Renewables: Total Electrification
Updated: Mar 25
At the heart of virtually all climate change proposals such as ‘Net Zero by 2050’ is a plan to switch from fossil fuels to alternative sources of energy that do not emit greenhouse gases. These alternatives include solar, wind, hydro-electric and ocean (wave and tidal) power.
In this series of posts we consider some of the engineering, project management and financial realities to do with switching from carbon-based fuels to alternative energy sources.
The first three posts in the series were:
Renewables: The Paradox We look at the apparent paradox that renewable energy sources are growing much more quickly than carbon-based fuels, yet their share of the energy supply is declining. (This is because alternative energy sources have not been replacing fossil fuels; instead, these new forms of energy have merely provided a large fraction of the additional energy that we are using.)
Renewables: Not Fast Enough In spite of the fact that renewable energy sources (principally wind and solar) are growing quickly, their growth is not fast enough if they are to carry the bulk of society’s energy load just three decades from now.
Renewables: Supply and Demand Renewable energy sources — primarily solar and wind — are intermittent or non-dispatchable. They are available only around 35% of the time, depending on location. Moreover, there is generally a mismatch between the time when they are most available and when the customers need the power that they supply. These difficulties can be addressed, but not solved, through the use of backup power supplies, energy storage and the use of a smart grid.
In this fourth post we look at one of the implications to do with the use of renewable energy, and that is the fact that our energy systems will be totally electrified.
Previous posts have started by considering some of the insights provided by the BP chart published for the year 2020.
The breakdown for the year 2019 in round numbers is as follows,
Natural Gas 26%
Therefore, about 85% of the energy that we use comes from carbon-based fuels (rather misleadingly called “fossil” fuels). When these fuels are burned, the energy that they release is used to power virtually all aspects of our modern society. Some of that energy is used directly (for example, in internal combustion engines), and some of the energy is converted into electrical power, most of which is fed into the grid. Either way, they generate CO2 and other greenhouse gases. Regardless of how the energy is used, our current system is hydrocarbon based.
Renewables, on the other hand, generate electricity directly. This is good and bad. It is good because they do not create greenhouse gases. However, in a ‘Net Zero’ economy, some of the energy has to be converted to chemical fuels such as hydrogen and ammonia. They do not directly create liquid or gaseous fuels to be used in transportation; nor do they provide feedstock for the manufacture of the amazingly wide range of chemicals that our society uses.
Therefore, a switch from carbon-based fuels to renewables requires a profound and fundamental shift in the manner in which we manage and use energy, as shown in the following sketch. In future posts we will unpack the contents of this sketch. For now, it is sufficient to note that all of the primary energy sources, from solar to ocean energy, generate electricity, and that some of that electricity has to be converted to chemical fuels.