Congestion and Bottlenecks
Understand how congestion develops as grid demand grows. Consider the impact of bottlenecks that arise as a consequence.
In our last two posts we considered Inertia and its importance to grid operations - the discipline of keeping the electricity supply in a stable and balanced state.
In this post we look at how congestion on the grid arises and the particular challenges it presents. Grids are catering to rising remand almost everywhere, at a rate of growth that hasn't been seen for multiple decades. In the transformation to NZE, demand in 2050 is pitched at almost 3X1 the level in 2020, as increased electrification of devices compounds the pressures added by population growth. Just keeping up will be a big ask.
With the passage of time, grids develop weak spots and pinch points for assorted reasons - ageing infrastructure, growth in demand from urban and industrial developments, the rise of renewables and storage, the ongoing journey to decarbonise. Crypto mining was barely a category a decade ago, but now consumes electrical energy2 on a par with sovereign nations such as Poland, Thailand or Vietnam. AI has become the predominant driver of data center buildout and grid demand on a scale that will comfortably outstrip crypto3.
Investment in capacity doesn’t always anticipate or even keep up with these developments, and grid operators must find workarounds to avoid supply interruptions to consumers. Grid congestion arises and bottlenecks become a more pervasive problem.
On the supply side: The growing fleet of renewable generation sites – particularly utility scale wind and solar farms – face connection queues, many quite significant. Grid operators cannot simply connect new capacity at will. Expanded transmission, interconnection and distribution capacity must be put in place. Local planning and permitting processes, ecological and environmental concerns must be respected.
On the demand side: Infrastructure that connects the Grid to consumers must be expanded and retrofitted:
- Expanded to create new connections to cater for demographic and geographical shifts and growing population
- Retrofitted/upgraded to deliver proportionately more power through existing infrastructure as consumers switch to ever higher levels of device electrification
The pace of grid upgrades is an ongoing challenge. It's reasonable to expect that buildout will catch up in due course, but that may be decades away given the slow pace of many planning systems coupled with relentless demand growth. In the meantime, the intraday peaks in demand will cause periods of stress on grid segments where demand pushes ahead of the grid builders’ ability to keep pace with new demands.
Every channel becomes a bottleneck when you try to push too much through.
Most grid congestion is time dependent. In periods of stress, the grid operator cannot simply force through additional electrical power to meet demand. When this happens, grid balance and stability are threatened in that grid segment (for reasons outlined in our earlier post).
These bottlenecks increase the likelihood of service interruptions and generally impair the grid operator's ability to maintain acceptable service levels to their consumers.
Even if infrastructure developments proceed at an impressive pace, new ways of moving energy at off-peak times will be needed as a workaround to bottlenecks. A combination of Bulk Energy Shifting and enhanced Smart Grid affords grid operators the opportunity to delay, reduce or even avoid the infrastructure upgrade
A new model of distributed storage (we'll post on this later) is required to enable off-peak Bulk Energy Shifting. Read about Smart Grid next.
References
- An updated roadmap to Net Zero Emissions by 2050 - World Energy Outlook 2022 – Analysis - IEA
- From Cambridge CBECI's interactive country comparison tool
- From Science Daily (Oct 2023) citing Joule - Powering AI could use as much electricity as a small country