Presentation from Sustainex 2013

1. Water Efficiency
Richard Barnard

2. WHY LOOK AT WATER?
• Water availability – it is a finite resource and we don’t want to
run out.
• Costs – water costs money – often much more than we think.
• Legal and regulatory reasons – eg Pollution Prevention and
Control (Industrial Emissions) Regulations (Northern Ireland)
2012, The Water Supply (Water Fittings) Regulations (Northern
Ireland), etc.
• Corporate requirements (eg CSR Reporting); and
• Good business sense !

3. WATER AVAILABILITY
Rainfall in Northern Ireland is very
varied.
Wettest:
Killeter Forest - 1950 mm
Driest:
Lough Neagh - 800 mm
Source: Met office
To compare:
Khartoum, Sudan - 155 mm
Tripoli, Libya - 271 mm
Athens, Greece - 371 mm
Paris, France - 607 mm
Rome, Italy - 802 mm
Sydney, Australia - 1222 mm
Source: worldweather.com

4. 1 2
3
Incoming
water meter
48956.8
Water supply:
- standing charge £
- volumetric charge £/m3
Wastewater disposal:
- standing charge £
- sewerage volumetric charge £/m3
- trade effluent charges £/m3
water in
WHERE DO COSTS ARISE?
added value
wastewater out

5. 1 2
3
Incoming
water meter
48956.8
Water supply:
- standing charge £
- volumetric charge £/m3
Wastewater disposal:
- standing charge £
- sewerage volumetric charge £/m3
- trade effluent charges £/m3
water in
WHERE DO COSTS ARISE?
wastewater out

6. MAINS WATER CHARGES
2012/13 tariffs
Northern Ireland Water
Supply Pipe Size Water
Up to 20mm £70
Over 20mm up to 25mm £117
Over 25mm up to 40mm £213
Over 40mm up to 50mm £335
Over 50mm up to 75mm £660
Over 75mm up to 100mm £1,195
Over 100mm £1,697
Standing charges

7. MAINS WATER CHARGES
2012/13 tariffs
Northern Ireland Water
Discount Water
Standard volumetric charge per m3 107.8p
Large user volumetric charges:
(100,000 – 250,000m3) 20% 86.2p
(250,000 – 500,000m3) 25% 80.9p
(Over 500,000m3) 30% 75.5p
Variable charges

8. WASTEWATER ?
Usually either to:
• Foul sewer (regulated by NIW)
- Domestic wastewater (Sewerage charges)
- Trade effluent (TE consent and Trade Effluent Charges)
• Waterways or underground strata
Under the Water (Northern Ireland) Order 1999, the consent of the
Department of Environment is required to discharge any trade or
sewage effluent into waterways or underground strata.

9. 1 2
3
Incoming
water meter
48956.8
Water supply:
- standing charge £
- volumetric charge £/m3
Wastewater disposal:
- standing charge £
- sewerage volumetric charge £/m3
- trade effluent charges £/m3
water in
wastewater out
WHERE DO COSTS ARISE?

10. SEWERAGE CHARGES
2012/13 tariffs
Northern Ireland Water
Supply Pipe Size Sewerage
Up to 20mm £80
Over 20mm up to 25mm £134
Over 25mm up to 40mm £243
Over 40mm up to 50mm £383
Over 50mm up to 75mm £755
Over 75mm up to 100mm £1,366
Over 100mm £1,942
Standing charges

11. SEWERAGE CHARGES
Remember: non-return to sewer allowance. It will be 5% unless it has been agreed
with NIW that a different allowance will be applied
2012/13 tariffs
Northern Ireland Water
Sewerage
Standard volumetric charge per m3 173.3p
Variable charges

12. Charge (p/m3) = R + V + B x Ot + S x St
Os Ss
R = reception and conveyance (20.78 p/m3)
V = primary treatment (23.43 p/m3)
B = biological oxidation settled sewage (15.52 p/m3)
S = treatment & disposal of primary sludge (18.09 p/m3)
Os = COD crude sewage settled 1 hr (332 mg/l)
Ss = total suspended solids crude sewage (247 mg/l)
Ot = COD of trade effluent (mg/l)
St = Suspended solids of trade effluent (SS) (mg/l)
TRADE EFFLUENT CHARGES
= 77.82 p/m3
2012/13 tariffs
Northern Ireland Water

13. 1 2
3
Incoming
water meter
48956.8
Water supply:
- standing charge £
- volumetric charge £/m3
Wastewater disposal:
- standing charge £
- sewerage volumetric charge £/m3
- trade effluent charges £/m3
water in
wastewater out
WHERE DO COSTS ARISE?
added value

14. Easily
Identified
Costs
Hidden
Costs or
Added
Value
Cost of water treatment
Loss of product/in sales value
Cost of raw materials in effluent
Cost of effluent treatment
Cost of wasted energy, eg heating, pumping
Water Charges
Sewerage Charges
Trade Effluent Charges
WHAT OTHER COSTS?

15. m3/min x head (m)
kW = 6.1 x pump efficiency
With an overuse of water of, say,100 m3/h used on first floor of a building
then unnecessary power consumed through pumping may be given from:
= 1.66 x 15
6.1 x 0.6
= 7 kW
At 7.0p/kWh and 16h/d operation, 5d/week, 48week/year = £1,881/y
ADDED VALUE COSTS?

16. HOT WATER – ENERGY
The energy needed to heat water is given by:
Energy required (kWh) = V x (T2 – T1)
860
Where V = volume of water heated (in litres)
T1 = temperature of water to be
heated (if unknown, assume 12°C)
T2 = temperature water is heated to (°C)
860 = conversion factor to convert kcal
to kWh (860 kcal/kWh)

17. Hot
water
tank
Water heater
Added value
Water
Maintenance
Energy
Energy
Labour
Chemicals
Maintenance
Energy
Labour
Maintenance
Raw water
tank Softener
Mains
water
Hot (65oC)
softened
water to
supply
107.8p/m3
100 m3 per day
500 W UV light
= 0.8p/m3
1 m3
15 » 65oC
2.9 p/kWh
= 187.3 p/m3
1 m3
Salt and
regen water
= 46.4 p/m3
Value of hot water
= 342.3 p/m3
ADDED VALUE COSTS?
2012/13 tariffs
Northern Ireland Water

18. TRUE VALUE OF WATER
Type Typical cost 1
Mains supply £1.078/m3 (std)
Chlorinated water3 £1.098/m3
Softened water £1.548/m3
Demineralised/Deionised water £3.028/m3
Hot water (65°C) – gas heated2 £3.068/m3
Hot water (65°C) – electrically heated2 £5.868/m3
Steam – gas heated2 £24.888/tonne
Ice (-7oC) £11.358/tonne
1 – approximate, based on 12/13 costs excluding capital costs and renewals and excluding disposal costs
2 – heating 12 to 65oC; energy costs at 2.9p/kWh for gas and 7.0p/kWh electricity and boiler 90% efficient
3 – Simple sodium hypochlorite addition
2012/13 tariffs
Northern Ireland Water

19. SO, WHAT DOES IT COST?
EXERCISE:
Judge the flow and what this running tap
would cost:
3 mm stream = m3/year
Cold water cost = £ /year
Hot water cost (gas) = £ /year
Hot water cost (elec) = £ /year
394
1,107
1,816
2,817

20. SO WHAT DO WE DO?
We’ll go through 12 key actions frequently identified that can improve
water efficiency…..

21. 1 - WATER BALANCE
Get a good understanding of water use on your site by using a water
balance. It’s based on a very simple concept: what goes in must come
out (somewhere). Draw a simple block diagram…
Source: Envirowise GG152

22. KEEP IT SIMPLE !

23. ESTIMATE WATER USE
Use sub-meter data or estimate water use if no data is available:
• ‘Domestic’ component from the number of people on site per day
Staff / delegates 25 – 45 litres/person/day no canteen
50 – 90 litres/person/day canteen
• For plant and process use volumes, rated capacities of equipment/
how long they operate for, etc
• If all fails - bucket and stopwatch!

24. 2 - FIND YOUR MAIN METER !

25. TAKE READINGS !

26. • Locate and check all overflows
• Check for leaks – particularly if
water balance doesn’t balance!
• Remember leaks of raw material or
product – it may cost more than it
looks…
3 – OVERFLOWS AND LEAKS

27. 4 – DISTRIBUTION PRESSURE
• How is your hot and cold
water distributed around
your site?
• Is it off mains supply
pressure, gravity supply or
is it pumped?
• What pressure is the hot
and cold supply operating
at?
• Is the pressure too high?
Water tank
Third floor
Ground floor
Hand washing: 500 uses, 20 sec/use, 260 day/year
Overuse 780 m3/year - £2,968/year
10 litres/min
28 litres/min

28. • Fit a pressure reducing valve or
• Reduce the booster pump
pressure control setting
PRESSURE CONTROL
Do you need 10 bar or will 2 bar (or less) do?

29. PRESSURE – THE SAVINGS
Source: Envirowise GG522

30. 5 - LAGGING
• Lagging – hot or cold it can
save water (and energy!)

31. 6 – TURN IT OFF !
• Once through pump seal
water?
• Does flow stop if the unit is not
working?

32. 7 – PROCESS TANKS
• Does the tank overflow?
• Is the tank difficult to clean?
• Is there any unnecessary water
use?

33. 8 – HOSES
• Diameter of hose – 25mm or 15mm?
• Trigger operated?

34. 9 – CLEANING
Tunnel or tray washers:
• Make sure all nozzles are
present
• Make sure discharge is
visible

35. 10 - CLEANING - CIP
Advantages:
• Water efficient
• Recover cleaning
chemicals
• Repeatability of clean
• Automatic

36. Bottle
washer
Washwater
tank
Mains supply
Overflow
to drain
Hot water from
cooling
Hot water supply
High-level
top up valve
11 - PROCESS CONTROL

37. Bottle
washer
Mains supply
Little overflow
to drain
Hot water from
cooling
Hot water supply
Low-level
top up valve
Water source
controlled
Washwater
tank
Savings: £15,000 p.a
water/effluent/energy
Costs: £2,000
Savings: £5,000 p.a
water/effluent/energy
11 - PROCESS CONTROL

38. 12 - RECOVER AND REUSE
Condensate recovery
• Why not collect it?
• Value around £4.37/m3

39. OTHER WATER SOURCES
• Rainwater harvesting
WATER USE QUALITY REQUIRED TREATMENT OPTIONS
 Nurseries, sports grounds,
gardens
 Toilet flushing
 Cooling (boilers)
 General cleaning
 Filter backwashing
LOW: Water is not used for
consumption, and there is a very low
risk of contact. Water should look
clean and be odour free
 First flush diverted
 Coarse filter
 Laundry
 Cleaning of equipment or
process cleaning
MEDIUM: Water is not used for
consumption, and there is a low risk of
contact. Water must be clean and
odour free, but not necessarily sterile
 All of the above, plus
 Fine filter (possibly
membrane filter)
 Food processing
 Cleaning food processing
equipment
 Substitute potable supply
HIGH: Water may be used for
consumption, water must be clean,
odour free and sterile
 All of the above, plus
 Pathogen removal and/or
inactivation (e.g. UV
treatment)
Source: Envirowise EN896 ‘Reducing mains water use through rainwater harvesting’

40. OTHER WATER SOURCES
• Borehole supply
TYPICAL WATER USE ADVANTAGES DISADVANTAGES
 Nurseries, sports grounds,
gardens
 Toilet flushing
 Cooling (boilers)
 General cleaning
 Filter backwashing
 Low cost supply
 No reliance on third parties
 No licence (up to 20m3/d)
 Reliant on groundwater
availability (quantity and
quality)
 Borehole construction
required
 Laundry
 Cleaning of equipment or
process cleaning
 All of the above, plus
 May need storage
 May need treatment
 Food processing
 Cleaning food processing
equipment
 Substitute potable supply
 All of the above, plus
 May fall under Private Water
Supplies Regulations
(Northern Ireland) 2009
Increasingquality
requirement

41. OTHER WATER SOURCES
Borehole supply also:
• Need to notify NIEA Water Management Unit, Lisburn
• Over 20m3/d will need a licence
• Fees may apply (>20m3/d)
The legislation can be viewed at:
http://www.ni-environment.gov.uk/water/water_resources.htm

42. OTHER BENEFITS
Impact on carbon emissions as:
• greenhouse gas emissions emitted in supply of 1Ml water (1,000 m3)
is 0.34 tonnes CO2 equivalent (= 0.34kg CO2/m3)
• greenhouse gas emissions emitted in treating 1Ml sewage (1,000 m3)
is 0.71 tonnes CO2 equivalent (= 0.71kg CO2/m3)
Adapted from Water UK Sustainability Report 2010/11.

43. The Consumer Council, with the support of Invest NI and NI Water, is
launching “Water Champions”, an award for businesses that have taken
steps to reduce their environmental impact and save money by reducing their
water use. The awards are free to enter and open to all businesses across
Northern Ireland.
OTHER BENEFITS

44. FURTHER ASSISTANCE
If you would like further assistance you may find:
• Invest NI
Maximising efficiencies (inc water) see
• http://www.investni.com/index/already/maximising.htm
Cut water costs information resources (inc on-site reviews)
• http://www.nibusinessinfo.co.uk/content/cut-water-costs
• NI Water
• http://www.niwater.com/waterefficiencybusiness.asp
• WRAP
• http://www.wrap.org.uk/
• Enhanced Capital Allowance (ECA) scheme
• http://www.nibusinessinfo.co.uk/content/first-year-allowances-water-efficient-
technologies

45. QUESTIONS,
ANSWERS
AND DISCUSSION