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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

The United States of America – East Coast

 

 

In the late seventies I lived and worked in New York.  My job took me all around the United States and Canada.  So I like to go back occasionally; the last time being a couple of years ago with my soon to be wife Wendy.  She had never been to New York so I worked up an itinerary to show her the highlights in just a few days.  We also decided to drive to Washington DC and Boston. 

 

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Fiction, Recollections & News

Are we the same person we once were?

 

 

 

I was initially motivated to write this cautionary note by the controversy surrounding the United States Senate hearing into the appointment of Judge Brett Kavanaugh to the US Supreme Court that was briefly called into question by Dr Christine Blasey Ford's testimony that Kavanaugh sexually assaulted her when they were both in their teens.

Kavanaugh is but one of many men who have come to the attention of the '#MeToo' movement, some of whom are now cooling their heels in jail.

Like the Kavanaugh example number of these cases, as reported in the media, seem to rely on someone's memory of events long past.  Yet as I will argue below after a decade or so our memories are anything but reliable.  After that time we should be respecting the accused's legal right to be presumed innocent, unless there is contemporary immutable evidence (diaries photographs and so on) or a number of non-colluding witnesses or others who have suffered a similar assault. 

Now in the news another high profile person has been convicted of historical sexual assault.  Cardinal George Pell has appealed his conviction on several charges relating to historical paedophilia.

There is just one accuser, the alleged victim.  A second alleged victim took his own life some time ago. The case was heard twice and in total 22 of the 24 jurors decided in favour of the alleged victim, despite the best defence money could buy.  Yet, as with the '#MeToo' movement in respect of powerful men, there is currently worldwide revulsion (see my Ireland Travel Notes) at sexual crimes committed within the Roman Catholic Church, such that a Cardinal is likely to be disbelieved, just as at one time a choir boy's accusations against a bishop or a priest would have been, and were, dismissed.

Both trials were held in closed court and the proceedings are secret so we have no knowledge of any supporting evidence. We do know that the two alleged victims were members of the Cathedral Choir and at least one other ex-choir boy also gave evidence. So justice may have been served. 

Yet I'm just a little concerned about the historical nature of the charges.  How reliable is anyone's memory? 

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Opinions and Philosophy

The Meaning of Life

 

 

This essay is most of all about understanding; what we can know and what we think we do know. It is an outline originally written for my children and I have tried to avoid jargon or to assume the reader's in-depth familiarity with any of the subjects I touch on. I began it in 1997 when my youngest was still a small child and parts are still written in language I used with her then. I hope this makes it clear and easy to understand for my children and anyone else.

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