Hotels in Denver will switch to wooden room key cards during the Democratic National Convention, trying out the biodegradable cards made by Sustainable Cards.

The company makes two types of key cards. One type, which will be used during the DNC, is made of birch wood, a paper-based core, glue and a magnetic stripe. The company's other hybrid card, has a bio-based laminate over the wood. Sustainable Cards is donating 70,000 key cards to hotels for use during the DNC.

Both cards are biodegradable in landfills, according to the company, though the hybrid cards takes longer to degrade than the wood-only ones. The wood used in the cards is harvested though forests certified under the Programme for the Endorsement of Forest Certification schemes.

Although no hotels in the U.S. are exclusively using the wood cards, the company is working with several hotels that are testing them out and will provide cards for the American Hospital Association meeting in September and the International Hotel Conference in Rome in October.

The DNC will also host an exhibit of ideas and projects focused on climate change. The Rhode Island School of Design's "Partly Sunny: Designs to Change the Forecast" display will showcase more than 30 designs related to buildings, food, energy, cities, water and transportation.

The exhibit's central meeting and activity area will house a reconfigurable table made from used shipping pallets. The table, which can seat more than 40 people when set up in certain ways, was designed for the event by Rhode Island School of Design student Kallie Weinkle.