Alan Parkinson accused him of pushing his own barrow because he is director of the Centre for Sustainable Energy Systems at ANU. This barrow, however, is well worth pushing given the undoubted warming of the climate over the past 50 years. The cost of dealing with the impact of climate change was not factored into the cost of electricity etc until the previous government made a somewhat muddled attempt to do so, and which the current one wishes to wind back.

J. McKerral asserts that the economics are wrong because the capacity factor (the average fraction of time that the generator puts out electricity) has not been taken into account. This is not so. In the Bureau of Resources and Energy Economics (BREE) report, Australian Energy Technology Assessment, referred to by Professor Blakers, the costs of producing electricity from 40 fossil and renewable generating technologies (including nuclear) are assessed with or without carbon capture and storage. The economic factors in the BREE model do indeed include the capacity factor. This is set at 83 per cent for fossil energy, while for renewables it is 21-26 per cent. This report concludes that renewables, particularly wind, will be cost effective, as would nuclear.

Of course, economic models can rightly be viewed with suspicion as to their precision, but the broad picture they paint should be noted.

David Williams, Watson

Daniel Bennett's comments on light rail (''Light rail brings a bold new vision for our city'', TImes2, March 24, p5) misses the point on one important fact, it needs customers to make it pay. Even the light rail in Sydney is uneconomic much of the time. How will Canberra be able to afford the proposed light rail from Civic when the population is not there to support it? Is this to be another white elephant?

John Bury, Macquarie

First Shane Rattenbury claimed a gold-plated tram was necessary to do something about Northbourne Avenue traffic averaging 20km/h at peak hour. A sad joke. Now, in proposing legislation to help them ride roughshod over planning/development constraints when they feel like it, we're told that this city's giant green elephant is in fact urgently needed to kick-start an ailing building sector (''Push on light rail, mental health'', March 20, p1). To distract, they lumped building the tram in with building Canberra's long-overdue mental health facility. You remember, the one that a succession of Labor governments refused/forgot to build over the past decade or two.

Let's spend the $1 billion slated for the big, green elephant on cutting prices for new house blocks and lower stamp duties.

That'd encourage building, and perhaps that proposed city-central stadium. But they'd lack the tram's grand, half-baked, green symbolism. So they won't do it.

Michael Jordan, Gowrie

I've just received my renewal notice for third party car insurance. I applauded the government when it opened NRMA's monopoly to more competition. So, what has been the effect?

According to my notice, we now have four players in the market (GIO, APIA and AAMI being the additions) so you would expect some competitive forces to come into play. Hence my dismay on reading their premiums to be in the very narrow range of $579 to $599, which, combined with the government fee, produces a total cost range of $838 to $858.

I've checked what it would cost in NSW and discovered my car could be insured there for $100 to $300 less! There are a lot more insurers in the state, which would bring down prices. On the other hand, I would have thought the risks are higher in NSW.

I am left with the uncomfortable thought that we have moved from a monopoly to an oligopoly.

There does not need to be collusion among the four. The newcomers just leverage off the incumbent to the joy of their shareholders. Because of our high average incomes, we remain treated like mugs. The government should not rest on its perceived laurels.

Geoff Clark, Narrabundah

Last November I had published a book, Australia's Secret War: How Unionists Sabotaged our Troops in World War II (Quadrant Books, Sydney). It deals with instances of strikes and sabotage in strategic industries, including wharves, dockyards, coalfields and munitions plants.

I received a great deal of information from ex-servicemen, unionists and others, and interest has been such that the publishers inform me that it is going into a fourth printing after only three months.

This has encouraged me to try to compile a second volume, probably taking in the Korean and Vietnam wars, as well as World War II, and I therefore ask any ex-service personnel and others with information in this area, whether from first-hand experience, unit histories, family stories, etc, to contact me, giving their name, branch of service, rank and serial number with an account of the relevant incident. All material printed will be acknowledged.

(Dr) Hal G.P. Colebatch, Nedlands, WA (halcolebatch@hotmail.com)

David Jenkins (letters, March 22) raises the valid if predictable point that people have been executed for killings they did not commit. But in an unpublished letter, I drew a distinction between ''beyond reasonable doubt:'' Martin Bryant, Ivan Milat, the killers of Mrs Morse and Anita Cobby in NSW, Knight and Bayley in Victoria and Cowan in Queensland, to name a few.

We are a ''civilised'' society - on other issues as Jenkins states, a questionable claim - but here suffice to say our superior attitude is at the expense of someone else's loved one, because some of these offenders have struck before and our belated response is to tighten the law, like bolting horses and stable doors.

Apart from the pointlessness of keeping such killers in prison, there is the constant threat they might be released again by deluded parole boards and naive supporters of rehabilitation, and usually only prevented from freedom by community outrage.

People who oppose the death penalty affirm the sanctity of life, so presumably they also oppose death with dignity for our aged and sick where support sits at more than 80 per cent. Now that I regard as barbaric.

Greg Cornwell, Yarralumla

It's becoming increasingly clear that we have two governments running Australia. The first is the one composed of elected politicians chosen by voters, plus the hard-working public servants who are asked to carry out the policies of whichever party is in power. That is the government whose activities are mostly open to public and media scrutiny.

But we have a second, secret and dark government, one that operates in the deepest shadows. It is populated by an assortment of wheeler-dealers, shonks, spivs, self-serving lobbyists, former politicians looking for a nice post-career earner, and a few current politicians unsatisfied with the generous salaries and benefits they receive from the public purse. They consider ordinary working Australians to be suckers for grinding away at their jobs year after year, hoping to lay enough aside for at least a life of genteel poverty in their old age.

This shadow government tries to remain hidden in a web of dodgy legal entities constructed by equally dodgy lawyers and accountants; their main enterprise is redirecting our taxes away from the public good and into their own pockets. These easy money boys (interesting how they are almost exclusively male) come from both sides of politics in what must be one of the last truly bipartisan endeavours operating. The only principle under which they operate is greed.

It is only when bodies such as ICAC and courageous journalists such as Kate McClymont get to work that light is shed on the nefarious activities happening in the sewers beneath public life in Australia. We have barely scratched the surface of corruption, and owe them an enormous debt of gratitude.

Steve Ellis, Hackett

Tony Abbott has called on nations in our region to ''share the burden'' of accepting asylum seekers from Manus Island.

These asylum seekers only want a peaceful life and an opportunity to contribute to Australia; how are they a burden? I have known and worked with a number of refugees from Vietnam who have either made a successful career, or in one case set up a Vietnamese restaurant that employed young Australians.

Are they a burden? Asylum seekers present us with an opportunity; and any Australian government is derelict in its duty if it doesn't grab this opportunity with both hands. We need these people to contribute to our economy and enrich our society in the same manner that previous waves of immigrants and refugees have done. The government is letting us down badly if it doesn't welcome refugees with open arms.

David Hicks, Holt

The near-term demise of Australia's car industry; the uncomfortable outlook for manufacturing generally; uncertain economic health for future federal budgets; nearly 800,000 receiving government welfare, and no improvement on closing the indigenous gap warrant increasing the GST by one percentage point. This would generate about $4.6 billion on the current base, and $5.5 billion on a comprehensive base. The privatisation of Medibank would realise about $4 billion. Additional federal government incomes of this order for state distribution are needed as our economy enters economic whitewater.

Colliss Parrett, Barton

So, the Assistant Treasurer Arthur Sinodinos has ''stepped-aside'' pending completion of investigations by ICAC into the activities of Australian Water Holdings (''John Howard's man falls from grace as Arthur Sinodinos steps down'', canberratimes.com.au, March 24).

I'm not a lawyer and maybe I simply don't get it, but I don't understand how ICAC can make findings in respect of Mr Sinodinos, given that he was not and is not a public official in NSW. At the same time, given allegations that Sydney Water was defrauded by Australian Water Holdings, why hasn't the NSW Police fraud squad been called in to investigate? And where is ASIC?

Once again it would seem that there is ''nothing to see here'', simply because those responsible aren't looking!

John Richardson, Wallagoot, NSW

Poor Arthur Sinodinos. You can't get any further backbench than sitting next to Senator Zed Seselja (''Few celebrate this success'', Times2, March 21, p4).

Don Sephton, Greenway

It is tragic that 200-300 people appear to have died as a result of the Malaysian Airlines disappearance. There is rightly widespread coverage in the media because travelling by air is generally safe and aircraft disasters are, fortunately, rare.

The same number died last week in Australia from tobacco related diseases but that does not make news because, unfortunately, 200-300 Australians die every week from the effects of tobacco smoking.

Dr Alan D. Shroot, president, Canberra ASH (Action on Smoking & Health)

A senior citizen crashes into the wall surrounding The Lodge. An accident, a national security breach or an act of pure frustration? Mystery abounds. How has this not happened before? Perhaps it was the subliminal chorus of Bishop, Pine, Brandis, with a chilling South African backing vocal that put this member of the Grey Army over the edge. It could happen to anyone and often does. Though tearing the wall down is positively inspirational, even biblical. ASIO and ASIS will no doubt be mobilised to get to the bottom of this lack of support for far less responsible and compassionate government for all.

Peter Funnell, Farrer

Before we all get carried away thinking the single Newstart allowance has suddenly catapulted to $511 per week (''Age pension, Newstart gap widens'', March 24, p2,) let me point out that the $511 is a fortnightly payment. Those on Newstart are not about to become residents of Fat City any time soon. How they survive on that amount is anyone's guess.

Janet Thomas, Kaleen

Most units built in Canberra in recent years have numerous defects, some even of a structural nature. The Owners Corporation of the ACT has tried for many years to work together with the ACT government to address the bad standard of construction that is particularly evident in blocks of units.

Defects in blocks of units are very costly to rectify. The more units and the more storeys in a block, the higher the rectification costs and the more people are affected by them.

Canberra is subject to seismic tremors (see Marion Leiba, Geoscience Australia, ''Earthquakes in the Canberra region''). There are only three buildings that are seismically safe and they are not residential high rises.

Of greatest concern is the fact that buildings higher than three storeys do not carry the home owner's warranty insurance that is mandated for lower buildings. This leaves the unit owners of buildings higher than three storeys exposed to unscrupulous builders and developers and with construction defects costs that will have to be met by the body corporate.

Until construction standards and the proper warranty insurance are addressed, Canberra is definitely not ready for high rises.

Lydia Frommer, architect and town planner, Lyons

The Canberra Times should be aware that there is a high school in Yass and students will not ''have'' to travel to Canberra (''Yass Catholic students forced to travel to ACT as school closes'', March 21, p1). They may choose to endure the bus ride, but certainly not for the lack of quality at the local government high school. My bet is the NSW government hopes the trip to Canberra is opted for as attempts to move Yass High School into the 21st century following the fire in 2012 failed miserably.

David Ingles, teacher, Yass High, NSW

SCRIVENER SAVINGS

Amid all the recent reports of budget blowouts, it was pleasing to read that the Scrivener Dam anchor bolt project was completed at half the original estimate (''Scrivener anchor bolts replaced'', March 22, p2).

Well done to all the engineers and construction workers involved.

Geoff Nickols, Griffith

THE ABBOTT EFFECT

So, against all the predictions of the so-called experts, South Australia will continue to have a Labor government. I strongly suspect, although it cannot be proved, that the advent of Abbott and his right-wing government, had a lot to do with it.

Vic Adams, Reid

LUXURY BLOCKED

If I could afford at least $1,700,000 (the reserve price) for a luxurious apartment I would expect it to be in a building which presented a facade of luxury living. Why did the producers of The Block choose a building which has the appearance of an abandoned Salvation Army shelter for the homeless ?

Alan Blake, Duffy

LODGE'S WEE PROBLEM

It's one thing to have possum pee drive the PM from The Lodge.

However when a wee hatchback can crash the joint (''Driver escapes serious injury after his car Lodges in PM's wall'', March 23, p3), I suggest security reappraise their priorities.

Linus Cole, Palmerston

CAPITAL PUNISHMENT

I offer the following comment in relation to David Jenkins' statement that ''the ACT has never had capital punishment'' (Letters, March 22).

In fact, when our territory was established a century ago we inherited NSW criminal law, including the death penalty.

However, no executions ever took place in the territory.

Frank Marris, Forrest

CONMEN SHUT OUT

Re Kirsten Lawson's story, ''Warning over gang of door-to-door conmen'' (March 19, p3), I have next to my front door bell a conspicuous notice which reads ''No Door to Door Traders Please'' (courtesy of the ACT Office of Fair Trading), and for good measure, another spelling out ''No door knockers thank you''. They have been effective for the past seven years.

John Milne, Chapman

POLITICS DEMEANING

Politicians seem to think the electorate is easily fooled. But most of the smartest people out here wouldn't demean themselves by going into politics. And it's got nothing to do with monkeys and peanuts.

Barrie Smillie, Duffy

Email: letters.editor@canberratimes.com.au. Send from the message field, not as an attached file. Fax: 6280 2282.Mail: Letters to the Editor, The Canberra Times, PO Box 7155, Canberra Mail Centre, ACT 2610.

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