Rolling Blackouts and Renewable Energy Operated Networks – Part 1

In this post I explain what rolling blackouts are and why capital cities around Australia are likely to experience these until the country shifts to renewable energy infrastructure from 2030.

What Is A Rolling Blackout?

A city’s electricity network is less robust than most of us think. Infrastructure and utility companies employ a whole workforce of electricity network managers and technicians to keep checks on and correct instabilities in both production and supply of electricity so that we can continue to have stable, predictably electrified homes 24hrs a day, 7 days a week.

Sometimes the magnitude and/or number of network instabilities are such that they cannot be corrected through the usual procedures followed by network managers. In those cases, as a last resort and to protect the entire electricity grid from breakdown, a rolling blackout strategy is enabled.

A rolling blackout is a maneuver executed by electricity network managers. In a city scenario electricity supply is temporarily turned off to a few districts (parts of the grid spanning a handful of suburbs) at a time. If the instability is not resolved, the first few districts will have their electricity turned back on again, but a few others will have to be switched off. This process continues a bit like a Mexican wave rolling across the entire city until the instability is resolved.

What Causes Grid Instabilities and Blackouts?

In a traditional electricity network set-up, instabilities are caused when power consumption outstrips supply; a traditional example is when a city and its population has expanded very rapidly.

A very simple way to think about it is that of power literally running out like having no more timber to burn in your fire place.

The electricity company plant cannot produce enough energy to cater for the population growth so it has to perform a rolling blackout in order to deliver electricity to all customers for say 20 hours a day rather than some customers for 24 hours and other customers for just 2 hours that day.

When electricity generated from renewable resources is involved, the instabilities are caused by too much power being produced by sources other than the power plant.

Using the same fireplace example as above the instability is like overfilling your fireplace with burning wood which if spilled outside of its fireplace system, it can cause fires in places you did not want consumed by flames.

Transformers, which can be compared to larger versions of residual current devices (RCDs) found in domestic switch boards, are pieces of equipment that deal with oversupply by tripping (switching themselves off) whenever too much electricity is flowing through them. In this manner infrastructure fires are avoided and disruptions to power supply are localized.

Transformers are connected to districts, therefore when one transform trips a blackout occurs in the districts it serves. This is a blackout caused by equipment safety, not one planned and performed by human beings. Unlike rolling blackouts, the tripping of transformers is unpredictable which means the electricity company is unable to schedule staff properly to attend to transformers shut off.

Even when transformers are attended to, they are likely to trip back off shortly thereafter because the electricity overflow issue is caused by customers roof mounted solar panels. This leaves the customers without electricity and the electricity company unable to fix the problem because it is cause by infrastructure which belongs to customers.

Similarly to the traditional scenario, the electricity company implements a rolling blackout strategy so that it can provide electricity for the longest number of hours possible to the largest number of consumers. The rolling blackout is to remove the unpredictability of transformer shut-off and to stay ahead of customer produced electricity spikes which caused the problem in the first place.

To go back to the fireplace example, the rolling blackout is a way of burning off some of the wood in your fireplace to make room for and before more wood arrives into your fireplace from somewhere you cannot control.

So What Really Causes the Need for Rolling Blackouts?

In my opinion it is the mixing of two systems made for different purposes.

In short, solar fueled electricity was meant to replace not work side by side with traditional fossil fueled electricity production as is the case at the moment.

Many of the issues experienced or predicted to be experienced by Australians cities in relation to rolling blackouts, electricity production and availability in general, are due to the successful social implementation of rooftop solar panels that produce renewable resource fueled electricity.

Electricity infrastructure was designed for electricity to be produced in a factory which had all the voltage, and to be delivered to sites that made no electricity of their own or which had zero voltage. The entire system was based on the observed physical properties of electricity which show this form of energy only ever flows from high voltage to low voltage (never the other way around).

The installation of solar panels on residential roofs means the flow of electricity is now not just from a factory but from houses themselves. The physics have not changed, but the set-up has caused a situation where both factory and houses have voltage.

Where have the low voltage areas gone for electricity to flow to? If these areas do not exist anymore, electricity’s energy is lost as heat in equipment like transformers which, as I mentioned before, are designed to trip to prevent electrical fires.

Solar panel electricity production was originally designed to charge large banks of site stored barriers which could be used for electricity during periods of darkness. The current setup of solar panels on the roofs of houses makes use of no site stored batteries. This equipment omission is one of the causes for needing rolling blackouts strategies and perhaps one of the few ways architects and engineers can directly engage with creating a solution until Australia’s transition to renewable electricity networks is complete.

If you are interest in operational hands-on aspects for providing solutions in this area, you’ll be pleased to know I plan to post on solar electricity equipment issues and technology advances...

Will The Problem Get Better or Worse?

I think rolling blackouts maneuvers will increasingly be used by power companies to deal with excess energy in the grid.

Having said that I am quietly optimistic about the change over from coal fired power stations to renewable powered energy production which is to take place beginning 2030 and believe the decision to create the dual system was a necessary political maneuver to have most of the population sold on renewable energy prior to the big shift over.

Expect a post on the social and political aspects of rolling blackouts and renewable energy operated networks very soon…

References – websites accessed and correct at time of publishing.

For a bit of background on issues facing Australian capital cities due to renewables fueled electricity production: https://www.abc.net.au/news/2018-10-11/electricity-distributors-warn-excess-solar-could-damage-grid/10365622

For basic physics on how electrical fires start see Bill Jones answer to “How does an overloaded circuit cause a fire?”: https://www.quora.com/How-does-an-overloaded-circuit-cause-a-fire

For further background on rolling blackouts: https://completeelectrical.biz/exactly-rolling-blackouts/