seminar ii presentation

Cost and Energy Implications of Water Recycling in Buildings

Seminar II | Final Review

Presented by Sanskriti Tiwary

MBEM | SPA Delhi

Sanskriti Tiwary | BEM 539 | MBEM | SPA Delhi 30-07-2015

WATER is important!!

Uti

litie

s o

f W

ATE

R


• Over 2.5% the world’s water is fresh but frozen, locked up in Antarctica, the Arctic and glaciers, and not available to man.

• Thus humanity must rely on this 0.5% for all of man’s and ecosystem’s fresh water needs.

• An Indian on an average gets 142 LPCD (52 m3 per capita per year) of fresh water.

Source- A report on water by World Business Council for Sustainable Development

The Global Water Situation P

er

Cap

ita

Use

of

WA

TER


Sewage Treatment

Mo

vin

g B

ed

Bio

Re

acto

r


“Water Specific Energy Efficiency in Built Environment”

Thesis, Department of Building Engineering and Management,

School of Planning and Architecture, New Delhi

by Rashmi Sharma (2013)


S.No. Project Names

Built

up area

(m2)

Water

consumed

(Kl)

Water

consumed /

built up area

(Kl/m2)

Overall

Energy

Consumptio

n

(KWHR/kl)

Water Supply &

distribution

energy

Consumption

(KWHR/kl)

WTP

Energy

Consumpti

on

(KWHR/kl)

Recycling (STP)

Energy

Consumption

(KWHR/kl)

Energy

consumed for

water per unit

area- Energy

consumed-

water/m2

(KWH/m2)

1 ASF SEZ project at Guwalpahari,

Gurgaon 12744 220 0.01 5.74 1.58 0.46 3.68 0.01

2 B.P.T.P Basai at Sector-37,

Gurgaon 164975 1120 0.01 4 0.95 0.09 2.95 0.01

3 Ireo Group housing at sector 67

A, Gurgaon (Plant Room- 1) 48500 300 0.01 5.96 1.63 0.21 4.05 0.01







7 Ireo Group housing Panchkula.

Haryana 254898 1585 0.01 3.71 0.64 0.13 2.93 0.01

8 Victoria garden housing,

Azadpur, New Delhi 32145 450 0.01 4.9 0.92 0.26 3.51 0.01

9 Kashish developer, group

housing, sector 111,gurgaon 145893 740 0.01 3.61 0.67 0.11 2.62 0.01

10 Housing, Kathmandu, Nepal 34351 240 0.01 6.04 1.54 0.47 3.37 0.01

11 La Lagune, Gurgaon 71128 420 0.01 5.95 0.99 0.17 4.34 0.01

Total average 85070.4 577.3 0.01 5.1 1.2 0.2 3.5 0.01

Housing


S.

No.

Project Names (Small

scale offices)

Built up

area (m2)

Water

consum

ed (Kl)

Water

consumed/

built up

area

(Kl/m2)

Overall

Energy

Consumption

(KWHR/kl)

Water Supply &

distribution

energy

Consumption

(KWHR/kl)

WTP Energy

Consumptio

n (KWHR/kl)

Recycling (STP)

Energy

Consumption

(KWHR/kl)

Energy consumed

for water per unit

area- Energy

consumed-

water/m2

(KWHR/m2)

1 Arcop office, Nehru

place, New Delhi 12138 20 0.01 10.46 6.45 3.2 1.08 0.01

2

Unesco officve

building,chanakyapuri,

New Delhi

28322 20 0.01 12.95 9.25 2.74 0.99 0.01

3

Corporate office,

Jaypee greens, sector

128, Noida (Common

Plant room)

39037 105 0.01 10.14 8.5 0.52 0.78 0.01

Total average 26499 48.3 0.01 11.2 8.1 2.2 0.95 0.01

S.N

o. Project Names

Built up

area (m2)

Water

consum

ed (Kl)

Water

consumed/

built up

area

(Kl/m2)

Overall

Energy

Consumption

(KWHR/kl)

Water Supply &

distribution

energy

Consumption

(KWHR/kl)

WTP Energy

Consumption

(KWHR/kl)

Recycling (STP)

Energy

Consumption

(KWHR/kl)

Energy consumed

for water per unit

area- Energy

consumed-

water/m2

(KWHR/m2)

1 Indus hotel,paschim

vihar, Delhi 26299 580 0.01 6.89 1.09 0.31 2.69 0.01

2

Manor hotel, New

firiends colony, New

Delhi

22253 35 0.01 6.71 1.95 0.56 3.63 0.01

3 Hotel Broadway,

Srinagar, J& K 20230 35 0.01 6.63 1.87 0.71 3.25 0.01

Total average 22927.3 216. 7 0.01 6.7 1.6 0.5 3.2 0.01

Offices

Hotels


28

72

Water Supply &distribution energyConsumption(WHR/kl)

Recycling (STP)EnergyConsumption(WHR/kl)

Offices

26

74

Water Supply &distributionenergyConsumption(WHR/kl)

Recycling (STP)EnergyConsumption(WHR/kl)

%

%

%

%

Housing

33

67

Hotels

%

%


Need for the Study

• The trend observed from the data collected as a part of the earlier study is that almost two thirds of the energy consumed by water is used up in waste water treatment and only one third is actually required to treat and distribute the fresh water supply. This implies that the major portion of energy consumed by water is embodied by the treated water coming out of the STP, which is in most cases not reused.

• The absence of proper study and norms indicating the relationship between energy consumed and the treatment of waste water gives rise to the need for this study. It is a requirement of the present building industry to sensitize the stakeholders involved towards the energy invested in treatment of waste water and its proper recycling and reuse.


Domestic Water consumption per Capita per Day (in litres)

The Domestic Water Situation in Indian Cities ...

... &

Del

hi

Source- Water Poverty in Urban India: A Study of Major Cities by ABDUL SHABAN, Tata Institute of Social Science, Mumbai


• 72.7 % of Delhi’s households get to consume less than 100 LPCD of fresh water.

• There still exists 10.4 % of households that consume more than 135 LPCD of fresh water.

• Similar pattern can be seen in the other 6 major cities of India.

Source- Water Poverty in Urban India: A Study of Major Cities by ABDUL SHABAN, Tata Institute of Social Science, Mumbai


The Sewage Water Cycle

Energy Energy

Sewage Treatment Plant (Water Recycling Plant)


Water Energy

?

Importance-o-meter


Aim & Objectives

• To check the existing data for validation and authenticity

• To collect realistic data from buildings in operation

• To compare the data collected amongst buildings of same typology and scale

• To arrive at relationships between size of building and energy consumed in water recycling

• To arrive at relationships between volume of water consumed and energy consumed in water recycling

The study aims at establishing a relationship between the volume of water being treated and energy invested in this water in the process of recycling.


Scope & Limitations Amount of water consumed, sewage generated, energy consumed, amount of treated water generated and utility of the treated water fall under the scope of the study. Residential and office occupancies are considered for the study. Data for the case studies are collected from NBCC and PWD. Previous years’ work by Rashmi Sharma on Water Specific Energy Efficiency in Built Environment is treated as a source of data.

Metering errors and leakages are not audited. Population is calculated considering the trend prevalent for operational data. Seasonal variations in water consumption and sewage generation are not accounted for.


Methodology


Determinants for Data Articulation

v/s Water Consumed

Sewage Generated

Total Energy Consumed

Energy Consumed (STP)

Energy Consumed (Supplying)

Energy Consumed (WTP)

Population

Built up Area

Water Consumed

Power Factor (STP)

Power Factor

(Supplying)

Power Factor (WTP)


Power Factor Ratio


Case Study I : Indira Paryavaran Bhawan

Ministry of Environment and Forests

The cost of the project is projected to be Rs. 201.49 crores. The building is RCC framed structure with 3 basements and one G + 6 tower and another G+ 7. Total plot area : 9565.13 Sqm Basement area : 11826 sqm Super structure area : 19088 sqm Total Built up Area : 30914 sqm Green Area : 5010 sqm

Project is Under Commissioning and shall cater to 900 people including the employees and the floating population. Design Data is considered for case study.


Water is being supplied to an underground tank of 1 lakh litres capacity by municipal supply. It is then pumped to four sets of over-head tanks of 50 KL capacity each (15+15+20 KL) thus making it 2 Lakhs litres. It is supplied to the four toilet blocks for drinking, moping, washing and flushing. The soiled water by gravity reaches the STP in the basement (30 KLD Capacity). The water treated in the STP is in turn used for Horticulture purposes on site.


Parameters Value Unit

Total Water Consumption 37 KL

Total Sewage Generation 30 KL

Total Population 900 Persons Energy consumption in supplying fresh water 45 KWHr

Energy consumption in STP 134 KWHr

Energy Factor (Domestic Water supply) 1.22 WHr/L

Energy Factor (Recycled Water) 4.47 WHr/L

LPCD Water Consumption 41.11 LPCD

LPCD Sewage Generation 33.33 LPCD

INPUT Design Data

OUTPUT Analysis Data


Residents Servents Total Units Population

Bunglows Type 8 3 6 9 14 126

Bunglow Type 7 3 3 6 102 612

Type 6A 3 1.5 4.5 376 1692

Total 492 2430

Case Study II : New Moti Bagh

Total site Area : 105 Acres Green Area : 60 Acres Built up Area : 35 Acres

Parameters Inlet Water Treated Water

pH 7.5-8.5 6-8.5

TSS 250mg/l <20mg/l

COD 450mg/l <70mg/l

BOD 300mg/l <10mg/l


10% Losses Unaccounted 9% STP losses

87 KL Assumed 221 KL (25%) 50 KL

STP Treated water

560KL Assumed 510 KL (59%)

Horticulture

1088 KL EWS 684 KL

220 KL

Horticulture

Borewell

147 KL

Two supplies

from NDMC

New Moti Bagh Residential Colony : Water Balance Equation on 10th

Sept'13

Municipal Sewer Line

Bunglows / Apartments

868 KL

10% Losses Unaccounted 10% STP losses

80 KL Assumed 182 KL (23%) 54 KL

STP Treated water

542KL Assumed 488 KL (61%)

Horticulture

1009 KL EWS 638 KL

205 KL

Horticulture

Borewell

150 KL

New Moti Bagh Residential Colony : Water Balance Equation on Average data for a week in Sept'13

Bunglows / Apartments

804 KL

Two supplies

from NDMC

Municipal Sewer Line

The

Gre

y A

reas

in t

he

Wat

er B

alan

ce E

qu

atio

n


• Car Wash – Each house has 3 car parking units reserved – No common provision for car wash – Potable water is being used for houses

• Life style – A huge number of in-house domestic help/security persons – Regular moping/cleaning – Excessive use of water

• Domestic Help – Awareness regarding water is lacking in the domestic help

• Irrigation – Irrigation on individual dwelling units level are found to be using

potable water

• Leakages • Metering errors

List of Unaccounted Water Losses


Parameters Value Unit

Water consumption 804.14 KL

Sewage Generation 542 KL

Population 2430 Persons

Energy consumption in supplying fresh water 271.43 KWHr

Energy consumption in STP 653.66 KWHr

Actual water recycled 488.57 KL

Percentage Water Recycled 60.76 %

Energy Factor (Domestic Water supply) 0.34 WHr/L

Energy Factor (Recycled Water supply) 1.34 WHr/L

Actual Avg. LPCD Water Consumption 330.92 LPCD

Actual Avg. Sewage Generation 223.05 LPCD

INPUT Operation Data

OUTPUT Analysis Data


Data from Previous Works

v/s

Water Consumed

Sewage Generated

Total Energy Consumed

Energy Consumed (STP)


Energy Consumed (WTP)

Population

Built up Area

Water Consumed

Power Factor (STP)

Power Factor

(Supplying)

Power Factor (WTP)


Power Factor Ratio

0

50

100

150

200

250

300

350

400

450

500

1 2 3 4 5 6 7 8 9 10 11

LPCD Fresh Water Consumption

0.00

0.02

0.04

0.06

0.08

0.10

0.12

0.14

0.16

0.18

0.20

1 2 3 4 5 6 7 8 9 10 11

Water consumed / Built up area (Kl/m2)

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

1 2 3 4 5 6 7 8 9 10 11

Energy consumed for water per unit area (KWHr/m2)

0

2

4

6

8

10

12

14

1 2 3 4 5 6 7 8 9 10 11

Energy Consumption per liter water (KWHR/kl)

0

1

2

3

4

5

6

7

8

9

10

1 2 3 4 5 6 7 8 9 10 11

Energy Factor for Recycling (KWHR/kl)

0

1

2

3

4

5

6

7

8

9

10

1 2 3 4 5 6 7 8 9 10 11

Energy Factor for Water Supply (KWHR/kl)

0

1

2

3

4

5

6

7

8

9

10

1 2 3 4 5 6 7 8 9 10 11

Energy factor Ratio (Recycling / Fresh Supply)

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

1 2 3 4 5 6 7 8 9 10 11

Energy factor for WTP (KWHR/kl)

01

234

56789

10

1 2 3 4 5 6 7 8 9 10 11

Energy consumed for water per person (KWHr/person)


Energy efficiency Codes and green building rating systems such as GRIHA, IGBC, USGBC, LEED, etc. advocate usage of recycled water for various purposes. Most of the Green Building Rating systems provide limited additional points for water recycle and reuse in buildings.

GRIHA provides extra one point for every 25% increase in annual water reuse. These rating systems consider use of recycled water and rain water under same head. In India, treated water is not recommended for drinking or any other purpose where human contact is possible. The study of energy and water issues in Indian as well as International green rating system reflect the lack in attention being given to energy consumed in treating waste water and its reuse.

The data from previous works’ case study indicates a significant amount of energy being invested in waste water treatment. The study of research papers shows the rising awareness about embedded energy in water.

Conclusion


79

21

Indira Paryawaran Bhawan

Energy factor(Recycling)

Energy factor(Supplying)

%

%

Power Factor Ratio

80

20

New Moti Bagh

%

%


Conclusion

Water consumption per unit Built up Area Range

Housing 0.01-0.02 KL/m2

Offices 0.001-0.003 KL/m2

Hotels 0.002-0.02 KL/m2

Energy consumption per unit Water Range

Housing 4-6 KWHR/KL

Offices 10-12 KWHR/KL

Hotels 6.6-6.9 KWHR/KL

Energy consumption per unit Built up Area Range

Housing 0.01-0.07 KWHR/m2

Offices 0.01-0.03 KWHR/m2

Hotels 0.01-0.15 KWHR/m2


INDIRA PARYAVARAN BHAWAN • The proposed usage of recycled water is toilet flushing and horticulture.

– Use of recycled water for toilet flushing is under debate, no provision is made for the same yet.

• The recycled water is proposed to be used for horticulture purpose on site. Approximately 30 KL of water is expected to be recycled every day as per the capacity of the STP. The water to be recycled is more than twice the requirement of the irrigation. It costs approx. Rs. 1.6 lakhs per year.

• Being an office building, the LPCD Water Consumption (41 LPCD) and LPCD Sewage Generation is lower. NBC 2005 recommends 45 LPCD for offices.

• There is a relation between water consumption / sewage generation and the energy factors (fresh water / recycled water) – Energy factors are high when the water consumption and sewage generation

are lower.

Conclusions & Recommendations

Water Requirement

CPWD standards 3000 Gallons/Acre

Proposed on site 30KL/1.2Acres = 7925 Gallons / 1.2 Acres

=6604 Gallons / Acre


NEW MOTI BAGH • The fresh water consumption per dwelling for the

bungalows/apartments are too high as compared to the EWS flats. • The recycled water is being used only for horticulture, the utilities

of recycled water may be increased keeping in view the level of quality to which the sewage is treated.

• Potable water is being used in large quantities for car wash – water efficient car wash system may be installed – recycled water may be used for the purpose in the least

• Per capita domestic water consumption per day is too high, steps should be taken to reduce the water demand. – Leakage repairs – Low flow fixtures – Awareness programmes



NEW MOTI BAGH • Unaccounted water losses are too high, only 60% of the fresh water

consumed is being recycled. – Water audit – Mitigation measures

• Solar water geysers are in place on each building, however they were not found to be in use and electric heaters are as well provided in each residence.

• Even though recycled water is being used for irrigation, a sizable amount of water (150 KL) is taken from a borewell for irrigation purposes, which is less than the unaccounted water losses and could have been avoided with a more efficient system.


Water Requirement

CPWD standards 3000 Gallons/Acre

On site in use 680KL / 60Acres = 2993 Gallons / Acre


• The study concludes that the energy consumed by water in recycling is a lot more than the energy consumed by water at other stages in buildings. Thus modified regulations and norms are recommended so as to encourage more efficient, justifiable and innovative utilisation of the recycled water that is high on invested energy.

• Norms are required for auditing and maintaining STP’s efficiency.

• Norms are necessary for auditing not just the STP’s efficiency but also the efficiency of the whole water cycle from fresh water intake at the site to recycled water generation for checking water losses.

Recommendations


Addams, L..G.B.M.K.a.M.S. (2009) 'Charting Our Water Future: Economic Frameworks to Inform Decision-making', http://www.mckinsey.com/App_Media/Reports/Water/Charting_Our_Water_Future_Full_Report_001.pdf.

Aquastat (2003) 'Information System on water and Agriculture'.

Central Pollution Control Board, [Online], Available: http://www.cpcb.nic.in/Water_Quality_Criteria.php [29 Nov 2013].

Feldman, M. (n.d) 'Aspects of energy efficiency in water supply systems '.

Garg, N.K.a.Q.H. (2007) 'Alarming Scarcity of', Current Science. Vol 93, No 7, 10 Oct, pp. 932-941.

Google Maps, [Online], Available: https://maps.google.co.in/.

indira paryavaran bhawan, [Online], Available: http://www.indiraparyavaranbhawan.com/.

Ministry of Environment and Forests, [Online], Available: http://moef.nic.in/.

Narsimhan, T.N. (2008) 'A note on India's water budget and Evapotrasnpiration, Vol 117. No 3.', Journal of Earth System Sciences, pp. 237- 240.

Revenga, C. (2000) 'Will there be enough water?', EarthTrends, October.

Shaban, A. (n.d) 'Water Poverty in Urban India: A Study of Major Cities', Tata Institute of Social Science, Mumbai.

Sharma, R. (2013) Water Specific Energy Efficiency in Built Environment, Thesis edition, New Delhi: School of Planning and Architecture.

UNEP, W.&. (1998) 'Industry, Fresh water and sustainable development'.

UNICEF (n.d) 'Water in India: Situation and Prospects'.

Verma, S.a.S.P. (2007) 'India's Water Future 2050', International Journal of Rural Management, vol. 3, no. I, pp. 149-79

'Water Facts and Trends', Development World Business Council of Sustainable.

World water week, [Online], Available: www.worldwaterweek.org/onthewaterfront3

References

seminar ii presentation

Documents

worlds water

unit area energy

year of fresh water

mbem spa delhi30

sanskriti tiwary bem

area m2 water consum

gurgaon plant room

ecosystems fresh water