I think more people need to understand this concept that was attributed to Michael Liebriech, a thought-leader in the energy transition. Sam Hamels just wrote a pretty short explainer of its implications on Linkedin, which I encourage you all to read.
The assumptions are simple and does not address some of the other obstacles along the way but it is important that we should not be overwhelmed by the gross energy requirements in primary energy terms when we recognise that a lot of primary energy in the form of fuel are lost in the process of converting them into energy.
There are other obstacles along the way however, when considering that the most viable and economic renewable electricity sources are typically wind and solar, with substantial hydropower in the mix for certain geographies. These include:
- Transmission and distribution infrastructure:
- Hydropower tends to be farther away from demand centers so the distance of transmission makes the infrastructure expensive
- Wind and solar tends to be intermittent which means that a lot more needs to be transmitted during the times they are produced while the infrastructure remains underutilized when they are not available
- Overall capacity will need to be increased compared to the fossil energy regime
- Energy storage infrastructure:
- While hydropower dams could benefit from becoming pumped storage, other renewables such as wind and solar will require significant energy storage in the grid in order to reduce the need to overbuild (because of the point above)
- Energy storage will also help provide the ancillary services for the electricity system as fossil plants retreat from the system (eg. reserve markets, frequency and voltage supports) while it becomes more volatile due to intermittent renewable electricity.
- A lot more investment into stationary energy storage will be required. At least before the more lofty vehicle-to-grid concepts kick into place.
- End-use system/equipment changes
- To reap the benefits of the improved efficiency of an electricity based energy system, there will be a need to electrify more which means end-use equipment will need to be changed – assuming we’re trying to change a whole fleet of equipment with no regard to remaining lifespan, we are not properly using up our invested assets.
- Typically, fuel-driven systems have longer lifespans than those driven by electricity – that may have to do with the fact that fuel-driven systems are more mechanical and have less delicate circuitry systems. Of course, that varies with specific use-case and appliance but what this means is that you might still face more frequent replacement, and the environmental cost of that might need to be carefully considered.
- In some cases, the change in end-use equipment requires further infrastructure support. The most important example is electric vehicles, which need the support of a robust charging network – that must be supported by improved distribution networks in the grid.
- Besides the grid, institutional improvements that properly allocate costs and reflect them to customers are necessary as well. Sometimes, it may make the transition harder as well. For example, the peak demand pricing of electricity markets drove a bakery in Queensland Australia to change their electric ovens to gas fired ones because they absolutely have to bake their breads in the early hours of the morning.
Now the reason I’m listing all these other obstacles is to challenge us to think through the solutions needed having convinced ourselves that we actually can work on getting enough supply into the system. There is still a lot of work to do to ensure this supply actually matches the real demand. Looking at gross energy terms is simply not enough, as evident from the primary energy fallacy itself.