Greywater Harvesting for Hotels
From Green Hotelier: http://www.greenhotelier.org/
Water stewardship is an extremely important aspect of good environmental practice for hotels. Many use reduced flow and flush in bathrooms, but how many are recycling water?
Water re-use is becoming core to many companies’ sustainability efforts and it’s never been more important. Freshwater withdrawals have increased globally by about 1% per year since the 1980s (UN, 2016) and it is estimated that water scarcity now affects 40% of the global population (CAWMA, 2007). Even in the UK some areas are reporting difficulties in meeting demand.
Hotels often do a lot to manage water consumption. Low flow taps and showers or aerators, reduced flush toilets or no flush urinals, sensor activation and good housekeeping practices all help to reduce the amount of water per guest, per room and per stay. But, even with these measures many guests admit to using much water during a hotel stay than they would at home, and in some water scarce areas, the difference in consumption between a hotel guest and the local population can be up to 20 times and dozens of litres.
Anything hotels can do to better manage their water consumption is a good thing, but how many look at recycling water?
Significant water consumption savings can be made from re-use initiatives. Rainwater harvesting can reduce mains water consumption by up to 30% whereas greywater recycling can save as much as 40%. Aside from lower metered water bills, companies can also benefit from reduced risks of storm water flooding, decreased sewerage charges and lower energy costs associated with water supply.
New water re-use solutions offer commercial organisations a variety of cost-efficient, reliable and highly effective options to help achieve their sustainability goals. Claire Yeates, a Director at Waterscan said: “Many companies are aware of the benefits of water re-use but are naturally concerned about payback times and the potential operational impacts of installing new technologies. Add to this reliability issues from early-to-market systems and it’s easy to see why widescale uptake of water recycling has been hindered. We firmly believe that greywater recycling and rainwater harvesting can play a significant role in many company’s water strategies and that is why we are bringing new best-in-class technology to market.”
The various water recycling systems have been developed to give greater system design flexibility in line with customer priorities and requirements, plus a 30% faster return on investment. Waterscan systems now feature:
- Multiple tiered redundancy to ensure complete integrity of supply.
- Built-in telemetry which transmits system data and live diagnostics for preventative maintenance.
- Siemens smart user interface for usage data and enhanced system monitoring.
- Variable speed, load sharing pumps, insulation and slow close valves for an even quieter operation.
- Low energy components so the system can produce 1m3 using just 1.5Kw/h energy.
- A smaller system footprint which reduces installation costs and impact on building footprint.
Barry Millar, Operations Director at Waterscan, said, “Our new water re-use systems are now designed and largely built in the UK using modular components. This enables us to meet clients’ exact specifications in line with individual business strategies and site requirements. Our complete service involving design, supply installation and maintenance of water-saving systems, along with our consultative approach, gives us a unique ability to deliver optimum results across varied client property portfolios. All of this means that our clients will benefit from a faster return on investment and still have complete confidence in their operations.”
Greywater Recycling in Action at Premier Inn
In partnership with its client Premier Inn, Waterscan installed a greywater recycling system in water-scarce Abu Dhabi. The initiative is vastly reducing mains water consumption, saving an average of 735,000 litres (24%) of mains water each month – 60 litres per guest. Over the course of a year, this is the equivalent of 110,000 baths. 100% of toilet flushing at the hotel now uses recycled water.
Greywater recycling captures the water used for showering or bathing and, after treatment through an ultra-filtration membrane system, is fed back into the property for non-potable purposes such as flushing toilets, irrigation and laundry.
- Greywater Recycling Batch System: where low energy consumption is a priority and there is physical space for a larger system footprint, this low pressure filtration method takes a little longer but uses less energy in the process.
- Greywater Recycling On-Demand System: where space saving and a faster return on investment are priorities, this high pressure approach delivers rapid ultrafiltration and therefore requires less tank storage and correspondingly reduced installation costs.
Rainwater is collected, filtered and fed back into the property through a robust treatment system ensuring that only the cleanest water is utilised for non-potable purposes like vehicle washing, toilet flushing and irrigation. A rainwater harvesting system is suitable for all commercial applications where there is adequate roof space to harvest sufficient water to achieve a good return on investment.
ITP members are acting on water on behalf of the industry by collaborating with member hotel groups to develop the Hotel Water Measurement Initiative. This universally recognised tool and metric will help all hotels of any size, anywhere in the world measure in a consistent manner. The HWMI is currently in the testing phase and will be released as a free tool for the industry in World Water Week at the end of August 2016.