Mastering peak demand and micro-storage

More can be done to alleviate peak demand via PV, efficiency and policy while, elsewhere, there are some emerging opportunities for storage from supercapacitors.

The January 2014 extreme weather in southern Australia reignited debate over the role of air conditioners in driving peak demand.

A few issues have emerged. A thoughtful study by Ric Brazzale of the REC Traders Association reframed debate about how useful PV is in managing peaks. Since electricity data from the Australian Energy Market Operator  does not include PV output, because it happens on the consumer side of the meter, Ric recreated the real demand profile by adding estimated half-hourly PV output to the AEMO demand profile. This showed actual peak demand occurred earlier in the day, when PV was producing much more electricity.  

This challenges the simplistic approach usually taken, of just looking at PV output at the time of the AEMO peak. Ric also pointed out that PV helped to significantly reduce average prices on peak days below those before the Black Saturday fires.

Of course, reducing peaks and peak prices undermines generator and network profits, which is seen as a bad thing by the incumbents and some policy makers. As demand-response bidding, energy efficiency and energy storage progress, summer peaks will become less of a problem – and less profitable for the electricity industry.

I can only wonder how much cheaper electricity costs would have been if the networks had invested in these solutions instead of more powerlines. As the owner of a small high-efficiency air conditioner operating in a well-insulated and shaded room, my peak cooling load in the heatwave was around 300 watts during ‘cool down’ on arriving home, and around 125 watts at times of extreme heat. That’s much less than a plasma TV or six halogen lamps.


All this brings me to an issue raised in the 2013 book Smart Utopia? by Yolande Strengers. She asks why the electricity industry is expected to provide unlimited power supply at all times. This piqued my interest. In industry, I have found that the engineers who provide services such as steam and refrigeration often run grossly excess plant (and waste a lot of energy) in their quest to provide as much energy as users ask for, even if the request is unreasonably high.

In the 1980s, I found the electricity industry shared this culture. There is certainly a historical reason for this: without our modern energy options (which allow us to reduce and shift demand), many activities were critically dependent on reliable electricity supply. Indeed, many activities still are, but need not be. The political price of supply shortages has traditionally been high, as daily life, health and business activity have been affected: heads of electricity agencies can lose their jobs, politicians can lose power. Engineers have a professional pride in providing what their clients ask for, and don’t like being blamed for shortfalls. But modern energy solutions allow us to limit expectations of the traditional electricity supply system and, instead, place some responsibility on consumers.

Such expectations would need to be phased in, with issues faced by tenants and financially stressed people recognised and transitional costs addressed. Incentives and support mechanisms, not just pricing, must be used. The alternative may be a mess, as those who are active, informed and have access to capital will look after themselves while others suffer. This should be a core focus of energy reform policy.

Energy issues paper

In mid-December 2013, the government released an Energy Issues Paper and called for submissions by February 7, 2014. This process is a lead-in to release of a Green Paper in May and an Energy White Paper in September. The Issues Paper seems to be focused on a list of short- to medium-term problems that the government thinks it needs to address. As far as it goes, this is useful, although the way issues are presented seems to disproportionately reflect the views of incumbent energy organisations and some policy makers.

Hopefully the Green Paper will take a broader view. Let’s face it, when the phrase ‘climate change’ does not appear in an energy policy document, our policy makers are struggling to be credible. And I wish energy policy people would learn to differentiate between the price of energy and the cost of delivering energy-related services. Price matters much less if you are efficient and can avoid periods of high prices. The policy focus on price distorts energy policy towards measures that increase long-term total costs and social and environmental impacts.  

Standing Council on Energy and Resources delays demand management bidding, yet again

A major criticism by the 2012 Senate Inquiry into the electricity industry, and by the Productivity Commission’s 2013 report into electricity networks, was the glacially slow progress on implementation of demand-side action. The Parer Review of 2002 and other studies have repeatedly highlighted the  need to get the demand side of the market  working. So it was very disappointing to see the ministers from states and Commonwealth on the Standing Council on Energy and Resources decide at their December 2013 meeting to delay, yet again, rule changes to support implementation of a demand response bidding scheme. The only winners from this delay seem to be incumbent electricity generators and network owners.

And some more demand management in the January heatwave would have been handy.  

Sydney car trips

The bizarre outcomes of a car-based society were reinforced for me recently by some NSW transport statistics. Apparently 22 per cent of all Sydney weekday car trips are to ‘serve passenger’. That is, they are unpaid chauffeuring trips, where the driver doesn’t actually want to go to the destination. What is the cost of this planning failure in terms of time, inconvenience, congestion, parking issues, pollution, health and lack of independence?

Surely it is time that local and state governments ensured our cities supported low car-dependency living? This would be much better for the young, old, parents, disabled, carers, poor and obese.

Emerging opportunities for energy storage

I wonder who will be first to actively promote an easy-to-add-on storage and smarts package for existing rooftop PV owners? This makes good business sense because hundreds of thousands of PV owning households are getting only 8 to 10 cents per kilowatt-hour for their exports, while paying 30 to 50 cents for energy in peak periods. These people are already committed to PV and frustrated with the efforts of the electricity industry and its policy makers to undermine their financial returns.

A second area for storage that I haven’t seen discussed is at the micro-level, building storage into appliances, or integrating (or plugging in) storage into local wiring within a building. This limits peak demand charges, offers potential savings on upgrading wiring and reduces wiring resistance losses in existing buildings.

Advances in supercapacitors may play a key role here. New Mazda cars use them instead of batteries for energy recovery and storage, and the CSIRO-developed UltraBattery uses supercapacitors to mediate between the battery and the load, to extend battery life and reduce losses. Research on graphene also seems likely to improve supercapacitor  performance. One example of this potential is in the installation of induction cooktops in existing homes. Most induction cooktops have ‘boost’ modes that can use over 3 kilowatts per pot, so manufacturers can claim they heat up quicker than gas. This potentially high peak demand can require upgrading of wiring back to the circuit breakers or even back to the street. But the amounts of energy required  are not particularly large, so quite small  amounts of storage would make a difference. For example, to boil 2L of water on an induction cooktop consumes less than a  quarter of a kilowatt-hour. A proviso is that the benefits must be balanced against the losses in the storage system. When you look at the fine detail, the economics of appropriately designed distributed storage solutions could be much better than many expect.

Small-scale energy storage would make a difference in the wiring required and peak energy demanded by appliances such as induction cooktops
Graph for Mastering peak demand and micro-storage

Alan Pears has worked on sustainable energy issues since the late 1970s. He is one of Australia’s best recognised and most highly awarded commentators on sustainable energy and climate issues. He teaches part time at RMIT University and is co-director of Sustainable Solutions, a small consultancy.

This article originally appeared in Renew magazine. Reproduced with permission.

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