Talking Point: Four Ways Hotels Can Recover and Re-use Waste Energy

Are you sending energy down the drain?

Are you sending energy down the drain?

You may be doing everything you can to be energy efficient, but more than half of energy produced is wasted. Did you know it’s possible to recover waste energy and re-use it? José Melico, Founder of Zypho explains how.

Hotels around the world are investing in reducing their energy consumption by using more energy efficient technology and methods, and encouraging guests to adopt eco-friendly habits such as towel reuse.

But, despite individual and commercial efforts to reduce energy consumption and become more efficient, more than half of energy produced in the UK is still being wasted, at an overall cost of £9.5bn per year. In order to truly address energy consumption, the future is in the recovery of inevitable waste energy from everyday functions, and finding ways to reuse it to further reduce energy consumption.

So how can hotels recover energy wasted in their day to day processes? Here are some examples of established and developing energy recovery technology being adopted in hotels and the hospitality industry.

Biogas from Biomass Waste

Food waste can of course be recycled, with many owners composting food to use around hotel grounds and to fertilise hotel grown produce, but energy from food waste can also be extracted and recovered by hoteliers. The Savoy Hotel, London uses biomass broken down by anaerobic digestion (AD), which is gathered with other commercial food waste and converted into biogas for electricity at the PDM power plant, with the electricity then supplied to the grid. AD waste can also be converted to heat energy, and the technology is widely available. Walt Disney World has its own biogas facility built by Harvest Power clean tech company.

Drain Water Heat Recovery

Valuable energy in hotels is literally going down the drain with every shower taken. The process of temperature regulation is inefficient: The cold water comes directly from the mains as the hot water comes from a heating device. During the shower, the shower tap mixes a large volume of hot water to the cold water to obtain the ideal water temperature for the user. A water heat recovery device installed under a shower tray or a bathtub can recover energy from the warm water heading down the drain. The heat is transferred to the cold water mains before arriving to the shower tap mixer. The cold water reaches the mixer tap already preheated, thus requiring less hot water to reach the ideal temperature.

The 85-bedroom Premier Inn in Douglas, Isle of Man uses Zypho waste water heat recovery devices to reduce the cost of energy for heating water for room showers. It is a passive technology and competitively priced solution that allows them to achieve SAP energy assessment.  A hotel of this size uses on average, 20,000 kWh per month for heating shower water. With the waste water heat recovery technology installed in every room they can potentially save 1/3 of the energy demand for every shower.

Heat Pipe Technology

Hotel heating and air conditioning systems are a huge source of energy waste due to this process being enacted on a large scale and variable from room to room. Heat pipes are thermal transfer devices capable of transferring heat and energy several hundred times faster than conventional methods.  Using the technology can recover up to 70% of the heat energy. There are many types of heat pipe devices, and all are designed to be compact and require minimal intervention.

For an example of heat pipe recovery in action in a hotel setting, Advanced Cooling Technologies (ACT) provides a testimonial of their heat pipe system, created for a Korean resort hotel to recover waste heat generated by the air conditioning. The hotel is located in a major metropolitan area, with an estimated cost of electricity at $0.15/kWh. At the design point, energy recovery savings are approximately $104.40/day.

Steam Energy Recovery

Steam has played a huge role in energy production since the industrial revolution, and now energy recovery from steam produced in hotel kitchens is becoming more widespread in hotels and restaurants. SMEG Foodservice is one example of a steam recovery system being used in hotel dishwashers. Steam forming in the washing chamber flows into the steam recovery unit placed at the back of the dishwasher. A ventilator pushes it into contact with water pre-loaded in the machine and circulated through an auxiliary hydraulic pump. The water comes down as rain, heating as it comes into contact with the steam below, with up to 30% energy savings.

Energy recovery technology is attracting an increasing amount of investment and the global energy recovery devices market is estimated to witness a considerable growth for the forecast period 2015 to 2025. There is ample opportunity for hotels to harness established and emerging technology, helping them meet their sustainable development goals and move closer to eradicating waste energy from operations.

 

Jose Melico founder of Zypho

Jose Melico founder of Zypho

About Zypho

Zypho is a water heat recovery device that reduces shower water heating energy bills by up to 30 per cent and improves energy efficiency.

It is installed under a shower tray or a bathtub, becoming part of the drainage system and allowing around 10°C of shower water that passes through the device to be recovered. The recovered heat is then transferred to the cold-water mains before arriving at the shower tap mixer already preheated, meaning less hot water is required to reach the optimum shower temperature.

Zypho has gained international performance and compliance certifications in 10 different countries and its technology is compatible with shower systems around the world. 10,000 Zypho units are already installed in 15 countries (including the UK) across 4 continents, and the technology is patented internationally.

Leave a Reply