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					Pin Chen Goh

1. PUB – Singapore’s National Water Agency

PUB, the national water agency, plans, manages and safeguards Singapore’s water
resources. Our mission is to secure an efficient, adequate and sustainable supply of
water. From rainwater collection to used water treatment, the entire water loop is
managed by PUB. By closing the water loop, PUB has put in place the 4 National Taps.
They are our 3 local sources (local catchments, NEWater and desalination.) and
imported water from Johor.

2. What PUB does

As the national water agency, PUB is responsible for the collection, production,
distribution and reclamation of water in Singapore.

                             Our Water Loop
                                                  to sea

3.      Pressing Challenges/Concerns in the water energy nexus

1.      How can we ensure a sustainable water supply?
2.      Alternative sources of water such as seawater desalination have a high energy
        footprint. Can we further reduce the energy footprint of such water sources?
3.      To what extent should Rainwater harvesting be encouraged?
4.      How can we better tap alternative sources of energy to further reduce the energy

4.      What PUB has done

Ensure a sustainable water supply

i.      Developing a robust water supply

        Through an integrated management of the water loop, PUB has developed a
unique Four National Taps strategy that not only ensures a diversified and robust supply,
but also sustainable for future generations.

     The four National Taps are:

     A. Water from local catchment – We are expanding our water catchment areas to
        turn two-thirds of Singapore’s total land area into catchment areas by 2010.

     B. Imported water - Singapore also imports water from Malaysia

     C. NEWater is high grade water reclaimed from treated effluent. It is extensively
        used in industries that need high grade water, particularly the wafer-fabrication
        industries. This will free up more drinking water to meet present and future
        demand from households and industries. In addition, a small amount of NEWater
         is being pumped to our reservoirs as a source of drinking water. By 2011, NW
         capacity is expected to cater to 30% of Singapore’s water demand.

      D. Desalination - In September 2005, Singapore turned on its fourth National Tap,
         with the opening of the SingSpring Desalination Plant in Tuas. This plant can
         produce 30 million gallons of water a day (136, 000 cubic meters) and is one of
         the region’s largest seawater reverse-osmosis plants. Desalinated water is
         blended with treated water before it is supplied to homes and industries in the
         western part of Singapore.

ii.      Managing Demand

Securing an adequate supply is only half of the water equation – managing the demand
side is just as crucial. PUB has a wide-ranging water conservation plan that encourages
customers to use water wisely. Singapore’s per capita domestic water consumption has
been brought down from 165 litres per day in 2003 to the current 157 litres. The target is
to lower it to 155 litres by 2012

Some examples of the programmes are

      a. The 10-Litre Challenge aims to get every individual to reduce daily water
         consumption by 10 litres. This programme encourages people to assess their
         individual water usage, learn the various water conservation measures and
         devices to achieve a saving of 10 litres per person per day

      b. Water Efficient Homes (WEH) is a programme to help residents save water at
         home and cut down on their water bills. The programme encourages residents to
         install water saving devices and practice good water conservation habits. As part
         of the programme, PUB officers visit households in Singapore to install free-of-
         charge water saving devices such as thimbles and cistern water saving bags.

      c. Water Volunteer Programme - PUB is actively working with the community to
         form Water Volunteer Groups (WVGs). The WVGs encourage residents to cut
         down on their water consumption by taking the 10-litre challenge.
   d. Water Efficiency Labelling Scheme – this involves labelling of appliances to so
       that consumers can make informed decisions when choosing their appliances
       and encourage buying of water efficient ones

Alternative sources of water such as Desalination have a high energy footprint;
can we further reduce the energy footprint of such water sources?

One area of interest is how we can continue to improve efficiency technologies such as
RO to further reduce the existing energy footprint.

Some examples of projects currently undertaken by PUB:

a) Membrane Bioreactor (MBR) - In MBR systems, membrane separation is combined
   with biological treatment. The membrane will acts a filter to remove all suspended
   solids from the water and therefore eliminates the need for final sedimentation tanks
   for removal of suspended solids from the effluent water.

b) Variable Salinity Plant - The Variable Salinity Plant (VSP) concept, utilizes
   membrane technology to produce potable water from feed source that ranges
   between fresh water with salinity less than 200 parts per million and sea water with
   salinity at 36,000 parts per million. The plant is designed as a seawater desalination
   plant but incorporates the flexibility to automatically switch to treatment of freshwater
   when freshwater feed is available.

c) Membrane Distillation (MD) is an advanced membrane based desalination process
   that makes use of temperature and vapour pressure difference to drive vapour
   through the membrane and condense it as distilled water

d) Capacitive Deionization (CDI) technology for the treatment and recovery of RO
   brine - Capacitive Deionization (CDI) technology is a non-membrane electrosorption
   process for continuous removal of ionic impurities in water. This technology is being
   used as the core of the brine treatment process for the recovery of water from the
   reverse osmosis (RO) brine from the NEWater factories. This R&D project is a joint
      collaboration amongst PUB, NUS and the European Union (EU) “RECLAIM”

    3. To what extent should Rainwater harvesting be encouraged?

Developers can build rainwater collection systems and underground tanks to collect
rainwater in their premises for their own non-potable uses, such as washing and toilet
flushing. This applies to premises located within water catchments as well as those
outside water catchments.

Our concern however is that unlike centralized systems such systems would have
limited storage and is likely to be less efficient when compared to a centralized system
(already about 2/3 of Singapore area are water catchments).

4. How can we better tap alternative sources of energy to further reduce the
energy footprint?

We are currently looking into how we use our facilities (installations, reservoirs, etc) to
tap solar energy.

  PUB is a member in the EU project RECLAIM Water. The RECLAIM Water project is a large-
scale research collaboration funded by the European Commission (EC) and comprises 20
international research organizations. PUB and NUS were invited to participate in the project on
the topic: "Treatment and Recovery of RO Brine from Water Reclamation Factories" as Targeted
Third Countries (TTC) partners outside EU. Our proposal has been accepted by EC. Project cost
for PUB-NUS is S$699,000, of which EC will contribute about S$396,000 and the remaining will
be funded by PUB.
  Itay Fischhendler: Integrating energy into IWRM: is it possible and desirable?

The implications of a fragmented water sector – or one that lacks coordination among
different resources or users – have often been used to justify the need for the adoption of
Integrated Water Resource Management – IWRM. IWRM seeks to create a process that
can bring together fragmented water uses and users into an integrated planning,
allocation and management framework, typically at the scale of a watershed.

Energy, is not different: the interconnectedness between different energy sources; the
establishment of a European energy market and a transmission system; and the affect of
energy use on the environmental and economics - all these raise a need to set up
polices that address energy in an integrated manner.

Yet, it was already identified that integrated polices have high bargaining costs,
transactions costs and sunk costs. These high costs in the water sector were already
found to impede ability to adapt polices to changes in the background conditions, such
as droughts, economic recessions and political changes. Physical and institutional
integration was also found to create a path dependency that decreased the ability to
adopt immediate solutions to drastic changes. In Israel, for example we found that
excessive physical and institutional integration resulted in inability to modify the existing
system to new water demands and market conditions. As a result a new water reform
was set in motion to break this path dependency created by the integrated system,
which had perpetuated the management of the existing nation wide infrastructure and
gridlock in decision making. Put it simply, IWRM conflicted with the need for Adaptive
Governance that is a requisite for addressing climate change

Given these findings, the question that I see as crucial is: should we seek a full fledge
integration between water and energy? Does this integration will not result in tremendous
costs that will outweigh the integration benefits? The answer to this paradox (of the need
for integration to internalize externalities versus the costs of integration) may be the
development of more modular governance systems. These modular systems will allow us
to decouple (and retreat from) the energy/water integration when the cost of integrations
seems high. Put it differently, maybe the real challenge is finding that balance between
the concepts of integration and independency in decision making that is required to
address emergency situations.
Andy Howe. 14/11/08
Sustainable Development Policy Advisor

    Carbon reduction and energy efficiency in the water industry – update

Steering group members are asked to note this update and provide any comments
on work-streams.

1. Background
We are conducting a two year science project (April 2007-March 2009) into increased
energy efficiency and carbon reductions in the water and wastewater sectors. The
project will:

       Identify opportunities for reducing carbon emissions in the water and wastewater
        sectors through sharing best practice, developing a robust evidence base,
        increased use of renewable energy and pollution control.

       Improve our reputation with industry and stakeholders by ensuring that our
        approach to sustainable water management and climate change objectives are

       Identify barriers and potential solutions for carbon reduction in the sector,
        especially any created by regulation. Include best practice for energy and carbon
        in our decision making.

To deliver these objectives we have work underway or completed in the following areas.

2. Sustainable supply - water supply & demand management options
In July 2008 we launched our report and model framework which quantifies the
greenhouse gas footprint of water supply and demand management measures. We used
a lifecycle approach, developing a framework to allow assessment of the carbon
implications of different supply side and water efficiency options. The results, including a
short summary of the work were published in July 2008 and forms an important part of
our new water resources strategy, due for publication in early 2009.
A key finding is that simple demand management measures – particularly those which
reduce hot water use – have significant potential to not only save water and energy, but
also to reduce the carbon footprint throughout the water system. Small actions by
individuals could together result in a significant reduction in greenhouse gas emissions,
with the added benefit of lower energy and water bills.

We have funding for a joint project with the Energy Saving Trust (EST) in 2009 to further
develop the evidence base on hot water use and energy savings in the home. We are
currently developing the specification for this project with EST and Waterwise.

3. Transforming treatment - Sewerage and wastewater
Nearing completion, this work brings together current information on the energy and
carbon associated with sewerage and wastewater treatment techniques. Of particular
interest is building the evidence base for possible solutions which could deliver carbon
reduction and achieve high water quality standards, how this might be achieved and
what policy and delivery changes this could require.
The study looks at the potential for greater efficiency and lower carbon treatment
solutions, including quick wins for the next five years. We have commissioned Atkins to
undertake this work, with peer review by Water Innovate (commercial arm of Cranfield
University). Draft report under review by the steering group, final report due December

4. Draft business plan carbon summary and case studies of low carbon solutions
We pulled together a short written summary of water company plans for greenhouse gas
emissions based draft PR09 business plans. This enabled us to advise our PR09 team
on the range of responses, level of detail and targets proposed by companies.
We have also drafted a short summary of case studies related to water industry carbon.
This includes information provided by companies in response to our questionnaire and
ad-hoc contact. Case studies typically fall into examples of deliberate low carbon
schemes, schemes which provided low carbon solutions but were not driven by this
outcome alone, as well as examples where companies feel higher energy schemes have
been required because of regulation.
5. Opportunities presented by sustainable drainage schemes and sewage as an
energy resource
Promising areas for carbon reduction relevant to the water industry is the potential of
sustainable drainage systems in reducing the amount of water reaching a sewage works
and therefore lessening energy intensive treatment and pumping required at end of pipe.
We circulated a draft specification for this work to the steering group in October and
have taken on board comments received back. We are now inviting tenders for this work.
Secondly we want to explore further than has currently been covered by Atkins, looking
into the future say 25-50 years, and consider what wastewater treatment and disposal
may look like at this time under an economy moving towards Climate Act targets. We will
commission five academic and industry experts to for their opinion on the options for
dramatically reducing greenhouse gas emissions related to the treatment of wastewater
at sewage treatment works by 2050. The outputs would be a series of short essays and
a workshop summarising these future visions. A draft specification for this work will be
presented to the steering group for comment and suggestions for innovative contributors
would be welcome.
                                                                             15 Aug 2008
Water and Energy
IWA Workshop and Reference Paper outline
Prepared by
Bo N. Jacobsen* & Gustaf Olsson**

* Member of IWA Strategic Council
   Manager, Copenhagen Wastewater R&D; Head, Planning and Development,
   Avedoere Wastewater Services, Denmark

** IWA Director, WST Editor-in-Chief
   Prof. Emeritus, Lund University, Sweden

Water and energy are inextricably linked. Energy is needed for water supply - to extract,
pump, clean and distribute water - as well as for wastewater transportation and
treatment. Energy can be produced in anaerobic treatment systems and extracted via
heat pumps in effluent water. Also, water is crucial for electrical energy generation, not
only in hydro power but also as cooling water in thermal plants. Water is a crucial
component in the production of fuels such as ethanol where the conflict between energy
and food becomes apparent.

Population growth, climate changes, urbanization and ever-rising health and
environmental standards create an increasing challenge to handle water and energy
together. At national governmental levels this is sometimes reflected by merging
ministries for environment and energy in order to coordinate the synergies and to
balance the conflicting interests.

The purpose of the water-and-energy workshop at the IWA Biennial conference 2008 in
Vienna and a subsequent reference paper is to outline the framework for interactions
with the water sector and the energy sector respectively and to formulate some IWA
positions. Based on the frameworks defined and some indicated factual information, the
paper can be used as a platform for discussions both within the IWA framework and in
dialogue with other international organisations dealing with water and energy related
topics as well as provision of structured information to the media community.
Energy use, saving and recovery at water and wastewater utilities

Water abstraction, treatment and distribution require power mainly for pumping but also
for processing during treatment. Statistics for water abstraction, treatment and
distributions are maintained by OECD and Eurostat and also by UN for different sectors.
However, the corresponding energy consumption is not recorded in the water statistics.
Some national water utility associations maintain statistics on energy consumption by
the water sector. The power consumption follows typically a diurnal, weekly and
sometimes seasonal use pattern. There is a potential for compensating some of the
diurnal use pattern by pumping to water storage reservoirs during low load hours for the
power plants and vice versa for the high load hours.

Drinking water production is increasingly crucial, in particular in dry countries. The use of
desalination is increasing at a significant rate in many industrialized countries, but this
development further emphasizes the close coupling between water and energy.

Wastewater collection, treatment and discharge, sludge treatment and disposal require
electrical power for pumping and aeration in biological treatment processes as the
dominating consumers. Statistics for wastewater generation, collection and treatment as
well as sludge generation and disposal are maintained by OECD and Eurostat and also
by UN for different sectors. As for water supply the corresponding energy consumption is
not recorded in the water statistics. Some national water utility associations maintain
statistics on energy consumption by the water sector. Energy recovery by biogas
production in anaerobic sludge digesters is quite common and the biogas may be used
for power generation, fuel for transport or heating. In some cases, installation of heat
pumps in wastewater treatment plant effluents has provided energy in terms of heat
recovery. The power consumption in wastewater treatment and transportation follows
typically a diurnal, weekly and sometimes seasonal use pattern. Stormwater handling
adds to the energy requirement. There is a potential for compensating some of the
diurnal use pattern by conducting certain treatment processes during low load hours for
the power plants and vice versa for the high load hours.
Within IWA the following special groups (SG) are considered with a direct interest in
energy issues in water and wastewater operations:
      Advanced oxidation processes (AOP),
      Anaerobic digestion (AD),
      Instrumentation control and automation (ICA),
      Strategic Asset Management,
      Sustainability in the water sector,
      Efficient Operation and Management of Urban Water Systems,
      Design, Operation and Costs of Large Wastewater Treatment Plants,
      Design, Operation and Maintenance of Drinking Water Treatment Plants.
Water use and impacts on the aquatic environment from energy production

Hydropower is often considered a “green” energy production in the sense that the
electric power production does not generate any emissions of greenhouse gases.
However, there are many signs of serious ecological impacts of hydropower generation.
The dams will not only influence the downstream transport of sediments and its
consequences for the agriculture; they also serve as giant sedimentation basins.
Eutrophication in the dams is another serious problem and evaporation from water dams
in warm countries is not sufficiently addressed as a great threat to freshwater availability.
The dams can act as physical barriers giving restrictions to migration of aquatic wildlife.
The use of water systems for recreational purposes is of course closely related to energy

Thermal power plants – both coal fired and nuclear – require large amounts of cooling
water. For example, in the USA almost 40% of the withdrawn freshwater is used for
cooling in thermoelectric plants. The heating of the water and the risk for radioactive
contamination present great challenges. Also any addition of inhibitors, anti-scaling
agents, biocides (in cooling towers) may represent high environmental loads of
hazardous substances, although at relatively low concentrations.

It is quite apparent that the water quantity and quality aspects are not always placed
sufficiently high on the agenda for many power companies. Here IWA may be a
cooperating partner with the energy sector to establish professional networks dealing the
close relationship between water and energy.
It is obvious that energy savings in households and in industry will have a large impact
on the need for electrical energy and consequently on water consumption and ecology.
For example, using more efficient pumps and power electronic motor control as well as
more efficient refrigerators, air conditioners and heating systems will offer a most
significant impact on the total electrical energy use.

An ironic fact in developing countries is that low cost asynchronous motors and pumps
have increased the water extraction for the agriculture. In some cases this has had
catastrophic consequences for the groundwater level and for the salinity of the soil.
Better use of water for agriculture is therefore of paramount interest.

Within IWA the following special groups (SG) are considered with a direct interest in
issues related to energy from water and environmental impacts from energy production:
      Anaerobic digestion
      Assessment and control of hazardous substances in water (dealing with
       inhibitors having potential impacts on ecotoxicity, persistency and
      Biofilms (dealing with control of fouling on material surfaces exposed to water)
      Climate Change and Adaptation
      Instrumentation control and automation (ICA)
      Strategic Asset Management
      Sustainability in the water sector
      Watershed and River Basin Management

Emerging issues

Future water supplies and treatment will probably be more energy intensive. Readily
accessible freshwater supplies are limited and have been fully allocated in some areas.
This means increased energy for pumping at deeper depths and longer conveyance.
New technologies to access and to treat non-traditional water resources will require
more energy per m3 of water. The water resources can be sea water, brackish water,
produced water or impaired water.
Many new technology issues offer interesting solutions. Wave energy can offer not only
sustainable solutions of energy generation. The combination of desalination plants and
wave energy generation could be a very interesting area for research and development
for IWA researchers in cooperation with power systems researchers. Microbial fuel cells
offer another interesting combination of water and energy issues. The MFC is not only
an interesting energy challenge but also offers sustainable treatment of biological
substances as a by-product.

To extract heat from effluent water in treatment plants does not require new technology
research but can probably be applied much more. Of course such a development
assumes a relevant infrastructure, for example district heating systems.

It is obvious that new incentives and attitudes have to be developed in order to save
water and save energy. This is also a crucial role for IWA.


Energy and water has been selected as a crosscutting track at the IWA WWC in Vienna
2008. The inputs generated at one full day workshop together with keynote
presentations will generate the background for a reference paper. Such a reference
paper is meant to outline the framework for interactions with the water sector and the
energy sector, respectively and to formulate some IWA positions.

COP15, the next UN Climate Change Conference will take place in Copenhagen 30 Nov.
– 11 Dec. 2009. It is expected that this will also focus on energy consumption and
energy savings. In order to highlight the potentials for energy savings and recovery by
the utilities in the water sector, it may be an opportunity for IWA to get involved in
organising inputs for this planning process.

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