Cutting energy and carbon use in hotels
This post looks at hotels, how they use energy and what the industry is doing to cut energy use and emissions.
The hospitality industry is big. Globally, it generates revenue of over $500 billion and is a huge employer of permanent and temporary staff. Hotels are often located in areas of natural beauty and have an impact on their local environment.
It takes a lot of energy to run a hotel.
The largest use is normally electricity. Gas is used for cooking and then diesel for backup generators.
The energy intensity of hotels varies around the globe, as different seasonal weather profiles require different cooling needs. In summary, however, a hotel that uses between 200 – 300 kWh/m2 appears to be doing well, while the norm for one that is average or poor is over 500-600 kWh/m2.
Architecturally, hotels bring together three very different types of spaces:
- Guest rooms: Guests stay in bedrooms, with attached bathrooms and often large expanses of windows. They can control the temperature and lighting in their rooms and use small appliances provided by the hotel or that they bring with them.
- Common areas: These include the reception, lounges, meeting rooms, swimming pools, gyms, saunas and similar areas. They are usually large spaces and lose energy to the environment around them.
- Service areas: These areas such as kitchens, laundries and offices where there is equipment, specialist air handling and ventilation equipment and computers and office equipment.
This means that you have more options in each area to reduce energy usage and the challenge is to select a mix of measures that you can implement within the constraints of the hotel.
Energy costs may be insignificant – but still large
In a typical hotel, the costs of energy may be only 4-6% of the operating costs. It might be a much smaller fraction of overall revenue.
But it can still be the second largest operating cost – and a line item where any saving goes straight to the bottom line.
How can you start to understand how your hotel uses energy?
Hotels, like most organisations, focus on energy costs on the bill. The problem is that knowing how much energy you use in total is of little use when trying to work out where you use it in the hotel itself.
This is because there is rarely any metering that is in place apart from the main billing meter.
There are, however, studies that shows how energy typically is used in hotels. For example, lighting can be 12-20% of the total load. Domestic hot water can use up to 15%. If there are chillers that are metered, the cooling energy requirements can be worked out quite accurately.
Let’s say you have all this data – then what?
Research suggests that most hotels are actually quite poor at managing energy efficiency over time. They are most efficient when initially commissioned, and do well after a major retrofit. Over time, however, performance starts to fall, which is inevitable without some kind of management system in place.
The other thing is that the largest driver of hotel energy consumption is something that you have little control over – the weather. Electricity consumption in particular correlates well with outside air temperature.
So, what does that leave you with as an option to control? Well there are the guest rooms and common areas where you could control temperatures. But you have customers there – and keeping them comfortable is much more important than saving a little bit on energy costs.
Where hotels are doing their bit is using labels to try and get their customers to help them save energy, for example by putting labels in bathrooms asking people to reuse towels if they can.
How do you tell how well a hotel is performing?
Enter what seems like a seriously cool online hotel footprinting tool.
The image below is a screenshot of the tool for the UK. It reports metrics based on 6 key measures:
- HCMI Rooms Footprint Per Occupied Room (kgCO2e)
- Hotel Carbon Footprint Per Room (kgCO2e)
- Hotel Energy Usage Per Occupied Room (kWh)
- Hotel Energy Usage Per Square Meter (kWh)
- Hotel Energy Usage Per Square Foot (kWh)
- HCMI Meetings Footprint Per SQM-HR (kgCO2e)
That’s a fair number of metrics.
From a combination of studies over the last 20 years, it seems that energy usage per square meter close to 200 kWh/m2 represents a very efficient hotel.
400 – 500 kWh/m2 is the mid-range performance while 600 kWh/m2 and above is an inefficient hotel or one with very high energy requirements resulting from the kit is has in the building or the climate in the area where it was built.
Measuring the energy used in hotels
The hospitality industry spends over $7billion on energy every year. So it’s worth putting in place systems to measure and manage this cost.
The resources for HCMI can be downloaded here http://tourismpartnership.org/resources/.
Another method of measurement is the EarthCheck Certified program, which appears popular in Australia.
Technology in hotels
Energy use could be cut dramatically by introducing new technology into hotels.
For example, Zen Technologies is offering technologies such as smart thermostats, motor controls, LED lighting and ozone water treatments.
Zen claim that there are savings of 30-40% of utility costs based on such technology.
Other technologies include:
- Laundry units that use less water
- Low power Organic LED (OLED) TVs
- Keycard activated lighting
- Touchpad controls
- Software to schedule shifts more efficiently
LED lights can deliver savings of between 50 – 80% according to providers.
On the generation side, you have solutions like an industrial fuel cell at the Radisson Blu in Germany. Supported by Germany’s Federal Ministry of Transport and Digital Infrastructure through a programme called the “National Hydrogen and Fuel Cell Technology Innovation Program”, the fuel cell will supply 3 GWh of electricity and 2 GWh of heat, removing the need for energy from the power grid for the hotel.
Taking action to cut energy and carbon
The tourism partnership has a useful guide on how hotels can go green.
The main areas to focus on are energy use, water use and waste.
This snapshot from the guide is a useful summary.
The areas where you can look to achieve savings include:
- Hot Water
- Air conditioning
- Kitchen equipment
- Laundry equipment
- Swimming pools
- Building envelope
Typically the energy required to condition spaces, heating or cooling large areas is the largest energy consuming activity, followed by domestic hot water. A rough breakdown could be as follows:
- Space conditioning: 70-75%
- Domestic hot water: 15%
- Lighting: 12-18% and up to 40%
- Catering: 15%
Lot cost / no cost tips from providers include turning down temperatures, installing energy efficient appliances, defrosting and cleaning behind fridges and freezers, using low energy lightbulbs, and having occupancy sensors.
It is also important to make sure that building energy management systems are commissioned correctly and are responding in the right way to sensors and settings. It is surprising how often systems are heating and cooling the same space at the same time.
In a best practice guide from Hotel Energy Solutions, the authors suggest an order in which to approach how to integrate energy efficiency in hotels:
- Evaluation: assess where you are and benchmark
- Organisation and behavioural solutions: involve staff and guests for long term change, with information leaflets and training.
- Technical solutions: These include reducing the energy needs through modifying the building, installing more efficient equipment and moving to renewables
These are 18 hotel case studies in this document and they provide useful tips and ideas to anyone looking at the options for energy efficiency measures in a particular hotel.
What can you achieve in practice?
The Ritz-Carlton saved over $11 million in energy costs and reduced energy consumption by 13% over three years. They did this by assessing 32 North American hotels, identifying 790 energy conservation measures (ECMs) and implementing 433.
Hotel Rafayel, a 5 star hotel in Battersea saved over £18,000 by installing LEDs and refrigeration control devices.
In India, the Godrej Bhavan office building invested $99,000 in energy efficiency retrofits, reducing energy use by over 11% the following year.
One aspect of this case study that should be followed by more business case modellers is that the team at Godrej modelled paybacks based on three scenarios:
- 4.7 years under an actual bill scenario
- 8.9 years under a fixed tariff scenario
- 9.6 years under an escalating tariff scenario
This approach gives you a greater insight into possible outcomes and what happens when you spend money on energy efficiency measures – helping you spend money wisely.
In 2011, this building became the first one in Mumbai to achieve LEED gold certification.
In North Carolina, the Proximity hotel spent less than $7,000 on sustainability improvements during construction but saved $2,000 a month just through HVAC system monitoring controls. A detailed case study for this hotel is included here.
The hospitality industry uses a lot of energy but also has a lot of options when it comes to reducing the amount of energy it uses.
Unlike some other businesses, the way in which customers behave has a huge impact on hotel energy use.
You need to do things to Influence and motivate customers to make the right choices, such as reusing towels and turning lights off. You also need to make it easier for them to understand and control temperatures.
The hotel industry is also making efforts to make it easier for hotels to benchmark where they are and what they can do to make a difference.
And, according to the Carbon Trust, hotels could cut costs by 20% quite easily at little cost. So why wouldn’t you look at this if you aren’t doing so already?
Also, you might want to check out the UK’s first hotel energy conference, organised by Vilnis Vesma and the hospitality industry.