Paper: Water Consumption Benchmarks – a step towards reduced consumption By the Malta Business Bureau’s EU LIFE+ Investing in Water Project st
Presented at the Chamber of Engineers Annual Engineering Conference..... Water: A 21 Century th
Challenge, 9 May 2012
Author:
Ing. Marco Cremona, Water Expert to the EU LIFE+ Investing in Water Project
Co-Author:
Geoffrey Saliba, Project Manager to the EU LIFE+ Investing in Water Project
Abstract 3
With only around 40m of renewable freshwater per capita, Malta is considered one of the top ten countries worldwide for water scarcity. Malta’s only natural exploitable source of freshwater is groundwater, yet 48% more of this resource is estimated to be extracted than is naturally recharged on an annual basis. It is critical that wasteful consumption is eliminated if this unsustainable overexploitation is to be stopped. The Malta Business Bureau’s EU LIFE+ Investing in Water Project is an EU funded project aimed at identifying water-saving solutions for businesses and hotels, thus leading to a reduction in water consumption of at least 10% amongst interested enterprises. The project is managed by the Malta Business Bureau, supported by partners The Malta Chamber of Commerce, Enterprise and Industry, and the Malta Hotels and Restaurants Association. The project, which started in October 2011 and will run until March 2014, is the first national initiative of this scale addressing the sustainable use of water in Malta to be carried out by a local partnership.
This paper presents water consumption benchmarks for several industries and hotels of different classifications as obtained by the Project at the time of writing (May 2012). These benchmarks may provide an accessible reference point for plant engineers, managers, engineering services consultants and officials entrusted with cost-cutting to compare their water consumption. The benchmarks may also serve to identify the consumers’ need to more efficiently manage their water consumption, thus guiding water conservation efforts.
Introducing the EU LIFE+ Investing in Water Project
The project aims to empower enterprises and bring them to a position where they can analyse their consumption, identify appropriate solutions, then implement the solutions and monitor consumption to evaluate the success of the interventions.
The EU LIFE+ Investing in Water Project advocates the following water saving hierarchy: 1) Reduce waste by increasing the efficiency in consumption; 2) Harvest and use rainwater; 3) Carry out the in-house recycling of waste water (grey or black) for re-use; 4) Source externally recycled waste water for use (e.g. using treated effluent from municipal sewage treatment plants). This paper supports the project’s aim of helping enterprises reduce their consumption by presenting current water consumption benchmarks for 3,4,5 star hotels, offices, and manufacturing enterprises, together with a general breakdown showing the percentage range of service water compared to process water consumed by these enterprises.
The paper also identifies a water-saving opportunity which was revealed through a set of water audits carried out by the project. The opportunity arises from the lack of standardisation in flow rates of showers and wash hand basins, and toilet flushing volumes which leads to excessive water consumption in these facilities. Through this paper the project is recommending standard flow rates and flushing volumes, which will help enterprises in their efforts to reduce service water consumption. Empowering enterprises to save water – the process
There are three main actions forming part of this process. Through data audits and on-site audits the project is analysing enterprises’ consumption and recommending appropriate water-saving solutions. These audits are taking place in two waves – the first started in January 2012 being concluded by May 2012, the second starting in November 2012 carrying on through December 2013. During this second wave of water audits the project will also offer ongoing consultation through individual meetings and technical group workshops. Representatives from enterprises can attend these workshops during which the different water-saving solutions will be detailed.
Importantly, prior to the second set of water audits the project will publish a detailed single reference document through which enterprises will be given a self-assessment tool allowing them to analyse their water consumption and identify water-saving solutions applicable in their circumstances. The document will then detail the various water-saving solutions. This Water-Saving Solutions Pack will be published in the third quarter of 2012, following which it will be distributed to businesses and hotels in Malta, and made publicly available through the project website – www.investinginwater.org
Throughout this process the project will also monitor enterprises water consumption to evaluate success of adopted water saving solutions. Trends in water consumption – results of the first set of water audits
The Project has carried out 39 audits to date, in 19 hotels and 20 businesses. The hotels ranged from 3 star to 5 star, while the businesses surveyed ranged from offices employing 30 staff to 1
manufacturing facilities with 950 employees . It was decided at the onset that the project would try to engage a wide and varied range of businesses as possible, also so that the solutions arising thereof could be employed across the board. Although the project’s focus is on service water (i.e. water used by guests in the guest rooms in the case of hotels, and employees in the case of businesses), the water expert engaged by the project to carry out the audit also evaluated process water use and provided recommendations on how it is possible to save process water too.
Water consumption data for 2011 (on a month by month basis) was obtained from the various businesses and assessed by the project. In the case of hotels this data was generally readily 1
Numbers rounded to the nearest 10.
available; in the case of some businesses the only water data made available were the water utility’s bills, usually issued every 2 months. In most instances, town water was not the only water used in the premises, with some hotels and businesses purchasing bowser water (potable or non-potable), others abstracting groundwater through registered boreholes, and some others still using seawater for the flushing of toilet cisterns. Rainwater harvesting is practiced in some instances, albeit to a small degree. Most large coastal hotels produce their own water in-house by means of their own desalination (Reverse Osmosis) plant. While Reverse Osmosis plant production is metered, other sources are generally not, necessitating the use of realistic assumptions in order to derive a complete picture of consumption.
Correlations were derived between guest nights and water consumption, also as a means of verification of the data supplied by hotels. This is important because hotel occupancy varies considerably between the peak (summer) and low (winter) seasons, with variations of 40% to 100% being recorded.
In the case of office buildings, water consumption is relatively stable and only varies seasonally through the additional employment of some part-time staff in summer.
The data collection enabled the Project to produce the first consumption benchmarks for Malta which are based on such in-depth data analysis of water consumption.
The results are shown in Figure 1 below.
Current Benchmarks: Hotels 3* – 199 lt per g/n Hotels 4* – 292 lt per g/n Hotels 5* – 462 lt per g/n Offices – 25 lt per e/d Factories – 24 lt per e/d Factories w/showers – 46 lt per e/d Figure 1: Current Consumption Quantities for hotels and businesses in Malta
The project also sought to construct a breakdown for the water consumption of each audited hotel and business. Figure 2 shows examples of typical water consumption patterns for a hostel-type hotel and a 5 star hotel.
While the service water (water used in showers/baths, wash-hand basins and toilets) consumption in a hostel-type hotel makes up for as much as 85% of total consumption, this drops to around 40% in
the case of some 5 star hotels – the reason being that 5 star hotels have a plethora of non-guest related water consuming services such as swimming pools and spas, landscaping, conference and wedding halls, laundries, restaurants and cafes catering for non-guests etc.
Figure 2: Breakdown of water consumption for different hotel categories
Similarly there are significant differences in the way water is used in businesses. Whereas the water consumption in office buildings is almost exclusively service water, manufacturing facilities may consume significant amounts of process water (Figure 3). While the amount of process water consumed depends greatly on the product being manufactured and the manufacturing process, it is not uncommon for the service water consumption in manufacturing facilities to exceed the process water consumption.
Figure 3: Breakdown of water consumption for an office building and a manufacturing facility
The first set of audits showed that service water (toilets, showers, wash-hand basins) could account for: -
Between 38% and 86% of total water consumed by hotels
-
Between 5% and 98% of total water consumed by offices and factories
Water-saving opportunity – adopting standard flow rates and flushing volumes
Over the course of the audits the project took measurements of actual flows from taps and showers, and noted flushing cistern volumes for toilets. Huge variations in flow rates were observed, not only
from one premises to another but also within the same premises. This is attributed to systems which result in water pressure varying from one floor to another and is more pronounced in multi-storey buildings (generally hotels) with the water pressure, and subsequent flow rates, being higher in the lower floors. In some instances, a gravity fed (roof tank) water system may be delivering an insufficient 4 litres per minute from a shower head at the 5
th
floor level, while also delivering an
st
excessive 12 litres per minute at the 1 floor level.
It was also noted that toilets having a wide range of flushing volumes are installed in hotels and businesses in Malta, with a flush volume of anything from 6 litres to 15 litres having been encountered over the course of the audits.
The project concludes that in general, most systems have an element of over-design which is resulting in more water delivered for service water features than necessary.
For this reason and on the basis of the experience gained through the audits, the Project recommends that enterprises adopt the following flow rates and flushing volumes as standards:
Toilet flushing cistern volume
– 6 litres
Shower flow rate
– 7 litres/min
Wash-hand Basin flow rate
– 5 litres/min
From the data obtained so far, the Project estimates that through the adoption of these standards, savings of 10% - 15% on service water can be achieved.
The near future
Until the end of 2013 the project will continue working with enterprises to facilitate the adoption of water saving solutions. The project will also monitor water consumption to evaluate the success of these solutions in reducing water consumption.
The project therefore foresees that during the first quarter of 2014 a follow up to this paper will be published, announcing updated water consumption benchmarks for enterprises which have successfully adopted water saving solutions.
ENDS
For further information please contact: Geoffrey Saliba Project Manager EU LIFE+ Investing in Water Project Malta Business Bureau, Casa Leone, Pjazza Robert Samut, Floriana, Malta Tel: +356 21 251 719 | E-mail: gsaliba@mbb.org.mt Website: www.investinginwater.org - www.mbb.org.mt
The Malta Business Bureau thanks the EU LIFE+ Investing in Water Project partners the Malta Chamber of Commerce, Enterprise and Industry and the Malta Hotels and Restaurants Association for the support provided in carrying out meetings and water audits amongst enterprises. It also thanks the Ministry for Tourism, the Environment and Culture, EasyDry Malta, APS Bank, Island Hotels Group, MSV Life for their financial support without which it would not have been possible to carry out the project.
In addition, all the participating enterprises receive a special note of appreciation for collaborating with the project.
Recommended citation:
EU LIFE+ Investing in Water Project, Water Consumption Benchmarks May 2012; Cremona, M Saliba, G.
Project partners:
Project co-financiers and sponsors:
Ministry for Tourism, Culture and the Environment