Stockholm isn't surrounded by nature - it is nature. About 40 percent of the city's area consists of green space, and the 14 islands offer 30 public beaches and eight protected natural reserves. So even though Stockholm is growing, it remains very green.
And the city is working hard to keep it that way. Several years ago, Stockholm became the first city in the world to win the European Green Capital Award, and in 2015 Stockholm was one of just 11 global cities to meet all the requirements of the Compact of Mayos, an ambitious action plan to fight climate change.
But that's not enough.
"Our goal is for the City of Stockholm to be fossil fuel free by 2040," Mayor Karin Winngård has said. "Stockholm is already an acknowledged global climate leader, but we are fully aware that the city must excel in all aspects in order to reach our goal."
And sustainability and the environment are not just the concern of mayors and other politicians. In Stockholm, it's personal – and Stockholm’s tech community is working hard to do its part.
In fact, dozens of ground-breaking Stockholm tech companies are taking on the world’s biggest problems – aiming to change the way energy is produced, stored, and consumed – and make the world a better place.
Solar energy without the sun
One such innovation is the EnergyHub system developed by Ferroamp, a Stockholm-based tech company founded in 2010 with a vision of building a more effective solar inverter technology. The system boosts output and increases flexibility in solar power installations, by capturing and storing solar energy more effectively.
“In the middle of the day when we have more production from the solar panels than is consumed in the building, instead of sending the energy to the grid, we can send it to the Energy Storage system,” says Mats Karlström, Ferroamp’s VP of Sales and Marketing.
Ferroamp’s system also features Solar String Optimizers (SSO) that boost voltage from each solar panel to a fixed output level.
“Because we have a fixed output, it doesn’t matter how many panels are connected or how the sun hits the panels. Thanks to the SSO, we can connect all solar panels to the same two wires, allowing for easier and cheaper installations,” Mats explains.
What does this all mean for solar energy? Well, quite a lot – particularly if you live in Sweden…
“This means that the hardware [solar panels] you invest in also works when the sun doesn’t shine,” explains Mats. “The traditional solar inverter only works when the sun shines, but in this case, EnergyHub continues at night and all through the winter.”
Stockholm may not seem like the optimal location for a solar energy company, but Mats is adamant that being based in the Swedish capital is only a positive for Ferroamp.
“It’s one of the toughest markets to develop a technology like ours, if you look at it from a customer perspective, because the energy prices are very low in Sweden,” he says. “We have to think outside the box and innovate completely new solutions.”
Doing the wave
Being based in Stockholm is also part of the success of CorPower Ocean, another Stockholm company breaking ground in the sustainable energy industry by harnessing the power of ocean waves.
“It’s quite telling that one of the most prominent companies in wave power is situated in Stockholm where there is very little wave energy,” CorPower Ocean Commercial Director Anders Jansson explains. “Even though we don’t have the resource next door; we still have the brains to develop a technology that we hope can change the world.”
Anders adds that Stockholm being such a green and clean capital means there is a heightened awareness about clean energy solutions.
“It’s in our blood, and that’s one part of why people who live in Stockholm, without really thinking about it, are very self-aware of how we think about sustainability and how we use energy,” he says.
And that may be part of what led CorPower Ocean founder Stig Lundbäck – a doctor who spent most of his career studying pumping principles of the human heart – to come up with a technical innovation for wave power inspired by the organ that keeps blood pumping through the human body.
“He saw that there is a pre-tension system in the heart that draws back the blood to the heart automatically, and he realised that such a system could help a power plant survive in a harsh ocean environment,” CorPower Ocean Commercial Director Anders Jansson explains.
This realisation is the origin of the company’s WaveSpring technology.
“This technology enabled us to solve the two main challenges within wave energy,” says Anders – building a system of the right size and being able to make power from different sized waves.
Previously, companies have either build systems that were too “small and fragile” to survive major storms; or they built systems that were too large and weren’t commercially viable.
“With WaveSpring's pre-tension system, like in the human heart, we can control all types of wave conditions,” Anders explains. “So we can produce power from quite small waves, and still survive really large, severe waves.”
The significance of this technology, Anders tells us, is enormous – even in a global context.
“There is no one else in the world that can do that in an effective way – we can produce significantly more electricity with much less material, meaning we can produce wave power at a low cost.”
As a result, Corpower Ocean believe they have the chance to make wave power commercially viable…and that’s no small attainment, particularly when you look at the figures.
“Wave power can actually generate 10-20 percent of global electricity consumption – that is a substantial amount of electricity that, today, is not utilised at all,” Anders explains.
Hot water, cool energy solutions
Speaking of remarkably effective energy solutions, Stockholm is also home to Climeon – which is based on a simple idea, according to CEO and co-founder Thomas Öström: turning hot water into electricity.
More than 50 percent of energy used today is wasted after it’s used, dumped as what Thomas calls “low energy waste heat”. It’s a problem in all kinds of industries, from manufacturing to chemical refineries.
Harnessing this energy is not a new idea – but no one has really been able to pull it off.
“The challenge is to find a solution with low energy loss but that is also cost-effective,” Thomas explains.
And while it took them a few years, the team at Climeon managed to pull it off.
“We’ve found a way where the energy loss throughout the conversion is almost zero,” he says. “It’s not really one invention in the machine; it’s five.”
Basically, the Climeon system uses the temperature difference between hot and cold water to create a pressure difference. The pressure difference drives a turbine and the turbine drives a generator – and out comes electricity.
“The whole system works in a vacuum, which has a number of benefits. The pressure is so low in the system that we need very little material and we waste very little energy. It’s extremely efficient.”
Another key to the efficiency of the project is its size and format.
“The whole thing has been built like Lego blocks,” Thomas explains. “Each 150-kilowatt module – enough to power 100 houses – is just 2 by 2 metres in size. And when you build up a power plant you can use them just like Legos and take how many modules you need. It’s efficient and low-cost.”
He adds that many innovations born in the Swedish capital aren’t just thanks to its passion for sustainability, but also the stability of the country itself.
“We have a safety net here. There’s a system to help you out if you fail, which allows you to take a chance and start a company like this,” he says. “It creates an environment that is healthy for taking chances.”
And in addition, there’s something about Stockholm that’s simply…special.
“You have the culture and climate here, all the big companies, plenty of investors – and perhaps most importantly, talent,” Thomas states. “Stockholm is the innovation hub of Sweden.”