Around the world, traveling by train is an incredibly popular form of transport. At its best, taking the train can be a scenic, relaxing and gentle way to travel, and many millions of people rely on the railways to get them to and from work every single day.
In Italy, one business is looking to develop a more sustainable version of a piece of infrastructure that is crucial to the smooth running of railways.
Milan-headquartered Greenrail has developed technology which enables the manufacture of railway sleepers from "secondary raw materials."
"Greenrail sleepers are railway sleepers that have the same mechanical characteristics as traditional, reinforced concrete sleepers, which represents the standard in the current market," Giovanni de Lisi, the company's CEO, told CNBC's "Sustainable Energy".
"They're mainly made of recycled plastic: urban plastic and old recycled tires," De Lisi added. He went on to state that every kilometer of railway line made by Greenrail allowed the recycling of 35 tons of plastic and used tires.
The business also says that a Greenail sleeper can incorporate photovoltaic panels to enable solar energy harvesting. "The idea of the Greenrail Solar was borne from the will to transform the railway infrastructures from passive infrastructures to active infrastructures," de Lisi added.
"The railway tracks are exposed to the sun 90 percent of the time — from here comes the idea to collect solar energy and transform it into electricity," he added.
Greenrail's COO, Firas Bunni, told CNBC that for every one kilometer of the solar sleepers, an estimated 30 to 35 megawatt hours per year of energy could be produced, enough to meet the average needs of 10 Italian homes annually.