 40 427 400 40 427 400

OCGT / Gas Engines 6 832 800 6 517 440 9 986 400 10 932 480

Hydro Imports 17 528 760 17 528 760 17 528 760 17 528 760

Hydro Domestic 60 444 60 444 60 444 60 444

PS (incl imports) 254 040 254 040 254 040 254 040

Nuclear 53 674 272 40 779 552 167 631 360 167 631 360

PV 16 365 607 15 023 050 42 486 000 42 367 039

CSP 13 528 944 28 697 760 44 686 512 38 536 992

Wind 11 169 000 9329 400 28 067 040 27 751 680

Other 56 064 56 064 0 0

Total 423 030 211 418 696 990 565 721 676 560 083 915

The total water demand for generating electricity with Solar Park is provided in Figure 3-8. This figure demonstrates that the Moderate Decline scenario is more water-efficient than the Solar Park scenario in 2030, with a reversed trend in 2050. The total annual water demand declined for both scenario, with the Solar Park scenario being more preferred from a water perspective.

Figure 3-8: Total annual water consumption arising from the Solar Park scenario

3.3 Restrained learning rate In the Retrained Learning Rate, no learning was applied for nuclear, biomass, IGCC and wind energy technologies, with a more restrained learning for CSP (DoE 2013). Table 3-9 shows the annual energy production from various technology options under the Moderate and Restrained Learning Rates. There is a general increase in the energy production for both scenarios between the two time periods. In each year, the energy production levels are comparable between the two scenarios.

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8

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Moderate Decline

Solar Park



Table 3-9: Total annual energy production under different technology options arising from the Restrained Learning Rate scenario

Technology option

2030 2050

Moderate Decline

(MWh)

Restrained Learning Rate

(MWh)

Moderate Decline

(MWh)


(MWh)

Existing coal 269 768 580 269 768 580 120 029 520 120 029 520

New coal 18 242 700 21 965 700 94 564 200 94 564 200

CCGT 15 549 000 12 439 200 4 0427 400 55 976 400

OCGT / Gas Engines 6 832 800 6 096 960 9 986 400 8 094 240

Hydro imports 17 528 760 20 800 795 17 528 760 20 800 795

Hydro domestic 60 444 60 444 60 444 60 444

Pumped Storage 254 040 254 040 254 040 254 040

Nuclear 53 674 272 7 9463 712 167 631 360 244 999 680

PV 16 365 607 11 658 158 42 486 000 22 857 468

CSP 13 528 944 1 229 904 44 686 512 0

Wind 11 169 000 3 416 400 28 067 040 1 445 400

Other 56 064 56 064 0 0

Total capacity 423 030 211 427 209 958 565 721 676 569 082 187

The total water demand for generating electricity under the Restrained Learning Rate is provided in Figure 3-9. In both time horizons, total annual water demand for the Restrained Learning Rate is lower than that for the Moderate Decline scenario. The figure also shows that there is general decline in the water demand for both scenarios in spite of the general increase in energy production. Under the Restrained Learning Rate, there is no capacity for CSP and

nuclear and gas CCGT replace costly renewable energy technologies (DoE 2013). It is envisaged that nuclear energy would use sea water and the water intensity of CCGT (19.2 litre/MWh) reported in the IRP update is also relatively low. The result of this is a reduction in

the total amount of water required under this scenario.

Figure 3-9: Annual water requirement for energy production under Moderate Decline and Restrained Learning Rate scenarios

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2030 2050

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Moderate Decline




3.4 Inter-comparison of water requirements for scenarios

Renewable energy (RE) is one of the pillars for mitigating climate change. In this regard, the variation of the technology shares of RE in the projected energy mix of South Africa in 2030 and 2050 is given in (b)

Figure 3-10. Big Gas (BG) has the lowest share of renewable resource technologies in 2030, with the Restrained Learning Rate (LR) exhibiting the lowest share in 2050, which shows that that RE is not as competitive under these scenario in this time period. On the other hand, a Higher Nuclear Cost (HN) allows the largest proportion of energy production from the

renewable energy technologies (considered in this analysis) in both time periods, with a significant proportion generated by CSP. Wet-cooled CSP is water-intensive, and so it would tend to elevate the total water usage under this scenario.

(a)

(b)

Figure 3-10: Share of renewable energy in electricity generation in South Africa for: a) 2030, and b) 2050

Results also indicate an increase in the share of RE between the two time horizons for each scenario, except for the Restrained Learning Rate scenario Figure 3-11. It is pleasing to note

that all scenarios pertaining to climate change exhibit increasing shares of electricity generation from RE resources. This observation is encouraging, considering the fact that RE is one of the pillars of sustainable energy production.

0

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30

CE MD AD CT S5 PV BG HN HC SP LR

Technolo

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share

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E (

%)

Scenario

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30

40

50

60


Share

of R

E (

%)

Scenario



Figure 3-11: Share of renewable energy (RE) in electricity generation in South Africa for 2030 and 2050

A summary of the annual water requirements for all considered scenarios is provided in Figure 3-12. The Big Gas scenario (BG) exhibits the lowest demand for water while the High Nuclear Cost (HN) requires the highest amount of water in both time horizons. When the cost of nuclear energy is high, no new nuclear units are built and this shortfall in capacity is taken up by CSP, wind and CCGT gas (DoE 2013). It should be noted that the water intensity for wet-cooled CSP plants is relatively high. Consequently, an increase in the share of CSP would not effectively

reduce the water demand for energy production. From a water perspective, results indicate that the Big Gas scenario is most favourable. For gas, the largest proportion of the water is used in the generation stage (Wilson et al 2012).

(a)

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E (

%)

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2030

2050

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Wate

r usage (

x10

10

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)

Scenario



(b)

Figure 3-12: Annual water usage for energy production for all scenarios for the time periods: a) 2030 and b) 2050

One of the objectives the IRP is to reduce water consumption in the energy sector (DoE 2013).

It can be observed from Figure 3-13 that the demand for water decreases (except for the Higher Nuclear Cost, HN) between the two time horizons, in spite of the increasing electricity production. This is probably due to the rise in the shares of electricity generation by using energy technologies (such as solar PV and wind) with low water intensities. The Higher Nuclear Cost allows more energy to be produced from renewables. It should be noted, however, that increasing the share of wet-cooled CSP in the generation of electricity augments water usage in energy sector.

Figure 3-13: Annual water usage for energy production for all scenarios in 2030 and 2050

4. Concluding remarks Water usage in the generation of electricity under eleven different scenarios for South Africa, has been investigated using data from the IRP update (D0E 2013). Eleven energy scenarios

were analysed: Constant Emissions, Moderate Decline, Advanced Decline, Carbon Tax, Carbon Budget, Rooftop PV, Big Gas, Higher Nuclear Cost, Higher Coal Cost, Solar Park and

Restrained Learning Rate. Two time periods were established (2030 and 2050) by using the existing national data on energy scenarios. These data were used to calculate the annual volume of water under each scenario.

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x10

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re)

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2050



Results show that there is a general increase in electricity generation between the two time horizons. The share of renewables in the generation of electricity, for each scenario, also rises between 2030 and 2050. In addition, the Big Gas scenario exhibited the lowest demand for

water in both 2030 and 2050 time horizons. A higher share of renewable energy, especially solar PV and wind, can assist in bringing down the demand for water in the energy mix.

With regard to further work: In the next phase of the WRC project, the trade-offs between resource choices within South Africa will be analysed in order to give a clearer picture of the balance between the need to increase renewable energy and the need to ensure a supply of water for energy generation in the context of water scarcity and climate change.



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Appendix: Data on capacity of technology options under different scenarios considered in this investigation

Table A1: Technology options arising from the Carbon Budget scenario relative to the Advance Decline Source: IRP (2013)

Technology option Constant Emissions

2030

MW

Moderate Decline

2050

MW

Advanced Decline

2030

MW

Constant Emissions

2050

MW

Moderate Decline

2030

MW

Advanced Decline

2050

MW

Existing coal 36 230 36 230 36 230 16 120 16 120 16 120

New coal 2 450 2 450 2 450 24 700 12 700 5 200

CCGT 3 550 3 550 3 550 6 390 9 230 8 520

OCGT / Gas Engines 7 680 7 800 7 680 12 240 11 400 11 400

Hydro imports 3 000 3 000 3 000 3 000 3 000 3 000

Hydro domestic 690 690 690 690 690 690

Pumped Storage 2 900 2 900 2 900 2 900 2 900 2 900

Nuclear 6 660 6 660 6 660 12 800 20 800 28 800

PV 9 770 9 630 9 660 25 000 25 000 25 000

CSP 3 300 3 300 3 600 8 100 10 900 11 900

Wind 4 360 4 250 4 530 10 520 10 680 10 770

Other 640 640 640 0 0 0

Total capacity 81 230 81 100 81 590 122 460 123 420 124 300

Table A2: Technology options arising from the Rooftop PV scenario Source: IRP (2013)

Technology option Moderate decline 2030

(MW)

Rooftop PV 2030

(MW)

Moderate decline 2050 (MW)

Rooftop PV 2050

(MW)

Existing Coal 36 230 36 230 16 120 16 120

New Coal 2 450 2 450 12 700 13 450

CCGT 3 550 2 840 9 230 10 650

OCGT/Gas Engines 7 800 13 440 11 400 17 160

Hydro Imports 3 000 3 000 3 000 3 000

Hydro Domestic 690 690 690 690

PS (incl Imports) 2 900 2 900 2 900 2 900

Nuclear 6 660 3 460 20 800 17 600

PV - 21 617 - 29 778

Additional PV 9 630 8 770 25 000 24 930

CSP 3 300 700 10 900 4 000

Wind 4 250 3 790 10 680 10 870

Other 640 640 - -

Total 81 100 100 527 123 420 151 148



Table A3: Technology options arising from the Big Gas scenario Source: IRP (2013)

Technology option Moderate decline 2030 (MW)

Big Gas 2030

(MW)

Moderate decline 2050

(MW)

Big Gas 2050

(MW)

Existing Coal 36 230 36 230 16 120 16 120

New Coal 2 450 2 450 12 700 13 450

CCGT 3 550 2 840 9 230 10 650

OCGT / Gas Engines 7 800 13 440 11 400 17 160

Hydro Imports 3 000 3 000 3 000 3 000


PS (incl Imports) 2 900 2 900 2 900 2 900

Nuclear 6 660 3 460 20 800 17 600

PV 0 21 617 0 29 778

Additional PV 9 630 8 770 25 000 24 930

CSP 3 300 700 10 900 4 000

Wind 4 250 3 790 10 680 10 870

Other 640 640 - -

Total 81 100 100 527 123 420 151 148

Table A4: Technology options arising from a High Nuclear Cost scenario Source: IRP (2013)


(MW)

High nuclear costs 2030

(MW)


(MW)

High nuclear costs 2050

(MW)

Existing Coal 36 230 36 230 16 120 16 120

New Coal 2 450 2 950 12 700 11 950

CCGT 3 550 2 840 9 230 20 590

OCGT / Gas Engines 7 800 5 760 11 400 2 640

Hydro Imports 3 000 3 000 3 000 3 000


PS (incl Imports) 2 900 2 900 2 900 2 900

Nuclear 6 660 1 860 20 800 0

PV 9 630 10 270 25 000 25 000

CSP 3 300 13 400 10 900 38 100

Wind 4 250 7 450 10 680 25 280

Other 640 640 0 0

Total 81 100 87 990 123 420 146 270



Table A5: Technology options arising from a High Coal Cost scenario Source: IRP (2013)


(MW)

High coal costs 2030

(MW)

Moderate decline2050

(MW)

High coal costs 2050

(MW)

Existing Coal 36 230 36 230 16 120 16 120

New Coal 2 450 2 950 12 700 10 450

CCGT 3 550 2 840 9 230 12 780

OCGT / Gas Engines 7 800 7 800 11 400 13 200

Hydro Imports 3 000 3 000 3 000 3 000


PS (incl Imports) 2 900 2 900 2 900 2 900

Nuclear 6 660 6 660 20 800 19 200

PV 9 630 9 890 25 000 25 000

CSP 3 300 3 300 10 900 8 300

Wind 4 250 4 450 10 680 10 390

Other 640 640 0 0

Total 81 100 81 350 123 420 122 030

Table A6: Technology options arising from a Solar Park test case Source: IRP (2013)


(MW)

Solar Park 2030

(MW)


(MW)

Solar Park 2050

(MW)

Existing Coal 36 230 36 230 16 120 16 120

New Coal 2 450 2 450 12 700 12 700

CCGT 3 550 2 840 9 230 9 230

OCGT / Gas Engines 7 800 7 440 11 400 12 480

Hydro Imports 3 000 3 000 3 000 3 000


PS (incl Imports) 2 900 2 900 2 900 2 900

Nuclear 6 660 5 060 20 800 20 800

PV 9 630 8 840 25 000 24 930

CSP 3 300 7 000 10 900 9 400

Wind 4 250 3 550 10 680 10 560

Other 640 640 0 0

Total 81 100 80 640 123 420 122 810



Table A7: Technology options arising from the Restrained Learning Rate scenario Source: IRP (2013)

Technology option


MW

Restrained learning

2030

MW


MW

Restrained learning

2050

MW

Existing coal 36 230 36 230 16 120 16 120

New coal 2 450 2 950 12 700 12 700

CCGT 3 550 2 840 9 230 12 780

OCGT / Gas Engines 7 800 6 960 11 400 9 240

Hydro imports 3 000 3 560 3 000 3 560

Hydro domestic 690 690 690 690

Pumped Storage 2 900 2 900 2 900 2 900

Nuclear 6 660 9 860 20 800 30 400

PV 9 630 6 860 25 000 13 450

CSP 3 300 300 10 900 0

Wind 4 250 1 300 10 680 550

Other 640 640 0 0

Total capacity 81 100 75 090 123 420 102 390

Documents

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