Tuesday, May 24, 2011

Solar and invasive bush-burning could power southern Africa

Three articles show potential for clean energy in Southern Africa.



Greater emphasis should be given to solar in future SA power mix

By: Martin Zhuwakinyu
20th May 2011

A senior executive at engineering group Siemens� Israel-based
Concentrated Solar Power subsidiary has said South Africa would
derive greater benefit if it placed more emphasis on concentrating
solar power (CSP) as a component of its future energy mix.

The latest version of the country�s Integrated Resource Plan (IRP),
published in April, envisages CSP accounting for 1 000 MW of South
Africa�s total energy generation by 2030, compared with 8 400 MW each
for wind and solar photovotaic (PV).

The first 300 MW of new solar PV is expected to be available in 2012,
while the currently uncommitted 400 MW of wind energy is set down for
2014. CSP capacity is to be introduced only from 2016.

Siemens Concentrated Solar Power business development director Ilan
Sharon told Engineering News in Tel Aviv, Israel, early this month,
that he believed South Africa would derive greater benefit if it
allocated a bigger chunk to CSP than the 1 000 MW set aside in the IRP
� a far cry from the allocations for wind and solar PV.

�I think allocating a greater capacity to wind and solar PV is a big
mistake that South Africa has made,� he said, explaining that PV-based
solar power plants and wind farms needed backup each time there was
cloud cover or the wind stopped blowing, which was not the case with

He said CSP technology provided for greater grid stability, as
generation hours could be extended by storing the heat that is
produced and releasing it when required.

While storage of the heat generated by CSP technology could not
guarantee uninterrupted electricity production, Sharon said
�hybridisation� between a solar farm and a backup plant fired by gas
or coal would be the solution for �24/7 power generation�.

The Siemens group supplies CSP systems and other solar technologies,
but Sharon was at pains to explain this was not the reason he would
have preferred to see a bigger allocation for CSP in the latest
version of the IRP.

CSP, he said, was a proven technology that had been used at utility
scale for decades. In the Mojave desert, in California, US, nine solar
thermal plants with a combined capacity of 352 MW had been supplying
sustainable power to the grid for more than 20 years, and plants with
a combined capacity of 3 500 MW were about to be commissioned in Spain.

Sharon said that large-scale deployment of CSP plants in South Africa,
a country endowed with high levels of irradiation, could lead to the
establishment of local support industries, thereby creating thousands
of jobs.

�The amount of local content, which will require investment, will
depend on the capacity to be installed and the degree of certainty
regarding long-term market growth.

�Securing the future of the CSP industry in South Africa [equates to]
investing in the future of the people of South Africa. Each technology
has its pros and cons, and I think the current renewable-energy mix
must be revised.�

Sharon also noted that South Africa�s renewable-energy feed-in tariff
should be high enough to �ignite� the CSP market in South Africa.

Edited by: Martin Zhuwakinyu


Construction on solar power demonstration plant to start in 2013

By: Tracy Hancock
13th May 2011

State-owned power utility Eskom intends to start construction of a 100
MW central-receiver system concentrating solar power demonstration
plant, near Upington, in the Northern Cape, in 2013. The proposed
project is currently the largest of its kind in the world.

�The 4 km2 plant, comprising between 4 000 and 5 000 heliostat
mirrors, will involve the use of thermal storage to ensure a readily
avail- able power supply to offset morning and evening peak capacity
demands,� explains Eskom divisional executive for corporate services
Dr Steve Lennon.

The plant is scheduled to be fully operational by 2015; however,
Lennon would like to see this deadline moved forward.

Eskom has secured the environmental approvals as well as land and
water for the project and is currently in the process of appointing an
owner�s engineer, the repre- sentative of the commissioning company.
The initial indication of the project�s cost is between R6-billion and
R7-billion; however, as this is a demonstration project, there is a
lot of uncertainty surrounding the costs. The true cost of the project
will only be known once the commercial bids have been finalised, says

Eskom also intends to develop a full-scale 1 GW solar plant, near
Upington, in parallel with the development of the demonstration plant.

The aim of the commercial plant is to produce electricity at a cost
competitive with that of wind power generation, which is currently
priced at about R1,20/kWh.

�This is incredibly ambitious as solar is priced at about R3/kWh.
However, as the technology evolves, this cost should reduce signifi-
cantly to become competitive with coal and nuclear power generation,�
says Lennon.

The 1 GW commercial plant may potentially form part of the Department
of Energy�s proposed 5 GW solar park, which has an estimated cost of
more than R20-billion. This project is in partnership with the Clinton
Climate Initiative, an organisation headed by former US President Bill
Clinton, and is currently under- going a feasibility study.

�The Northern Cape has more than enough solar energy potential to
support a project of this size, as it is one of the best solar
resources in the world. However, issues that need to be considered are
the availability of water, which solar plants require for cooling and
washing, and transmission interconnection capacity. The implementation
of a 5 GW project, in the central region of South Africa, will require
significant transmission investment,� says Lennon.

He also notes that, should Eskom fund 1 GW of the proposed 5 GW
project, the remaining 4 GW presents a significant opportunity for
independent power producers (IPPs).

Wind Power Generation

Eskom�s 100 MW Sere wind farm on the west coast, near Koekenaap, is in
the procurement phase and is on track to meet its 2013 deadline, says
Lennon, who adds that Eskom may be able to bring the completion date
of the project forward by a year.

This project currently has an approved project cost of R3,4-billion,
which is subject to change.

Simultaneously, the utility is conducting a feasibility study for a
500 MW wind farm, earmarked for the Southern or Western Cape.

Lennon says it is difficult to determine South Africa�s potential wind
energy capacity, as that depends on the number of commercially viable
wind farms in operation, while wind turbine technology is constantly
improving to operate more efficiently at low and high wind speeds.

Green Division
Eskom�s renewables business unit, which was set up to increase the
utility�s renewables footprint and reduce its carbon dioxide (CO2)
emissions, came into operation on April 1.

Since 2007, the utility has aimed to reduce its relative CO2 emissions
for every unit of electricity produced up to 2025, there- after
concentrating on its absolute emissions. Currently, Eskom produces
0,98 kg of CO2/kWh.

To reduce the carbon emissions emitted by its coal-fired power
stations, the utility is concentrating on improving the efficiency
levels at which the stations burn coal.

Further, the utility is investigating biomass cofiring to reduce its
carbon emissions by 10% at each of its coal-fired power stations. This
involves blending biomass with coal, and a feasibility study is at an
advanced stage.

Eskom is also investigating solar augmentation, which involves
preheating water for boiler use, using solar concentrators, as well as
the use of photovoltaic (PV) solar modules to offset the power
requirements of each unit at its coal-fired power stations by 20 MW.

To further reduce its carbon emissions, the utility also intends to
increase the number of renewables projects in its portfolio and
execute nuclear build projects, which are dependant on government�s
directive under the second Integrated Resources Plan.

Over the past five years, the utility has also been investigating
marine current energy extraction, particularly from the Agulhas
current, which is the western boundary current of the south-west
Indian Ocean and flows along the East Coast of Africa.

�The concept involves the instal- lation of turbines on the seabed to
harness the energy produced by the current. This technology has been
piloted by other countries and is currently being evaluated by Eskom,�
explains Lennon.

He says South Africa has limi- ted hydro potential, with most of the
country�s hydro potential exploited by a 360 MW hydroelectric power
station at the Gariep dam. Eskom is considering smaller projects;
however, these projects may be better suited to IPPs, notes Lennon.

This year, the utility also intends to implement a solar project in
the parking lot of its Megawatt Park head office, which involves the
use of PV panels as carport roofing.

The project will be used to offset the electricity demand at Megawatt
Park and will incorporate an electric vehicle (EV) charging station.
Eskom has received interest from various EV manufacturers and is
willing to work with them to develop EV charging standards. The
utility also expects a proposal from vehicle manufacturer Nissan soon.

�Eskom will encourage the use of EVs and is exploring the use of EVs
in its vehicle fleet. The implementation of this will depend on the
pace of commercial roll-out of EVs in South Africa,� says Lennon.

Renewables History

Before the implementation of the renewables business unit, renewables
projects were being run by Eskom�s research and development and
generation divisions.

Currently, the operating costs of the renewables business unit is
pegged at between R50-million and R100-million a year. The capital
costs of renewables projects will be determined by whether Eskom
provides full funding or funds the projects through partnerships.

Eskom started investigating large-scale renewables projects in about
2000 and by 2002 was operating a 3,6 MW Klipheuwel wind demonstration
farm, worth R20-million, and a R5-million solar unit at development
finance institution Development Bank of Southern Africa, while also
developing large-scale PV solar projects.

�Since 2007, we have prob- ably spent between R100-million and R200-
million on renew- ables projects, with the majority of these funds
allocated to project development involving wind and solar power
generation,� says Lennon.

However, in 2007, funding constraints put the development of
renewables projects identified by Eskom on hold. Funding for these
projects was included in the utility�s application for its $3,7-
billion loan from the World Bank, which was secured in April 2010.

Edited by: Chanel de Bruyn
NamPower moves to study Namibia�s bush-to-power potential

By: Terence Creamer
23rd May 2011

Namibia�s national power utility NamPower plans to conduct a
prefeasibility study into the potential for biomass power plants,
fuelled using wood from invasive bush, which is said to be
accelerating desertification and undermining agriculture in the vast
Southern African country.

The utility has issued a tender notice calling on experienced
organisations and individuals to prequalify for the study, which is
expected to provide a �roadmap� for developing such power facilities.

Scientific reports have highlighted the threat associated with the
�encroacher bush�, which is reportedly making large areas of the
country�s land unusable for rural farmers and shrinking the overall
arable agricultural land resource.

A 2010 report by Combating Bush Encroachment for Namibia's
Development, or C-Bend, notes that 26-million hectares have already
been affected.

One mitigation project being suggested be C-Bend and the Desert
Research Foundation of Namibia is to convert invading bush into
energy, using wood-gasification plants.

The NamPower prefeasibility study will seek to analyse the potential
for such biomass power facilities, as well as identify possible sites
and technological solutions.

NamPower is currently supporting a C-Bend-backed �bush-to-electricity�
pilot plant in northern Namibia, through a power purchase agreement.

However, the promoters of the concept believe there is potential for
as many as 20 such wood-gasification plants.

The closing date for the tender is June 10, 2011.

Edited by: Creamer Media Reporter

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