A second-hand ambulance has been converted into a place where sex workers can meet their clients in Copenhagen. The aim is to help people at risk of violence and exploitation and it is the latest in a long list of ideas by a Danish social entrepreneur.

Michael Lodberg Olsen invites me into an old ambulance, long out of service.

"So what happens in here?" I ask.

"Sex," he quickly answers, eyes flashing with laughter.

It's not very inviting as I step inside. It still looks very medical - grey walls, blue seat. And it's cold - it's -1C and snowing outside.

But this old ambulance - called "Sexelance" - is a safe space for Copenhagen's sex workers. They can bring clients here with the knowledge that volunteers are around to step in if things get ugly.

And the stats show that often things do.

"Sex workers in Denmark are violated or threatened 45% of the time, but at a brothel this figure is only 3%," Michael says, using figures from the Danish National Centre for Social Research.

Image caption Social entrepreneur Michael Lodberg Olsen has started numerous projects

It's the sex workers plying their trade on the streets - who cannot afford to use an illegal brothel - that Michael aims to help. Sexelance is free to use, as while prostitution has been legal in Denmark since 1999, it is still against the law for sex workers to rent rooms or hire any help for their business.

As well as human volunteers for protection, inside there is a notice on the wall saying police will be called at the first sign of violence and another encouraging sex workers to get in contact if they are victims of human trafficking.

And there are other items to help too. Wipes for cleaning after sex, three condom options, lube, even a heater run on electricity from a generator outside. All these suggestions came straight from sex workers.

"These people are my neighbours and friends so I listen to them, they have the best ideas for what they need," Michael says. For instance, the sex workers told him they often get sore knees.

"So we came up with this", he says, waving a rainbow-coloured chunk of polystyrene at me.

When Sexelance started operating in November 2016, Michael wasn't sure it would work. People were initially reluctant to use it, particularly clients. But now it has been used 45 times and Michael says people are becoming more comfortable with the idea.

"If the sex workers think it's a good idea then they will ask the customers to come here and tell them, 'It's a safe place, there are all the condoms we need, and there's heat!'" Michael laughs.

He offers his ideas with a light, humorous touch, like his description of how sex workers would like to "pimp" up the ambulance with curtains, mirrors and red carpet on the walls.

But in his actions Michael is entirely serious. It's not the first time he has used an old ambulance to help what he calls Copenhagen's "street minorities", and his first initiative got people listening.

It was similar to Sexelance - a repurposed old ambulance, this time a German one from the 1990s called Fixelance. It provided drug addicts with a space to take drugs, with an on-site doctor and nurse, equipped with clean needles and Naxalone, an antidote for heroin overdose.

Unlike Sexelance, uptake for this one was quick. Eight people used it to inject heroin in the first three hours.

Also unlike Sexelance, Michael encountered a lot of resistance from the authorities. Two separate plans for permanent drug rooms were stopped by the authorities.

But it went ahead in 2011 with 100 volunteers involved and despite nerves on the first day, Fixelance achieved what Michael wanted.

Image caption Fixelance was used to target areas known by drug users

It spurred the government to change Danish drug policy in 2012 and there are now five permanent facilities - "fixerums" or "fix rooms" - across Denmark. One based in Copenhagen is the largest in the world and the original Fixelance ambulance is now exhibited at the National Museum of Denmark.

There have been no fatal overdoses reported in any organised "fix room" anywhere the world.

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As well as the two ambulance schemes, Michael created a magazine called Illegal! which hit the streets in Copenhagen in 2013. It's sold by drug addicts and in fact the explicit aim of the magazine, produced by volunteers, is to provide money to the addicts so that they can get their fix. It's an idea that again met resistance from some citizens, Michael says.

His aim with the magazine is to challenge what he says are people's preconceived ideas that drug users are just people who should be locked up for their habit.

"The consequences of our current political system is that drug users often have to steal to fund their habits," he says. "We are trying to make these people, who have addictions, less criminal. Yes, they may buy drugs with the money but that is real life."

Image copyright Alamy

The aim is to give the sellers more dignity by providing a magazine that people actually want to buy. The production quality therefore is very high, the art all original and the sellers take $2.50 (£2) commission.

Rikke Lauritzen from the municipality in Copenhagen says Illegal! is doing an important job on the streets of of the city.

"It's naive to think people will stop using drugs. What's important is that the authorities offer help and treatment for those who want to stop using. The only way we can do that is to see the human, not the addiction," she said.

And Copenhagen police support her stance saying they do not have a problem with the magazine, as long as it is legal.

Illegal! was sold in east London too for the first time two years ago, and there are plans for a bigger rollout in the UK's capital. But the Metropolitan Police said they "discourage anyone from giving money to someone that states they want to use it to commit crime."

And if he wasn't busy enough, Michael has also dedicated his time to making life easier for Copenhagen's bottle collectors.

There is a return scheme in most cities in Denmark where deposits are paid on bottles and cans to encourage recycling - consumers return the containers to supermarkets to collect their money.

Like in many places with container deposit schemes, homeless people and struggling pensioners rummage through through bins to get cans and bottles that others - who don't care about collecting the small deposit - have thrown away. Michael's simple idea was to place shelves on bins. They're now on 1,000 bins out of 5,000 in Copenhagen and the idea has spread to four other cities in Denmark.

Again, this idea is to give dignity back to Copenhagen's "street minorities", Michael explains. "Instead of thinking of these people as poor or homeless, we think of them as environmental workers who do an important job," he says.

So far there hasn't been any negative reaction to Sexelance - the police are engaging with Michael to suggest the best places to park it - and he hopes ultimately that the idea will go the same way as Fixelance, a permanent facility manned by doctors and nurses for Copenhagen's sex workers.

"It's about safety first and foremost, but it's also about better health and dignity," Michael says. "You can see how cold it is outside, and think normally these women are seeing clients on a bench, or in a car. It's not right that they should be out there with no support."

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