Resource efficiency and renewable technologies will be essential drivers for growth in the years ahead, according to former US president Bill Clinton

Speaking at the Re|Source 2012 conference in Oxford, Clinton told 250 business leaders and government officials that economic growth should not be predicated on the use of natural resources.

He also urged policymakers to prioritise the management of finite natural resources and to focus investment on renewables and energy efficiency.

He said that while 870 jobs are created for every $1 billion invested in building a coal-fired power station, spending the same amount on retrofitting buildings with energy saving measures would create 7,000 new jobs.

Clinton’s speech ended the two-day event, which had also heard from David Nabarro, the UN’s special representative on food security and nutrition. He warned that resource scarcity could lead to conflict.

“We know clearly that inequalities around food, water and energy wealth do create wars,” said Nabarro. “Unless they can be dealt with, the future for all of us is going to be very difficult.”

Nabarro also forecast that the Rio+20 summit is likely to be the last time 190 world leaders would assemble to sort out global environmental problems, saying that partnerships involving governments, businesses and civil society would be the best way of providing solutions in future.

Like Clinton, Nobel laureate Amartya Sen advised governments to do more to encourage investment in renewable energy by offering greater incentives.

Meanwhile, Poppy Allonby, managing director at Blackrock Investment UK, claimed the reasons for the failure of low-carbon technology to attract investment were poor policy and an ineffective regulatory framework. She said the past 12 months have been extremely difficult for investors in renewable technologies.

Professor Chris Llewellyn Smith pointed out that the fossil fuel industry receives $400 billion in subsidies each year, while Lord Mandelson said that no subsidy should last forever because while most support systems are created with good intentions they can have unintended negative consequences later on.

Peter Brabeck-Letmathe, chair of Nestlé, was highly critical of biofuels, claiming that using land and water that would otherwise have been used to grow crops for consumption had helped push the cost of food higher.

“The time of cheap food prices is over. We are now in a new world with a completely different level of food prices, and with high volatility, because of the direct link with fuel,” he warned. “Biofuels are only feasible because of the high subsidies they receive – $25 billion so far.”