Guest post by John Morgan. John runs R&D programmes at a Sydney startup company. He has a PhD in physical chemistry, and research experience in chemical engineering in the US and at CSIRO. He is a regular commenter on BNC.
You can follow John on Twitter @JohnDPMorgan
Let’s get one thing out of the way – the parochial title. Graham Palmer’s Energy in Australia is not about Australia, any more than, say, David MacKay’s Sustainable Energy Without the Hot Air is about the UK. Both books make use of local case studies, but they are both concerned with fundamental aspects of our energy system that will interest readers regardless of nationality.
Likewise, peak oil and Asia’s economic growth are minor players in this story, characters that don’t really warrant top billing. So, what is this book really about?
EiA is an extended discussion of the high level issues in energy system transformation, in particular, energy return on energy invested (EROEI), intermittency, and electricity grid control. A short, punchy book of only 80 or so pages, it is broken down into many bite-sized pieces and is an easy read for the non-specialist, despite being published under an academic imprint.
The book argues that solar and wind exist within the existing fossil fuel / synchronous grid framework, and have a role to play in abating emissions from those plants, and in network peak load support, but that they do not allow us to break out of that system. That would require an energy source with high EROEI driving synchronous generators that can progressively replace those driven by coal and gas in the existing grid.
The system level issues are summarized by Palmer in the figure below, as they relate to plans for renewable energy. Many proposals for 100% renewable energy systems put together some combination of wind, solar, biogas, etc. that meets historical demand. As Palmer puts it,
The underlying theme of 100% renewable plans is the assumption that through increased complexity, an optimal set of synergies can be discovered and exploited. The difficulty is that the plans operate solely within the shallow “simulation layer” … With few exceptions, little consideration is given to the deeper first- and second-order layer issues.
The first half of the book explores those deeper issues, and is a fascinating description of the operation of the grid, its control schemes, the role of baseload, peak demand management, storage, capacity factors, availability and so on. This really should be compulsory reading for anyone serious about a transition to a low emissions electricity grid.
A startling figure from this discussion is the world’s electricity generation mix expressed, not as contributions from coal, gas, hydro, wind etc. as we usually see, but as the fraction from “synchronous rotary machines” – that is, mechanical generators with rotating shafts which are synchronized to the electrical frequency of the grid. 96% of global electricity is provided by such machines. In a sense, we have almost no diversity in electrical generation.
These machines are ubiquitous because they offer a solution to the historically difficult problem of grid control – making sure that electricity generation exactly meets demand at any instant. This is done by frequency stabilization – the rotation of all the generators on the grid is synchronized, and as loads are connected to the grid, the rotational frequency drops, which is the signal used to bring on board new generation.