Grid-scale Electricity Storage – why it cannot work

This is a paper by John McBratney B. Tech (Electronic Engineering), formerly MIE Aust, MIEEE, Electronic Systems Engineer, Rtd.

So-called big batteries will not work to store the amount of power required to ride through windless nights for two reasons. One is the astronomical cost of the batteries required to store hundreds of GWh of power and the other is the impossibility of generating enough excess power to charge the batteries.

Large Battery Capacity

Grid maximum capacity batteries currently available from around the world are all around a maximum of 500 MWh hours in energy capacity. Their power delivery capability is of the order of 250 to 350 MW. By all accounts these are indeed large batteries, they occupy extensive geographic areas and have significant deleterious effects on local land use and resident flora and fauna.

However, large as they may be by current battery standards, the largest of them are still totally inadequate as a fill-in power source for large city supply over a windless night. The deficiency is in multiple factors of 10.

An example is the Moorabool battery recently commissioned in the state of Victoria near Geelong. It is specified as having a capacity of 450 MWh and an ability to provide a power output of 250 MW. To put this in perspective the power consumption of Victoria at the time of writing (2030 hrs on 20

January 2024) is 5,177 MW. If, for the sake of this discussion, it is assumed that this figure reduces by 20% to an average of 4600 MW over the dark period to say 1800 hrs to 1000 hrs, the next day.

And assuming effective solar power generation ceased at around 1600 hrs today this would result in an energy load in this period of no sun of 16 x 4600 = 73,600 MWh. The battery can only supply 450 MWh. The deficiency is over 73,00082,000 MWh, a factor of 163 times too small, it is so far out as

to be considered completely useless.

Useful Battery Service

Grid connected batteries of the above type and capacity can serve a useful purpose as “peak lopping” facilities. That is to say that they can supply a short term additional power resource to the network during the higher morning load and evening load periods. They are then re-charged during the lower load periods of the day when the cost of power is likely to be negative so they are paid to recharge!

Storage Re-charge

Clearly any storage system requires that the depleted energy be replaced by some re-charging process. This applies to batteries, pump hydro facilities, biomass and hydrogen storage systems and any other storage mechanism. Each time the stored energy is used, it has to be rapidly replaced for the next time it is required.

That process does not happen immediately because energy drawn from any storage system can only be replaced (re-charged) at approximately the same rate at which it was originally utilized, plus in fact around 30% additional time as a result of inherent electrical losses.

The energy required to re-charge a storage system is in fact the same amount as was delivered in the first place, plus the additional 20% - 30% for coverage of losses. Thus the grid has to supply the normal grid load plus a further load - that is 120% - 130% above the normal load in order to re-charge the storage system. Such an increase in the grid capacity is unlikely to be financially acceptable or technically feasible.

The Supply Chain for Battery Materials

Proponents of large battery storage systems routinely ignore the supply

chain for materials that go to manufacture of batteries. The base minerals required for batteries, such as Lithium, cobalt and other rare metals are mined primarily in developing countries (and China) that do not have effective workplace health and safety regulations. There are documented work conditions in mining that involve slave and child labour.

Work conditions are also often atrocious and would not be acceptable to modern Western developed country standards. These abuses of children and adults alike continue unabated as the Western powers maintain a steady importation of the above minerals for the manufacture of renewable energy products, specifically but not limited to, Lithium ion based storage batteries.

It is clear that such human abuses do not raise the concern oof Western consciences and their

pursuit of financial gain is at the expense of abhorrent human abuse in underdeveloped countries.

A further blight on the moral and ethical behavior of developed country policy makers and commercial entities engaged in construction and implementation of renewable energy systems, including batteries, transmission lines and wind turbines is their lack of concern for the destruction of agricultural land, and the eradication of habitats for native flora and fauna.

The positions taken by government and related organisation that the implementation of renewable energy systems is a “green” activity is thus entirely false, fraudulent and a deliberate lie to the general public.

Conclusions

The rather obvious conclusion is that storage, using either batteries or indeed any other storage mechanism, cannot ever work as a fill-in facility for the common-mode failure of solar and/or wind generation systems.

There are two main reasons:

One, there is inadequate capacity in any known storage system to provide the level of energy required to compensate for the normal grid load, with the very limited exception of very large pump hydro electric systems.;

Two, a depleted storage system has to be re-charged almost immediately, which that is patently impossible.

No charging system is immediate and in addition in any grid system it would require a grid capacity increase of over 120%.

Storage systems ALL require re-charge and inherently require some 30% more time to re-charge than was taken during discharge. This vital point is very often ignored, indicating a lack of technical understanding of storage systems.

Written JMcB 28 JAN 2024

Updated 10 February 2025