Richard Heinberg, an American journalist, argues that in building the renewable energy infrastructure to stop global warming, we are actually involved in one of the greatest change projects in human history. In addition to solar panels and wind turbines, we have to build an alternative transport infrastructure, farming procedures and industrial processes. This transformation cannot happen without fossil fuels. For instance, production of concrete structures and steel elements require amounts of energy that is only possible to produce with fossil energy. Production of solar panels requires scarce and expensive minerals which must be excavated, again requiring the use of fossil fuels. Thus, the harder we push towards a renewable energy system, the faster we have to use fossil energy for the construction process. This is not only expensive, but also an undermining factor for our efforts to cut global emissions. Heinberg remarks that the cost of building this new energy infrastructure is seldom counted in transition proposals, which tend to focus just on energy supply requirements.