We’ve all heard of big companies pledging to go 100% renewable, including the famous RE100, which cumulates over 100 companies at the moment. The trend of not only making this promise, but starting to effectively take action, has reached its next level – cities.
The newest hot thing about green cities is precisely this commitment to get to 100% renewable energy (usually by ~2050). Criticism and controversy were quick to emerge, questioning the feasibility of this project. Let us take a closer look at what going totally renewable means.
Renewable energy and renewable electricity
Charles McConnell of Rice University’s Energy and Environment Initiative called these pledges silly and misleading, but others were quick to refute his claims afterwards.
Essential to the matter is the difference between renewable energy and electricity. While the latter is only a subset, the former also includes fields such as transportation or heat energy.
However, the basis of McConnell’s claim is that electrons cannot be distinguished from one another, as there is no system that can track solar electrons and coal electrons – once generated, they are simply electrons.
The final mix of electrons is always partly dirty, as no grid avoids fossil fuels for instance, so no city can really consume 100% renewables, argues McConnell. More generally, no large entity can get there unless the grid that it is connected to is directly powered by 100% renewables.
What about energy cleanness?
There is no market of clean electrons and nobody can really claim that, just as there is no entirely clean power. But when an individual or a larger entity contributes to the generation of renewable energy, it gets credit for exactly that energy.
Consequently, if that entity purchases enough of this energy to cover its own consumption, it can claim to be consuming 100% renewable energy. Nobody can directly choose their own electricity source in the utility sector, so the “clean” energy that people are claiming to be consuming is a small portion of an immense pool of energies, some clean, some dirty, with multiple ins and outs.
Where do fossil fuels fit?
In addition, McConnell argues that whatever amounts of renewable energy cities are using, they are built on top of a grid made by fossil fuels.
As solar or wind energy are neither constant, nor reliable and predictable, there has to be a bedrock of coal, onto which renewable energy can find its spot.
David Roberts of VOX argues instead that the coal industry is facing a remarkable decline, being undercut by natural gas more and more.
Grids must be flexible in order to accommodate the fluctuating renewable resources that appear, and coal is the exact opposite of that, since big coal plants work permanently, are slow and are expensive to ramp.
Today’s grids may indeed rely on fossil fuels, but alternative energies will be able to replace this bedrock, especially modular nuclear power.
The idea of cities pledging to get 100 percent of their electricity from renewables actually represents buying an adequate quantity of renewable energy to cover their consumption.
Fossil fuels are surely not necessary for reliability and flexibility. Finally, urban communities do not deceive when making this groundbreaking commitment, but instead, they buy renewable energy and claim credit for the purchase.
Cities are starting to endorse a future where coal and natural gas are obsolete and worthless, while allowing their citizens to support clean energy.
For more details about specific projects around the globe, visit http://www.go100percent.org/cms/index.php?id=19