1 1 The Utilisation of Renewable Energy Sources to Address the Security of Supply Challenges in SA...
-
Upload
erik-fisher -
Category
Documents
-
view
213 -
download
0
Transcript of 1 1 The Utilisation of Renewable Energy Sources to Address the Security of Supply Challenges in SA...
11
The Utilisation of Renewable Energy Sources to Address the Security of Supply Challenges in SA
Vally Padayachee
MBA; M.Sc (Eng); EDP (Wits)
Director (Operations)
AMEU CONVENTION 2007
October 2007
2
Presentation Outline
Scene setter questions
Background – security of supply
RE characteristics
RE sources – relative merits
Power generation mix
Govt stance
Challenges to RE roll-out
Distributor (munic) perspective
Recommendations
Conclusion
3
Scene setter questions
Is the present South African environment conducive to implementing
renewable energy systems?
Are they reliable? How do they impact on the current ‘generation mix’?
How much and what type is needed to effect supply security?
Some funding is available, but who and how will it be paid back?
Can the renewable energy challenges be overcome?
Are there any other ‘spin-offs’ other than environmental and supply
security benefits? Example, job creation and local manufacture
4
Security of supply
Cost – A ‘best investment / least cost’ approach to ensure the security of supply
The alternative - Load shedding – causes massive economic disruption
Present load shedding conditions are expected to persist for a five year period
Consider the relative cost of outages in economic terms -
In the residential sector the loss is the least, say equal to x
Relative loss to commercial and light industry sector can grow to 10 x
Loss to heavy industry can be upwards of 50 x
Mitigating economic risk from load shedding as distributors -
Characterize MV feeders by their loads and discriminate in favor of commerce and industry when shedding
5
Renewable Energy Characteristics
Chief criticism of renewable energy is the problem of intermittency -
Viewed as an unreliable source due to dependency on weather and climatic variations
Characteristics are not conducive to base nor peaking load applications
Uncertainty with regard to contribution to security of supply
Intermittency risks can be mitigated by -
Choosing complementary, diverse mixes of renewable sources
Geographical diversification – avoid localised weather conditions
6
Renewable Sources – Relative Merits (1)
Source Technology Intermittency Advantages Disadvantages Rating / 5Solar Thermal
Collectors (Water Heating)
Days Energy has no T&D loss.Energy storage component is built in
4
Solar Roof-top Photovoltaics
30 minutes No T&D losses Requires electronics to convert, batteries for storage
3
Solar Grid connected solar farms
Hours Desert locations, remote. Usually requires supplement from gas fired boilers 2
Wind Mechanical turbines
30 minutes Usually remotely located
2
Small Hydro Mechanical Turbines
Years With storage, suited to peak applications
Subject to droughts, limited opportunities
1
7
Renewable Sources – Relative Merits (2)
Source Technology Intermittency Advantages Disadvantages Rating / 5
Geo-thermal Ground source heat pumps
Grid co- dependent
Reduces T&D losses
Still requires electrical input, high maintenance – new technology 0,5
Biomass Landfill gas capture
Years – occasional relocation
In greenhouse gas terms, methane is 29 x CO2 value
Small scale, but reliable load factor.
1
Biomass Wood fuel A year Harvest and Transport logistics decrease energy yield.Subject to drought
1
Oceanic Wave energy convertors, tidal or ocean current turbines
Unknown Has potential to be non-intermittent
Industry is fledgling, development is needed
0,5
8
The Power Generation Mix (1)
Ideal generation mix (Reference SADELEC)
base load 72%
Mid-merit 13%
Peak generation 15%
South Africa presently has a >93% predominance of base load genearation
Where do renewable sources fit into the mix, and what are they really competing against ?
OCGT complementary relationship to solar thermal and wind intermittency
9
The Power Generation Mix (2)
Active DSM and intermittency (dynamic response) may also complement each
other
Renewable sources bring extra weather sensitivity risks to generation forecasting
and scheduling
Two views can be taken –
Renewable energy conflicts with peaking plant capacity requirements – the more renewable energy is employed, the more peaking plant will be required for shortfalls
Renewable energy complements peaking plant by reducing premium cost fuel consumption
10
Government Stance
Renewable Energy White Paper of 2003 –
Target of 10 000 GWh renewable energy contribution by 2013 (approx = 1667 MW)
Expectation is from wind, solar, biomass and small scale hydro
Utilization of renewable energy is therefore a ‘given’ and is driven by -
Climate change / environmental issues – CO2 reductions
Fossil fuel conservation
The long term need to diversify energy sources – too much dependency on a single fuel source (e.g. coal) is a risk in itself
A lot more is needed to make a reasonable impact
11
Challenges to Renewable Energy Roll out
Funding sources and easily accessed financing mechanisms need to be put in place for
home owners
Introduction of feed-in tariffs for utility scale renewable projects
Relative capital costs of renewable energy are high
Legislation to ensure the uptake of energy whenever it is available
Customer awareness and education
The current cheap, ‘dirty’ energy creates a barrier for the introduction of renewable energy
Competent manpower resources – accelerated training is needed
12
South African Wind Resources
Potential in the Western Cape is good
In progress - Darling Wind Farm 4 x 1,3
MW units - total 5.2 MW, on line
November 07
Eskom 100MW wind farm tender
Where else in South Africa is wind
potential good to realize geographical
diversity?
13
Eskom SWH Incentive
Eskom DSM will provide a monetary incentive
to assist the implementation of residential
Solar Water Heating Systems.
The SABS are equipped with the most modern outdoor test rig to measure the performance
The SABS also ensures that systems comply to national standards
Targets:
900 000 installations nationwide
R 2 billion provision made over the next 5 years
GLCincentive ffQRR 500
With Q the system rating determined by SABS for a standard
day in kWh;
fLC a modifier for Local Content that can increase or reduce the
incentive by up to 5%;
fG a modifier for Guarantee that can increase the incentive by up to
20%.
14
0
500
1000
1500
2000
2500
20
06
/08
/30
20
06
/09
/13
20
06
/09
/27
20
06
/10
/11
20
06
/10
/25
20
06
/11
/08
20
06
/11
/22
20
06
/12
/06
20
06
/12
/20
20
07
/01
/03
20
07
/01
/17
20
07
/01
/31
20
07
/02
/14
20
07
/02
/28
20
07
/03
/14
20
07
/03
/28
20
07
/04
/11
20
07
/04
/25
20
07
/05
/09
20
07
/05
/23
20
07
/06
/06
20
07
/06
/20
20
07
/07
/04
20
07
/07
/18
20
07
/08
/01
20
07
/08
/15
-
Solar
Electrical
Electrical / Solar
kW
h
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
Aug-06 Sep-06 Oct-06 Nov-06 Dec-06 Jan-07 Feb-07 Mar-07 Apr-07 May-07 Jun-07 Jul-07
-
Solar
Electrical
Electrical / Solar
kW
h
WEEKLY
MONTHLY
Selected Cut-Off
11694 - 56%
9301 - 44% 27634 - 48%
29978 - 52%
Electrical / Solar Electrical / Solar
Electrical Solar Electrical Solar
Before Timer Switch-On After Timer Switch-On
*Courtesy of SESSA and Eskom
Supplementary energy requirement is
seasonal
SWH - Actual measured performance
Control of supplementary energy
is essential
15
Distributor (Munic) Perspective – Solar Water Heating Systems
Winter security of supply risk – less frequent maybe, but still a threat -
56 overcast days per annum in South Africa – intermittency issue
Electricity industry to provide supplementary energy on low solar days
This may not avoid costs to re-enforcement networks in order to cope with bad solar days
Financial issues
Significant summer domestic revenue loss (max solar energy utilisation)
Without proper control of timing of electrical water heating energy, the risk of winter loss-making sales prevails. (Buy on Megaflex, but sell at flat rate)
Electricity networks still need to be maintained with less funds
16
Solar Water Heating – 3 Metros Proposed Initiative(Johannesburg, Tshwane and Ekhuruleni)
ESCO
Bulk Finance
SWH suppliers and installers
Install SWH
Medium-term loans $
$
Agreement
$
Repayments
$
Long- term loan
Carbon $
Eskom incentive
City Role
Endorse Facilitate financial agreements?
Grant “operating” license? (fee?)
Quality control?
(logo/branding)
Help desk?
E+Co loan guarantee
$
$
Domestic Energy Consumers
17
Distributor (Munic) Involvement as SWH ‘Energy Service Company’
Why get involved?
Offset summer revenue loss – perhaps provide maintenance services (“fee for service approach)
Collective and auditable carbon trading
Sustainability – Apply mass SWH rollout as if purchasing power station plant.
Metro distributors are the nuclei of future REDS
Metro’s expectations - full support to be given to Solar Water Heater systems implementation – key
stakeholder
‘Green City’ objective of shareholder
Summertime load relief - Don’t overlook – provides additional room to maneuver and apply band-aid to
power stations and distribution networks
18
Distributor (Munic) Strategy – Solar Water Heaters
Mitigate the ‘bad solar day’ demand risk by influencing system specifications –
Limit electrical element size to not more than 1,5 kW
Highest economically viable tank thermal insulation - < 1kWh per day
Increase nominal tank storage capacity by 50% over traditional electric geyser sizing
Use Load Management systems to support solar Water Heating systems
Create special SWH load group, tailored to weather conditions when necessary
Maximize shift of supplementary energy requirement to off-peak periods – does the work of the timer
19
Recommendations of the Way Forward
Stronger legislative support and enabling tariff structures
Customer and stakeholder education
Consider diversity of renewable resources
Also identify east coast wind sites
Also research oceanic (wave, tidal and current) sources to improve the mix
Spin-off benefits
New industries
Potential for job creation (EPWP, local manufacture,etc)
20
Conclusion
The RE landscape in SA – is it sufficient to mitigate adequacy and security of supply risks?
Consider also in the context of
Eskom Stage 1 load shedding = 1500 MW
Eskom Stage 2 load shedding= 3000 MW (average for last week)
Eskom Stage 3 load shedding = 4500 MW (are we going to reach this stage rather sooner than later)
At this stage ,
The answer could be ‘no’, up until 2012
Impact of ASGISA’s 6% GDP Growth (9% in Johannesburg) – if realised, has to be underpinned by adequate and secure energy (esp power) supplies
Conversely – in order to respond to environmental pressures – when would be a good time to start with renewable energy sources?
21
THANK YOU