Plastics are petrochemicals, or so it's believed by the public, the media, the governments and the industries themselves. But so are glass, paper, metals, etc., because energy is needed to get them into usable form. More fuel is consumed in the trip from crude oil to polymer than the fuel value of that amount of oil. For example, a gram of petroleum will yield around 42 kJ of energy if burned at 100% efficiency (we get much less in current furnaces) but it takes about 85-170 kJ to make a gram of plastic (PVC is lowest/best - hear that, Greenpeace? ). Even if we start from bio-based products like corn, we must add in the fuel needed to grow and process that product, including plowing, planting, fertilizers, water supply, harvesting, disposing of waste (cornstalks), and the physical and chemical processes needed to convert it into a pymer. So are bio-plastics really good for the environment? It depends ... on numbers no-one is publicizingol, and maybe not even calculating.The workshop can be used to fix things to avoid new purchase, or to follow a hobby.