More and more hotels are going green - even a two-and-a-half pearl Holiday Inn could have some kind of green measures in place. (In fact, the company uses a centralized "Green Engage" program that allows its properties to customize environmental measures to meet certain requirements.) Read on for six signs that your hotel is environmentally friendly, whether it's a glance in bed you're sleeping or the key that allows you in the room.

A sustainable structure

Let's start with the very first thing you'll encounter in a hotel - the building itself. Today, many new buildings are seeking LEED certification, which proves that the building itself is green. Located in Teton Village, Wyoming, and in harmony with its beautiful natural environment, Hotel Terra is one of a handful of hotels that are implementing green practices with its surroundings. Its structure is made of recycled materials, so that a minimum of new material is used in its construction. The rest of the infrastructure is further improved: the LEED-certified hotel uses solar, wind and hydroelectric power.

Local furniture

Shipping enough furniture for a hotel across a country or continent can lead to significant CO2 production, which is why some hotels source locally. One of the leaders in environmentally friendly hotels, the 1 Hotel brand, buys its furniture - largely made of recycled wood - from craftsmen in the region in which it is located. 1 Hotels also has other original green touches: Central Park location, guests will have cardboard hangars instead of plastic, do not disturb the stones instead of paper panels, and hourglasses five minutes away in the shower.

Produce grown on site

If your product tastes particularly fresh, you may be lucky enough to stay in a farm to hotel restaurant, where food is grown fresh in a vegetable garden on the property. And it's not just in country hotels: you'll find an organic herb garden, created in 2008, at Fairmont Singapore, in the heart of the vibrant central business district. Crosby Street Hotel, located in Soho, New York, has a rooftop garden that grows everything from melon to tomato, a few minutes’ drive from the hotel kitchen.

Electricity that only works when you are in the room

One of the most common ways to save energy - especially on properties outside the United States - is to limit its use when you are in the room. Some hotel room air conditioning units and lights only turn on when your key is in a small special pocket near the door. Remove it when you leave, and the part goes into power-saving mode until you - and the key - are back. They are not only luxury hotels, either: three-pearl chains like the Best Western in Europe have key locations.

Eco-educational programming for guests

Although not necessarily an eco-responsible term, more and more hotels focused on sustainable development are also educating their guests about wildlife and surrounding conservation efforts. Six Senses Ninh Van Bay in Vietnam; for example, teaches guests about marine life as part of its efforts to protect a coral reef near the property. He also collects food from his organic garden, employs the residents first and gives back to the community by providing purified water to the residents.

Renewable energy sources

Renewable energy is one of the most obvious, but effective ways to contribute to a hotel's eco-friendliness, and many hotels, especially in sunny destinations where solar panels are a logical choice, are moving in this direction. But some of them are really improving the game. For example, the ultra-luxury Brando in French Polynesia is about to be completely carbon neutral, thanks to its 100% renewable energy plan that uses the sun and coconut oil biofuel to power the property. Another local element - seawater - powers the air conditioning, while rainwater collected on the roof is used for toilets and laundry. In Japan, the Hoshinoya Karuizawa uses the nearby river for hydropower, which supplies 70% of its energy, including under-floor heating.