* take nothing for granted    
Unless otherwise indicated all photos © Richard McKie 2005 - 2021

Who is Online

We have 140 guests and no members online

Article Index

 

 

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.

 


    Have you read this???     -  this content changes with each opening of a menu item


Travel

Egypt, Syria and Jordan

 

 

 

In October 2010 we travelled to three countries in the Middle East: Egypt; Syria and Jordan. While in Egypt we took a Nile cruise, effectively an organised tour package complete with guide, but otherwise we travelled independently: by cab; rental car (in Jordan); bus; train and plane.

On the way there we had stopovers in London and Budapest to visit friends.

The impact on me was to reassert the depth, complexity and colour of this seminal part of our history and civilisation. In particular this is the cauldron in which Judaism, Christianity and Islam were created, together with much of our science, language and mathematics.

Read more ...

Fiction, Recollections & News

Christmas 1935

 

When I first saw this colourized image of Christmas Shopping in Pitt St in Sydney in December 1935, on Facebook  (source: History of Australia Resources).

I was surprised. Conventional history has it that this was in the middle of the Great Depression. Yet the people look well-dressed (perhaps over-dressed - it is mid-summer) and prosperous. Mad dogs and Englishmen?

 

 

So, I did a bit of research. 

It turns out that they spent a lot more of their income on clothes than we do (see below).

Read more ...

Opinions and Philosophy

Conspiracy

 

 

 

Social Media taps into that fundamental human need to gossip.  Indeed some anthropologists attribute the development of our large and complex brains to imagination, story telling and persuasion. Thus the 'Cloud' is a like a cumulonimbus in which a hail of imaginative nonsense, misinformation and 'false news' circulates before falling to earth to smash someone's window or dent their car: or ending in tears of another sort; or simply evaporating.

Among this nonsense are many conspiracy theories. 

 

For example, at the moment, we are told by some that the new 5G mobile network has, variously, caused the Coronavirus pandemic or is wilting trees, despite not yet being installed where the trees have allegedly wilted, presumably in anticipation. Of more concern is the claim by some that the Covid-19 virus was deliberately manufactured in a laboratory somewhere and released in China. 

Read more ...

Terms of Use                                           Copyright