Minister for Education Batt O'Keeffe certainly generated plenty of headlines last week when he confirmed that he is considering the return of third-level fees as part of a wider review of how the Irish third level system is funded.

At a time when some estimates put the number of university students attending fee paying schools at as high as one in five of the total, supporters argue that the less well off should not be subsidising those who can afford such fees.

Others maintain that the reintroduction of fees for undergraduates would be a hugely retrograde step, and would act as a significant disincentive to many potential students.

But a Sunday Tribune examination of how such a move might work in practice suggests that for a variety of administrative and economic reasons – and regardless of whether one supports such a measure – any decision to reintroduce fees for well off students only may not work.

O'Keeffe was at pains to stress last week that only the better off would be required to pay if the government ultimately decided to bring back fees to help meet the shortfall in funding of the third-level sector.

He told The Irish Times he was embarking on a programme of national debate about the issue and that no decision had been taken about reintroducing fees – or what the threshold would be set at for payment of fees if they were reintroduced.

"We haven't made any decision yet, we're embarking on a national debate but I certainly wouldn't envisage any family on €100,000 a year in joint income having to pay third-level fees and in fact, I would envisage the bar being set much higher than that," he said.

O'Keeffe also acknowledged that middle class families had benefited greatly from the abolition of third-level fees. But both middle class and working class families would not have anything to fear about their reintroduction, he said.

"What I am saying quite clearly is that I would never bring within the band people who can ill-afford to pay. I would rather be looking at people who can afford to pay and there are many millionaires in this country who can afford to pay," he said.

In this context, and assuming that O'Keefe eventually decides to introduce a threshold, the question then becomes: how many people would this capture and how much revenue might this generate? Or, as one letter writer to that paper put it last week, "Who are the middle classes?"

All options are on the table

According to latest income projections supplied to this newspaper by the Revenue Commissioners, there are approximately 131,000 individuals or married couples in the state whose gross income exceeds €100,000 per year.

Of course, not all of these will be the families referred to by O'Keeffe – some will be unmarried or married without children – while even those families who find themselves in this group are by no means certain to have children of third-level going age.

Interestingly, the same figures also reveal that, were the cut-off point to be over €150,000 per year in earnings, this far from homogenous group would shrink to just 47,300.

As a result, the capacity to generate significant income from such high level earners is, to say the least, open to question, with some even suggesting that the amounts involved could be "derisory".

In his media interviews during the week, O'Keeffe also strongly hinted that if he decides to reintroduce fees, this might be achieved via a system based on parental income.

Under such a model, students' eligibility for fees – or indeed fee waivers – would be based on how much their parents earn.

However, a spokesman for O'Keeffe told the Sunday Tribune that it was too early to say which type of approach, if any, might be favoured as "all options are on the table".

The minister's intention, he said, was to stimulate a constructive and wide-ranging national debate on the funding of the third level sector, and to ensure taxpayers' money is being used effectively and efficiently for the benefit of third level students. This is expected to take 18 months to complete.

Student loan system works elsewhere

PD leader Senator Ciaran Cannon has suggested that the state should look to the Australian model of student loans, which has since been copied elsewhere around the world including the UK.

Under this system, now known as HELP, students take out government-sponsored loans which are repaid once they have graduated and start earning a particular annual salary threshold, which is set at A$41,595 (¤24,549) this year.

Yet the lead-in time for this type of a system to start generating loan repayments for the government is considerable, if the experience in Australia is anything to go by.

Information supplied by the Australian Department of Education shows that the average length of time between when a student incurs a debt and when they start paying this back, is around five years.

The average time for full repayment of HELP debts is seven and a half years, the department also reveals.

Were that to be replicated in Ireland, and given the lead-in time for O'Keeffe's review, this indicates that any student loans system introduced here may not become self financing until 2017 at the earliest.

While supporters of such a system note that the government paid out €332m last year alone on free fees, which would cease to be necessary under a new system, clearly at least some of this money may need to be diverted in order to "bankroll" a student loans project.

Other key players in the free fees debate go even further when asked for their views on income thresholds for student fees.

One of the foremost proponents of the reintroduction of third level fees, Prof Ferdinand Von Prondzynski, the influential president of Dublin City University, told this newspaper that any move to make the reintroduction of fees reliant on parental or student income thresholds could defeat the whole purpose of the exercise.

Instead, he argued strongly that any move to reintroduce third level fees should be applied across the board to all students.

In comments which would seem to directly clash with the views of O'Keeffe, he warned that he will be arguing that universities should refuse to oversee any income-based fees system, as it could be "impossible to administer".

Setting an income threshold of €100,000 or above could lead to a situation whereby "nobody of any significance" would be paying the fees, meaning it would "not be a system worth having at all", he said.

"I will be resisting any threshold," he revealed. "I would certainly argue that we should not go along with plans to administer an income based system. If you look at some of the minister's statements this week, the amount of income generated would be very small. The question is then, 'why bother?' It is possible that the cost of employing people to administer the scheme would be greater than the revenue generated."

Grants for those who need them

Another risk, of course, is that none of the money generated will actually serve the stated purpose of raising the status of our cash strapped universities who, others point out, can often afford to pay their senior staff hefty salaries and bonuses.

For his part, Von Prondzynski argues that funding levels for the third level sector – which has been told to seek salary cuts of 3% this year – should be guaranteed to remain at current levels, and should be index linked in the future.

Any additional funding, such as that generated from student fees, should then be "ringfenced" to ensure the sector directly benefits from this money, he says.

Von Prondzynski personally favours a mix of grants for those who need them most, as well as a mix of both public and private loans for students if necessary.

Any income generated from student fees should be used by colleges to introduce significant supports and scholarships for students from poorer backgrounds, he said.

"Most of the people benefiting from free fees are the middle classes, and most of the money has gone to the better off. We need to target the money much more at the less well off," he said.

"I certainly would accept in our case that DCU should make some of the money from fees available directly to students in need of support."

So, where does this all leave us? Clearly, the issue of reintroducing third level fees is firmly back on the political agenda.

But when it comes to formulating specific public policy on the issue, the devil, it appears, may well be in the detail.