A Labour government would carry out the biggest shake-up of vocational education for a generation to create a "gold standard" qualification to stand alongside the A-level for the 50% of young people who do not go to university, Ed Miliband is set to say.

The Technical Baccalaureate - or TechBacc - would be awarded at 18 to youngsters who complete a programme of work experience, school-based vocational training and academic courses in English and Maths. It would be coupled with a major boost in apprenticeships to provide a pathway to success for the "forgotten 50%" whose needs have been neglected by successive governments, the Labour leader will say.

In a highly personal keynote speech to the Labour conference in Manchester, Mr Miliband will draw on his own memories of comprehensive schooling in north London and speak about classmates failed by the education system because they were not suited to academic exams and university.

"For years and years, our party has focused on those young people who go to university. And that matters," Mr Miliband will say. "But it's time now to focus on those who don't go to university. The young people who are too often the forgotten 50%. We cannot succeed if we can have an education system which only works for half the country."

And he will add: "In the 21st century everyone should be doing some form of education up to 18, not 16. That gives us the chance and the obligation to develop a new system from 14 to 18, in particular, for vocational qualifications. I want a curriculum that is rigorous and relevant with English and Maths up to 18, not 16, culminating in a new technical baccalaureate at 18 based on gold standard qualifications."

Under Labour's plans, businesses would be given control of the £1 billion-a-year Government funding for apprenticeships, coming together in regional or sectoral groups to buy the training they need. The civil service would introduce a fast track route for apprentices similar to the one already in place for graduates, and Government contracts would be awarded on the condition that the firms involved are providing apprenticeships.

Mr Miliband will seek to draw a contrast between his TechBacc plan and the EBacc qualification proposed by Education Secretary Michael Gove, which Labour believes threatens to revive two-tier academic exams at 16. Arguing that EBaccs will replicate the old system of O-levels and CSEs which "just wrote a whole set of people off", Mr Miliband will say: "We don't want to go back to that."

Mr Miliband was dealt a blow ahead of his speech after an opinion poll found just two in 10 people believed he would make a good prime minister.

The poll also cast doubt on the economic credibility of Mr Miliband and shadow chancellor Ed Balls, with only 24% saying they trust the pair to make the right economic decisions. The ComRes survey for the Independent showed just 22% of people believed Mr Miliband would make a good prime minister.

Shadow business secretary Chuka Umunna, tipped as a potential successor to the Labour leader, dismissed the poll's findings. He told the Press Association: "I think the polls that matter are the real polls when people cast their votes. Under Ed Miliband's leadership we have won almost every single parliamentary by-election there has been this Parliament."