Features Australia

Battery battles

Bandaids for the Californian disease

29 August 2020

9:00 AM

29 August 2020

9:00 AM

What do you do if the electricity grid is under strain, major users are being paid to stay off it on days of high demand and reliable, conventional power plants are being retired with no replacements? If you are the state of NSW you ignore this problem and certainly pay no attention to the troubles of the American state of California where extensive reliance on renewable energy has resulted in a rolling series of blackouts during a heatwave – a problem that neighbouring states facing the same conditions but with fewer renewable projects have managed to avoid.

Instead, NSW and other states are evolving a patchwork, unsatisfactory solution to the problem of using renewables they have created in the first place – a host of batteries.

This solution was highlighted in a mid-August announcement by the NSW government of a $270 million project combining large conventional batteries, a gas hybrid plant and another project dubbed a virtual battery. In addition, AGL Energy has unveiled plans to transform its Liddell coal power plant in NSW into an electricity storage facility.

In South Australia, the much vaunted Hornsdale battery project is to be expanded by 50 per cent, mainly by using public money, and other projects are being planned for Queensland and Darwin as well as elsewhere in South Australia and NSW.

All of this activity is being sold to hapless consumers as Australia shifting to the green nirvana of distributed power plants made up of windfarms and solar installations backed by these batteries. This cover story would be easier to swallow if California was not being plunged into darkness and the journalists, with honourable exceptions, did not get into a thorough muddle over the use of megawatts (MW – output) as opposed to megawatt hours (MWh – storage or capacity).

Lack of experience in technical matters can be excused, but in America the announcement of an enormous battery project by Californian energy company PG&E in Moss Landing (Monterey) California, made weeks before the lights in the state went out, takes non-disclosure to new levels.

The project will use Tesla batteries to store 730 megawatt hours (MWh) of energy which it can release to the grid as 182.5 MW for up to four hours – a trivial amount, especially in relation to the size of the Californian grid, but enough to make activists scream that the energy revolution is upon us. The euphoria is such that ephemera, including how much the project actually cost or what strategy might be used in releasing such small amounts of energy to the Californian grid, do not make it into the reports.

The issue is further confused when activists insist that the NSW and Moss Landing projects are the start of a revolution by which batteries will take over the storage task for major grids without stopping to consider just how many batteries will be required (millions plus continual replacements). Sceptics are told that the recent decline in battery prices and improvements in technology will continue far enough to make them usable as grid storage, irrespective of resource and manufacturing bottlenecks.

All that said, such projects will have some use in fixing the problems created by the use of renewable power on a large scale. The first of these is the supply of various ancillary electricity services, notably frequency management. For not only does electricity supply have to be matched with demand on grids 24/7, the frequency of the alternating current has to be kept stable. This is 50 cycles a second or 50 hertz in Australia (60 in the US).

Coal and gas generators churn out power at that frequency with ease, automatically synchronising with one another on a grid, but wind generators and solar power plants don’t do this. Batteries are a solution and can make some money in this field if only because of the erratic nature of new-age power.

When the South Australian grid became a power island after the interconnector with Victoria went down at the end of January, only a small number of providers in SA itself were offering frequency management services. As a result, as noted in a National Energy Market report on the issue, for a week frequency management on the grid cost three and a half times more than the supply of power itself for the state. This extraordinary situation in only a small part of the NEM has since been corrected by a partial restoration of the link between Victoria and SA, but it is only one of a series of growing problems in this long-promised nirvana of renewable energy.

Another problem reported by the Australian Energy Market Operator and this time noted in the mainstream media is that of the increasing difference between daytime and night-time demand peaks. The daytime peaks are being reduced by the increasing number of rooftop PV panels particularly in SA, when the sun shines, but the night-time peak remains unaffected. The conventional, despised fossil fuel plants then have to power down during the day and power up at night. As they date from a previous era of power generation, they were never designed to do this and are not being replaced by plants that can ‘load follow’ – change output to suit the load on the grid.

Batteries can at least partially offset these problems by shifting peaks. In addition, and much more importantly, they reduce the need for spinning reserve, which involves keeping a number of conventional plants offline but operating, ready to be hooked up at a moment’s notice when the wind cuts out or the sun goes behind a cloud. Some spinning reserve has always been necessary on conventional grids but renewables add substantially to the problem.

Batteries can at least maintain output while conventional plants are brought online, provided the conventional plants have not been forced out of business by government policy as has occurred in California, and at a price.

The NSW announcement involves $37.5 million in state government money and $233 million in private investment. The Hornsdale 100MW/129MWh project is being expanded by 50 per cent for $79 million, with the SA state government chipping in $15 million, the Australian Renewable Energy Agency putting up $8 million and $50 million in project financing coming from the Clean Energy Finance Corporation.

This adds up to a lot of government money for a partial fix, at best, of a problem created by government policy in the first place and is no solution of all to the problem of keeping the lights on during any prolonged period of no wind.

Energy policy in Australia owes little to sanity.

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 Mark Lawson www.clearvadersname.com

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