The Road to Net Zero - Part 2
- "Whole Energy System" Thinking
As we electrify heat and transport, the boundaries between previously separate energy systems are disappearing.
Heat, power and transport were traditionally treated as largely separate engineering problems. Increasing electrification is bringing them together.
Replacing gas heating with heat pumps increases electrical demand. Electrifying vehicle fleets creates potentially substantial new loads. Solar and wind introduce variable local generation. Battery and thermal storage allow energy supply and demand to be shifted through time.
The individual technologies cannot therefore be properly assessed in isolation. There is no single technology or "magic bullet" that provides the optimum solution.
At Sonas Energy, we are proponents of whole-system thinking.
In practical terms, this means considering together:
• energy demand and opportunities to reduce it;
• how electricity and heat requirements will evolve over time;
• the impact and phasing of electrification of heat and transport;
• available and evolving grid import and export capacity;
• opportunities for on-site and off-site renewable generation;
• battery and thermal energy storage;
• the changing cost and value of energy at different times;
• more flexible infrastructure, including private-wire and local energy networks; and
• digital control and flexibility, allowing demand shifting, energy arbitrage and greater use of locally generated energy.
The important point here is not the merit of individual technologies rather it is understanding the interaction and deployment between them.
For example, electrifying heat may appear to require substantial additional grid capacity. But reducing demand, adding local renewable generation, introducing thermal or electrical storage and managing when loads operate can produce a very different infrastructure requirement.
Similarly, a battery considered simply as a means of storing surplus solar generation may have a weak business case. The same battery considered as part of an integrated system—supporting peak reduction, flexible tariffs, increased renewable self-consumption and management of grid constraints—may have considerably greater value.
Whole-system thinking therefore changes the question from:
Which technologies should we install?
to:
What combination of technologies, infrastructure and operating strategies produces the best overall energy system?
Recognising the increasing coupling between heat, power and transport was a central theme of the original Sonas work on pathways to net zero. As electrification has accelerated, that principle has become increasingly important.
In Part 3 we look at one of the most important consequences: why annual energy figures are not enough, and why matching supply and demand through time is fundamental to designing the optimum system.