In many hotels, domestic water tanks waste energy by heating water 24 hours a day that is only used for 12 to 16 hours. Temperatures are also usually too high - often ranging from 140 F to 170 F (60 to 75C).Except for dishwashing and certain loads of laundry, tap water at 130F (55C) is adequate; above that temperature people have to add cold water to avoid being scalded. Finally, many hot water systems are not working at full efficiency, which leads to a considerable loss of energy.
Establish a standard temperature setting of 130F for all hot water tanks. It is recommended that setting your hot water temperature at 130F for two reasons; first, guests will need a maximum temperature of 120F (49C) for comfort. Secondly, heating water to 130F eliminates the risk of Legionnaires' disease, as the legionellae bacteria can only grow in stagnant water at temperatures from 68F to 122F (20C to 50C).
Reduce hot water waste through maintenance
Initiate a schedule of regular maintenance of all aspects of your hot water systems. If the system is working efficiently, you will waste less energy.
Your maintenance routine should include the following tasks:
Ensure that all major hot water pipes and storage tanks are fully insulated and check the insulation regularly.
Drain and flush your hot water tanks at least every six months to prevent scale build-up and deposits, which can reduce heating efficiency. Remove exterior scale build-up and build-up on electric hot water heater coils at least annually. With immersion type hot water heaters installed inside the boiler shell, remove and clean scale from interior and external coil surfaces.
Have all gas and oil burners serviced regularly.
Check all hot water thermostats frequently - setting temperatures is pointless if the thermostats are constantly malfunctioning.
Clean and re-condition hot water temperature mixing valves at least annually.
Save water in the kitchen
Kitchens need hot water for health reasons; however there are many ways to cut back on energy use without compromising safety:
Reduce dishwater temperatures to the lowest temperatures allowed by health regulations and check rinse water regularly for excessive temperature.
Position hot water boosters within five feet (1.5 m) of dishwashers, insulating the pipes and shutting off boosters when not needed.
Turn on the dishwasher only when it is fully loaded; it uses the same amount of energy and hot water whether it is full or empty.
Turn the water heater down to 75F (24C) when the kitchen closes; turn it back up two hours before opening your particular unit to allow for appropriate warm up time.
Install point-of-use hot water heaters for public washrooms
Compact, self contained point-of-use (or point-of-demand) instant electric water heaters eliminate the heat loss from storage tanks or lengthy hot water supply lines.
They can be mounted directly or below the basin or tub and are ideal where the demand for hot water is light, for example, when people are merely washing their hands.
Heat and pre-heat water with solar energy
Solar energy is a long established and well-proven method of heating water, especially in areas that enjoy regular sunshine. In the hospitality industry, solar water heaters are commonly used for heating swimming pools and for preheating water for other uses. Water preheated by solar energy uses less of other forms of energy to raise the temperature to the desired levels. Generally the cost of installing solar heating is recovered in four to five years - after that, "free" hot water is supplied with minimum maintenance.
Always wash in cold water wherever possible
In the laundry, all clothes and linens should be washed in the coolest water that will do the job to the required level. Check with your supplier of laundry equipment to see what is the most current and efficient technology.
Alternatively, install a system to recover heat from laundry wastewater to preheat the incoming water. This reduces the cost of water heating - the system should pay for itself and start saving you money in fewer than three years.
Alka Patel is director of communications at Fairmont Dubai Hotel. Contact: firstname.lastname@example.org.For all the latest travel news from the UAE and Gulf countries, follow us on Twitter and Linkedin, like us on Facebook and subscribe to our YouTube page, which is updated daily.
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