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Technical Study:Survey & Studies for Development of Guidelines for Optimisation of Water & Waste Water Usage in Coal Based Thermal Power Plants

June 2013 - August 2014


1. Name of Research Station and Address:
Excellence Enhancement Centre for Indian Power Sector 
West Block – 2, Wing No. 5, 
R.K. Puram, New Delhi – 110066
2. Project Title:
“Survey and Studies for Development of Guidelines for Optimisation of Water & Waste Water Usage in Coal Based Thermal Power Plants”
3. Introduction & Background:
With its continuously declining per capita water availability (from about5,177 m3 in 1951 to 1,654 m3 in 2007),India stands water stressedand is close to being categorized ‘water scarce’.Water demand inIndia is expected to grow annually by 2.8 per cent to reach 1,500 bcm(by 2030) while the current supply is only about half (viz.,744bcm).



The Government of India, in its National Water Mission (NWM)under the National Action Plan on Climate Change (NAPCC), hasemphasized the need to develop a framework for optimizing wateruseefficiency by 20 per cent, through regulatory mechanisms withdifferential entitlements and pricing. It further emphasizes the needto focus on integrated water resource management through waterconservation, wastewater minimization, etc. This would requirevarious sectors, including industries, to optimize their practicesensuring conservation, recycling, and reuse.
The total power generation capacity of India (as on 28Feb. 2013) was 211766 MW and 34444.12 MW in captive power plants. It is planned that almost 67000 MW will be added in the 12th Plan. The typical water requirements of a 200 MW unit are as given below:
Quantity m3/hr with ash water recycling
Consumption m3/MW
Ash Handling
Cooling Water
DM Water
Drinking Water (Plant + Colony)
Coal Handling
Fire Fighting

Some typical water requirements for different type of thermal power plants are as indicated below:

Power Plant Type
Range m3/MW
Gas based power plant
1.7 – 2.0
Coal based Plants with total dry ash handling system
3.0 – 3.5
200 MW Coal based Power Plant with once through cooling
3.0 – 3.5
200 MW Coal based Power Plant with cooling towers
4.5 – 5.0
200 MW Coal based Power Plant with ash water recycling
3.5 – 4.0
500 MW Coal based Power Plant with cooling towers
4.0 – 4.5
500 MW Coal based Power Plant with ash water recycling
3.0 – 4.0
110 MW Coal based Power Plant
7.0 – 8.0

4. Objectives:
Even though efforts have been made to optimize water use at newer power plants as indicated below:


1 X 500 MW

2 X 660 MW

Evaporation & Drift from CT
HVAC System Losses
Potable Water System
Evaporation losses in Ash Dyke
Losses in Cycle make up
Losses in Service Water System
Evaporation Losses in Reservoir
Total Consumptive Water
Water for Ash Handling
Water recovered in AWRS
Additional Make up
Total Water Drawl

33 Cusec (Max)

38 Cusec (Normal)
50 Cusec (Max)


However; still many of the existing power plants are operating with high level of specific water consumption. Water is increasingly becoming a premium commodity in terms of both cost and availability. There is need and scope of reducing water consumption in power plants especially in water stressed areas. The objectives of the proposed study are:
1. To carryout actual water audit/water balance survey at two power stations in water scarce areas such as Rajasthan and Gujarat to assess the actual water usage and identify potential areas of water consumption reduction and water recycle/reuse. 
2. Based on water audit/water balance survey studies at two power stations develop guidelines for conducting water audit/water balance survey at power stations and identification of potential areas of water consumption reduction, water recycle/reuse at other power stations.
3. The study will also work out cost benefit analysis of the viable options taking into account the opportunity cost/value of water use.
4. It will also try to capture impact of seasonal variations of water quality on plant performance and evolve strategy for optimal water use.   
5. Justification 
Water as a natural resource is fundamental to life and sustainable development. However, it is a scarce resource. India has more than 17% of world’s population, but has only 4% of world’s renewable water resources. The present scenario of water scarcity has given rise to many concerns such as:
I. Large parts of India have already become water stressed. Water scarcity is expected to grow more acute as water demands from the power generation, agriculture, industrial and municipal sectors all increase. 
II. Thermal Power Plants require large amounts of water for cooling and generation. Setting up of new plants is getting constrained due to difficulty in water linkages. 
III. There has been less attention towards management of water resources. Water resources projects are being implemented without giving due consideration to its optimum utilization.
IV. Proper water utilization can also help in improving the performance, availability & reliability by proper treatment/selection of treatment technology thus providing an incentive to power stations. 
6. Drivers for the Studies:
  • National Water Mission
  • National Water Policy
  • Non-Availability of Quantity & Quality of Water for specific application
  • Improving Water Efficiency
  • Cost Reduction & Resource Conservation
  • Sustained Growth and Environmental Considerations
  • Statutory Requirements
  • Plant Operational requirements  
  • Selection & Availability of suitable Technology
  • Increasing Efficiency of Water Intensive Cooling Systems
  • Reducing Energy Consumption in Water Systems
7. Benefits/returns from the facility 
Considering the fact that water availability is getting increasingly reduced and also the cost of water is increasing, the study is aimed to identify the areas in which the water consumption can be reduced and also to identify the possibility of its alternate use within the plant such as additional capacity addition (which otherwise is not feasible due to non-availability of new water linkages) or through other alternative uses in the nearby region.     
The case study would provide a model for others to adopt the best practices in water use efficiency. It may also help in evolving policy guidelines for efficient water usage. The major benefits expected are:
(1) Establish a thorough accounting of water usage throughout the power plant and establish a crediblemethodology that can be used for future studies,
(2) Provide a baseline set of cases and water loss data for assessing potential improvements andevaluating R&D programs, and
(3) Provide a basis for comparing water usage in various types of advanced power systems.
8. Technical Programme
In thermal power plants, the water is classified based on two major parameters, i.e, as per Quality specification and Usage consideration.  
The various systems include the following:
- Raw water
- Service water
- De mineralized water
- Cooling or Re circulating water
- Fire Hydrant water
- Drinking water
- Waste waters
- Ash water 
Generally there is no systematic measurement of total water flow in the plant. Water audit/water balance survey would be organized through a service provider at selected coal based thermal power stations in Rajasthan & Gujarat. The study will adopt the following strategies for the water audit/water balance survey at the power stations and for developing the guidelines for such studies at other thermal power plants:
A. Appointment of a Consultant for the study: Any water optimization, recycling or resuse study involves knowledge of effects of water quality on power plant performance, availability, reliability, possible corrosion; fouling; scaling &biofoulingin the water touched surface by varying water quality/quantity parameters, water & wastewater treatment technologies, etc, a specialist involved with such studies in power sector will be appointed as a Consultant for the studies. Consultant will help in carrying out the studies, interpretation of data obtained and help in developing the guidelines for the proper water audit/ water balance survey & optimized use of water at power plants.
B. Preliminary visit by the EEC team & Consultant: Team members of EEC and Consultant will undertake visit to the identified stations to acquaint themselves with existing water systems and problems being faced by the stations. Based on the preliminary visits to the stations, the scope & methodology of appointing an external agency for carrying out the water audit/water balance survey would be finalized and the agency would be appointed.
C. Water Audit/Water Balance Survey by external agency: The appointed agency is expected to carry out the following activitiesfor the studies.This is an indicative list but not limited. Actual scope & methodology would be finalized by the study team & the Consultant after visit to the identified stations. Consultant will coordinate & oversee the activities by the external agency. Consultant will also visit the stations during the studies to ensure completeness of the studies.
1. Measurements:
a) For flow measurement of major stream where flow meter is not installed and same flow also counter checked by measuring second time, flow is measured by ultrasonic flow meter.
b) Wherever flow meter is available, flow is considered from its readings.
c) Also, pressure readings are taken from pressure gauges installed in discharge lines of water pumps.
d) Power drawn by the water pumps is measured
e) For cooling tower, air velocity is measured by anemometer and thermo-hygro meter measures humidity of inlet and outlet air.
f) Operation hours and other details like rated capacity, types of pumps, mode of operation of pumps, present controls of operation etc are discussed with company authorized persons.
2. Field Survey:
a) Audit team to find opportunity for the efficient operating condition personally inspected each stream of water.
b) Audit team will measure the parameters as per 1 above.
3. Reporting:
Report will be prepared based on scope of study and actual findings as per details given below.
a) Flow charts are prepared based on operation.
b) Theoretical pump efficiency evaluated based on rated capacity of pumps and motors.
c) Actual pump efficiency evaluated based on measured parameters like flow, pressure and power.
d) Water balance has been carried out based on actual measurements.
e) Characterization of water is been evaluated based on samples collected by team and analysed at lab.
f) Recommendation for improvement with respect to pump efficiency, recycle and reuse, other water losses etc. has been assessed by our experts after study of evaluated parameters and based on latest practices employed by various users worldwide.
- Pump efficiency
- Recycle and reuse
- Water losses inventory
- Identifying avenues for the application of latest technology for the overallimprovement in water management and water conservation.
D. Development of guidelines for conducting water audit/water balance survey, optimization of water use, improving water efficiency, identification of potential water recycling/reuse opportunities for other power stations: Based on the outcome of the water audit/water balance survey at the two identified power stations, detailed guidelines would be prepared for conducting water audit/water balance survey and optimizing/improving water use efficiency including water recycling/reuse and improving plant performance of all water touched equipment.

9. Scope of work
The scope of work would cover but not limited to the following:


- Data collection on the basis of design/as built systems of various water circuits.
- Flow measurements for carrying out the water balance. 
- Inlet water quality parameters measurement.
- Outlet waste water quality assessment to enable its possible treatment/recycling.
- Develop water balance and water conservation assessment. 
- Identification of process/system modifications for reducing water consumption. 
- Identification of options for economic usage of the water so saved along with their cost benefit analysis. 
10. Facilities required
Existing facilities and skills available in EEC would be used to the extent available, the remaining skill sets, supporting technical experts and field activities will be outsourced. The services of temporary staff to assist in the project will also be hired. 
11. Principal Investigator and Project Team     
To be provided by EEC, supported by external experts/agencies.
12. Deliverables of the project
1. Report on water audit/water balance survey of two identified stations giving recommendations for improving the water use efficiency, potentials for improving plant performance/reliability/availability through adoption of alternate technologies/treatments, potential for recycle/reuse of waters & wastewaters or near zero liquid discharge, cost benefit analysis of improving water use efficiency, identify possible alternate water source for sustained operation of the power plants, etc.
2. Guidelines for other power stations to carry out similar studies and improve their water use efficiency.
3. Provide framework for development of policy guidelines for water use in power plants and possible utilization of water leaving the premises of the power stations for other users or meeting the statutory requirements.  
13. Completion period
Total duration of the project: 12 months

Time (from the date of project approval)

Appointment of Consultant
1 Month
Identification of power plants for the studies
1 Month
Visit of the Project Team & Consultant to the identified power stations & preparation of TOR for the appointment of the external agency for carrying out water audit studies at two stations
2 Months
Appointment of external agency for the studies at two stations
3 Months
Water audit/water balance survey and submission of the final reports by the agency for two identified stations
7 Months*
Preparation of guidelines with recommendations for other power stations
10 Months
Submission of final report to the Govt./sponsoring agency
12 Months

*Presuming only one team is working at a time
(Details given in excel sheet)



A. This proposal has the approval of the Organization and all the existing facilities shall be made available for carrying out the studies on the proposed scheme.
B. That the research work proposed in the scheme does not in any way duplicate the research work already done or being carried out in the research station on the subject.
C. That the project is not being partly or fully financed by grant from any other Organization/Government. 

Name and Signature of the Principal Investigator

Signature of the Head of the Institution/Organization