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Jamestown: distinctive features
Shire to go solar?
Where will it end?

'Death spiral': one more step

Power consumption from the Australian power grids has decreased in recent years leading to less income for the grid operators. Big money has been spent on upgrading the grid ready for increased consumption that didn't happen and doesn't look like happening in the foreseeable future.

In an effort to get a return on their investment the grid operators have increased power prices. This has resulted in more people reducing consumption with energy efficiency measures and adding more solar PV to their roofs and some consumers going off-grid all together. Less consumption results in higher prices which leads to less consumption which leads to still higher prices and so on until the operators of the power grid go bankrupt. This is what has been called the death spiral of the power grid.

The only thing that seems certain to me is that the operators of the Australian power grid are going to have to make some big changes to their expectations and business models if they are to survive.

Written 2014/05/15, modified 2015/04/15
Contact: email daveclarkecb@yahoo.com (David Clarke) – ©
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Floating PV panels proposed for Jamestown, South Australia
Floating PV panels
Image credit ABC
The 'death spiral' of the power grid has taken another small step with a publicly announced proposal.

An announcement on ESCOSA's Net site started with the following:

"GEITS ANZ Pty Ltd has applied to the Commission for an electricity generation licence to operate a 400kW photo-voltaic solar system to be located on the Northern Areas Council Waste Water Treatment Plant in Jamestown [in South Australia's Mid North]. The generation plant will initially operate to supply electricity to the adjacent Timber Mill ( Morgan's Sawmill ). Subject to technical requirements, it may also supply electricity to other customers in the township of Jamestown."
So what? 400kW is large for a solar PV installation in Australia, but not unusually so.

Apart from the dual use of the solar array – for reducing evaporation as well as generating electricity – Geits ANZ is intending to use it to supply 'behind the meter' power to one or more businesses that are at some distance from the installation; in effect setting up a micro grid quite separate from the eastern Australian electricity grid. It will be about 600m from the saw mill and two and a half kilometres from the centre of Jamestown. It will supply cheap electricity that will replace expensive electricity that would otherwise come from the power grid.

This is what the grid death spiral is all about. Solar PV power is now cheaper than grid power, so long as it can be delivered to the retail consumer without going through the grid. Retail grid power prices are expected to rise because of rising gas prices. Every increase will make installations like this more attractive.

Unless our pro-coal and renewables-averse Federal Liberal Government makes this sort of thing illegal or economically unviable, the end result will be that the grid will just fill the gaps in supply when the sun isn't shining. Coal fired power stations don't suit this kind of supply; they are much more efficient if they can run continuously. Gas fired generators are well suited, as is hydro and pumped hydro, and unlike gas, they have the great advantage of being sustainable.

An ABC article on the proposal was written by Matthew Doran.

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Distinctive features of the Jamestown proposal

Apart from the micro-grid implications, the installation is unconventional in that it is to float on one of the town's common effluent treatment ponds. In addition to the obvious purpose of generating power the proposal has two further aims:
  1. To greatly decrease the highly problematic amount of evaporation from the pond;
  2. To use the water to keep the panels cool and thus increase their efficiency.
A point that was not made clear by the press releases is whether the panels will be in direct contact with the water? If there is an air-gap beneath the panels this would greatly reduce the cooling effect of the water on the panels.

An open body of water stays cool by evaporation. Placing any sort of cover over it, stopping evaporation, will cause the water to get much warmer. However, if the panels are in direct contact with the water they will lose a lot of heat over night due to the very efficient passive cooling by radiation made possible by the highly effective radiating surface of the solar panels.

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Warrumbungle Shire to go solar?
Public lighting costs to increase by 113%?

Sophie Vorrath reported that the Warrumbungle Shire Council is expecting a huge increase in the cost of public lighting and is consequently investigating installing solar PV on all its suitable buildings (between 80 and 100).

This decision follows a plan by state government owned network operator, Essential Energy, to increase its charges.

If it is viable for the Warrumbungle Shire to go solar, it will probably also be for all other NSW rural shires.

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Where will it end?
What will the 'death spiral' lead to?

Trying to predict anything like this is full of risk and I will probably be wrong, but it could be interesting to make an effort to imagine where Australia's electricity supply may be heading.

 

Battery prices

The future of the power grid is very dependent upon the future cost of storing electricity. To May 2014, when this was written, there has been much optimistic talk of future declines in the price of batteries, and there has been a huge amount of research into batteries. However, the fact is that there have not been declines in battery prices on the same sort of scale as the declines in wind turbine or solar PV costs.

I suspect that while there will be some declines due to mass production, they will not be so great as to make batteries viable for storage of electricity for purposes such as cooking, air conditioning, water heating or home heating.

 

Another step

By July 2014 several large shopping centres had announced or built very big solar PV installations and IKEA had announced that it was going to go solar with its Eastern Australian stores.

The cost/benefit ratio of solar PV for businesses such as shopping centres and supermarkets has reached the point where it would be foolish to not go solar.

First: the decline in the amount of power coming out of the grid will continue and the owners of the infrastructure will have to accept that they have over-invested and they will not get an acceptable return on their investment. They will have to write-off their losses. The alternative, to keep on increasing power prices with the result that more and more people leave the grid, would do the power companies no good and could do them a great deal of harm.

Whether or not the power companies write off their losses and keep power prices within reasonable limits, if battery prices continue to decrease, as it seems likely that they will, there might come a point at which it is economically viable for households to leave the grid, relying on solar PV with battery back-up. Of course the higher the electricity prices the earlier this point will be reached. One disadvantage to the householders in leaving the grid would be that they would then not be able to sell their excess power.

There are environmental costs with batteries. It remains to be seen how much of their materials can be recycled, how much has to go into land fills, how much must be replaced by continual mining, and how much pollution battery production creates.

Business and industry uses far more power than householders and they pay lower prices per kWh of electricity used. It seems less likely that solar power with battery back up will be viable for high consumers in the foreseeable future.

 
New solar
The value of the grid, now and into the future, is its ability to take power from many generators and supply a numerous and varied group of electricity consumers. When consumption drops in one place it might increase at another; similarly having a large variety of generation on the grid tends to make matching supply to demand easier. If generation, especially renewables such as solar and wind, varies in one place it may well continue at another place – smoothing total generation.

Pumped hydro, with the ability of storing energy when electricity is cheap and generating electricity when demand rises, can only be built in very specific topographic situations; it will always require an extensive power grid. Wind power too requires an area having a good wind resource; so wind power will always require a grid. A similar argument applies to conventional hydro power. These values of the grid will remain.

 

Electric cars

By mid 2014 electric cars had gone from being a novelty that might or might not have had a future to having a small, but fast growing, segment of the new car market. Electric cars have very high capacity batteries.

It is quite feasible for the owners of electric cars to buy electricity at low prices when it is plentiful and sell it back to the power grid at peak consumption periods. The energy retailers do not yet cater for this, but it would be foolish if this potential was neglected. It would benefit both the owners of electric cars and could reduce the costs of running and maintaining the power grid.

Of course it would also be possible to use the capacity of the car batteries to help in the running of a home that is disconnected from the power grid.

It seems likely that gas-fired power generation, with its ability to ramp-up or down quickly to follow demand, will remain valuable for some years. For the sake of greenhouse emissions it should be minimised.

Coal-fired power stations, not being well suited to a generation rate that can follow a varying load, will not find an easy place in this grid. Nuclear, like coal, is most cost effective running at a steady rate; it is also too expensive to be economically competitive, and it is very unpopular.

So, to stick my neck out, I suspect that storage of electricity will remain sufficiently expensive to discourage most power users from leaving the grid. However, an increasing amount of storage, to fill in the gaps between supply and demand, will be needed as we move toward more renewables.

Dual use of solar PV panels, to provide roofing, shade, to reduce evaporation from water storages, and other uses will increase as the price continues to fall.

The use of coal for generation will decrease; it is inflexible and polluting. Power from new coal-fired plants is, or will in the near future be, more expensive than wind and solar. The big regional grids will remain to supply (relatively expensive) electricity 24/7, but micro-grids powered by cheaper solar PV will compete in places. Gas-fired generators will continue to be used to fill the gaps in supply.

From a purely personal point of view I would hope to see storage in pumped hydro or compressed air rather than in batteries because of the consumption and waste involved in making and replacing batteries.






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Jamestown: distinctive features
Shire to go solar?
Where will it end?




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