>>276030780
Well from their source:
>Glass is made by melting sand and other minerals at very high temperatures. The molten mixture is then cooled to form glass. The most energy-intensive part of the glass-making process is the heat necessary to melt the mineral mixture.1 Because recycled glass still needs to be re-melted to make new glass products, the energy savings from recycling glass are relatively small – roughly 10-15%.
What source did you see that said the opposite?