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As the energy is essentially free, renewable electricity costs, like those of nuclear electricity, are almost entirely dependent on the up-front construction costs and the method of financing these.  Minimising the initial investment, relative to the expected energy yield, is critical to commercial viability.  But revenue is also dependent on when, and where, the energy can be delivered to meet the demand patterns of energy consumers.

For example, if it requires four times the capital investment in equipment to extract one megawatt hour (1 MWh) of useable electricity from sunlight, as compared to extracting it from wind, engineers need to find ways of quartering the cost of solar capture and conversion equipment; or increasing the energy converted to electricity fourfold; to make solar directly competitive.

Similarly if a technology produces electricity when consumers don’t want it; or produces it so far from the consumer that most of it is lost in transmission; then the revenue available will be proportionately less than a similar investment that better matches demand; or is located close to where it is consumed.

 

In most developed nations, including Australia, electricity is a traded product with the market price fluctuating from hour to hour; day to day; season to season; in five minute intervals, according to supply and demand.

 

Without government intervention in the market, supply and demand determines the return that is available to an investment; while the engineering solution and qualities of the resource determine the energy that a particular investment can theoretically deliver.

 

Before intervention, current renewable technologies, with the exception of hydro- electricity, are substantially less competitive, in terms of return on investment, than fossil fuels or nuclear electricity.  It follows that wherever alternatives are in use there are other factors at play: such as the cost or practicality of a grid connection; or a government intervention in support of renewables.

In Australian electricity markets this intervention takes the form of Renewable Energy Certificates (RECs) described later. Other governments have other instruments such as cap and trade carbon reduction schemes; carbon taxes; energy buy-back schemes; and tax breaks; to achieve similar ends.

 

In Australia grid losses are of particular concern. Australia’s population of just over 21 million is highly concentrated in a few large cities; just eight cities accounting for over 70% of the population. The largest Sydney; Melbourne; Brisbane; Perth and Adelaide account for 63% but are separated by distances of between 670 and 3,600 km; ‘as the crow flies’. This is similar to the continental USA and a substantially greater area than the entire EEC.

Transmitting electricity over such distances results in significant losses.  The market price received by a generator is therefore influenced by transmission costs and the point on the grid into which electricity generated is injected.  A renewable energy project remote from the points of high demand will receive a lower price than one adjacent. 

Very high voltage DC (HVDC) technology can reduce the net grid loss problem over long distances, and this is in use for links to Tasmania and South Australia, but it adds at least two costly voltage translations and the additional capital cost, together with the low capacity factor of wind and solar, precludes its use in most, if not all renewables dedicated situations.

 

Even with the present substantial and probably increasing REC cross-subsidies from electricity consumers, transmission factors limit the economic distance an exploitable wind or solar resource can be from the main electricity grid and electricity consumers.

 

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Travel

Spain and Portugal

 

 

Spain is in the news.

Spain has now become the fourth Eurozone country, after Greece, Ireland and Portugal, to get bailout funds in the growing crisis gripping the Euro.

Unemployment is high and services are being cut to reduce debt and bring budgets into balance.  Some economists doubt this is possible within the context of a single currency shared with Germany and France. There have been violent but futile street demonstrations.

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Fiction, Recollections & News

Merry Christmas

 

 

 

As Tim Minchin sings in White Wine in the Sun [turn on your sound...] Christmas is a time for family.  Last year our family got bigger.  Tilda Charlotte was born in Germany. This Christmas she is walking and sort of talking (a couple of German words at least).  So the lyrics:

And if my baby girl
When you're twenty-one or thirty-one
And Christmas comes around
And you find yourself nine thousand miles from home
You'll know what ever comes
Your brothers and sisters and me and your mum
Will be waiting for you in the sun
When Christmas comes
Your brothers and sisters, your aunts and your uncles
Your grandparents, cousins and me and your mum
We'll be waiting for you in the sun
Drinking white wine in the sun Darling, whenever you come
We'll be waiting for you in the sun
Drinking white wine in the sun
Waiting for you in the sun Darling, when Christmas comes
We'll be waiting for you in the sun
Waiting
  

have a special meaning this year:  I really like Christmas - It's sentimental, I know.

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Opinions and Philosophy

Climate Change - a Myth?

 

 

Recently, an increasing number of friends and acquaintances has told me that Climate Change is a myth.  

Obviously they are talking about 'Anthropogenic Global Warming', not disclaiming actual changes to the climate.  

We don't need climate scientists to tell us that the climate changes. Our own experience is sufficient to be quite sure of that. 

During my lifetime the climate has been anything but constant.  Else what is drought relief about?  And the ski seasons have definitely been variable. 

In the longer term we all have to rely on others. For example on scientists who have themselves examined ice cores or tree rings or sea level records or other physical evidence that can be dated. 

So I'm prepared to believe the scientists who have determined sea levels showing that fourteen or fifteen thousand years ago a hypothetical Australian could walk from Tasmania to New Guinea or an Irishman all the way to Java.

 

Changing sea levels during the past 20,000 years
 Source Wikipedia: Early Human Migration & Sea Level change

 

This rise has not stopped.  During my lifetime the average sea level in Sydney Harbour has risen by nearly a foot, in keeping with long term trends.  More water in the Harbour on average obviously has temperature and therefore microclimate implications.  There are thousands of well documented examples of changes like this that have climate impacts.

But like the tides there is great variability that masks the underlying trends.   For example 2014 was a record warm year in Sydney.  But in mid 2015 we were going through the longest cold spell in 45 years.  It snowed in Queensland!

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