This week's big questions: What is the most effective way of improving prison? Are free schools a dangerous experiment?

What would be the single most effective way to improve the prison system?

The UK has the highest prison population per capita in western Europe. Crime has been falling rapidly in England and Wales and yet our prison population has doubled over the past 20 years. That needs to be reversed. Some 53 per cent of women in prison have been physically, emotionally or sexually abused as children, have a greater tendency to have mental disorders and drug addiction and are more likely to have no qualifications whatsoever. It has been estimated that only some 3 per cent of women prisoners are a threat to society and alternatives to prison, such as community service, are much less costly and tend to reduce re-offending.

What was the most striking lesson from your time behind bars?

The sheer humanity of women towards other women. Big prisons in particular are not perfect institutions by any means and can be chaotic and frightening, but there was huge solidarity that allowed women to survive what would otherwise have been an unbearable situation. The stark statistic is that, although only some 5 per cent of the prison population, women account for around a third of all instances of self-harm in prison. As an economist I felt shocked at the sheer waste of money and time in sending so many women to prison who did not need to be there. They were victims as well as offenders and needed help, education and employment to stand on their own two feet and not to offend again.

What is the answer to ever-rising energy costs – a bill freeze, a windfall tax or more insulation?

Of course more insulation would help, as would a proper understanding of what green obligations are doing to energy prices. But in the meantime more competition is needed as energy companies have become quasi-monopolies since privatisation. Freezing prices may be double-edged as wholesale prices can come down while prices would be frozen at the wrong, high level. The energy regulator and the Office of Fair Trading should monitor the market and if abuses are found should intervene and impose penalties. Above all we need a joined up European energy policy, but that implies co-operating with the EU instead of turning all relations with Europe into a zero-sum confrontation.

Should Britain have nuclear power stations at any cost?

It is clear that the world, apart from China, is getting more and more uneasy about nuclear power. Angela Merkel has said Germany will be non-nuclear soon and a majority of EU nations now reject it. Cost over-runs in new nuclear build in France have been a problem and the Fukushima incident has led to the first public questioning of nuclear safety at a senior level in the energy industry across the Channel. That said, wind and solar power can never provide secure, guaranteed energy and it remains to be seen whether shale gas will be the miracle solution. We still need an energy mix, but it is clear that we can’t have nuclear without a costly subsidy, paid for by the consumer or the taxpayer. There’s a danger rising energy costs might make UK production uneconomic compared to other countries.

Does it matter that the Co-op Bank is now controlled by hedge funds?

There was no choice in the end as the Co-op Bank’s weaknesses were exposed when it tried to buy the Lloyds Bank branches. An ethical stance is to be encouraged but this should be the case for all banks as the PPI and Libor scandals demonstrate. At the same time financial institutions are custodians of our money and should focus on that core business. We have had to transfer far too much taxpayers’ money to banks and they are still trying to improve their balance sheets. If we end up with a well-capitalised bank able to lend to SMEs and individuals and competing with the big five banks that would be a bonus.

Are free schools a dangerous experiment or a welcome addition to the education system?

I now look at my four grandchildren and worry about their education. Some free schools seem to add value and quality to education and some seem a bit dubious. Are we to condemn all state schools because some have poor outcomes? Academies and free schools are at least helping to add to the country’s education mix and we need more technology schools so our children can find work in the future economy. It makes no sense to reduce the independence of these schools or impose restrictions on the types of teachers they can use if the outcomes are in general good ones and the parents love them.

The euro crisis has gone quiet. Is it over?

It is not over although there are signs of corners being turned. But the debt problems, particularly in the periphery countries, remain and growth is unlikely to be fast enough to make a serious dent. And too many banks with too many bad loans still need taxpayers’ help – including in the UK. The question of the UK staying in the EU has not been resolved. So some sort of a crisis in Europe is ever-present – but was it not always thus?

Vicky Pryce’s book ‘Prisonomics’ is published by Biteback Publishing. Her updated book on the eurozone crisis, ‘Greekonomics’, is being published by Biteback next month