Plant power: the new technology turning green roofs into living power plants

An innovative technology that uses living plants to generate energy has been launched in the Netherlands.

The technology harnesses the breakdown of organic matter produced by the plants in the soil and converts it into electricity that can be used to charge phones, power lights and cut down on a house’s reliance on external electricity sources.

Plant-e, the company behind the technology, has launched a range of products for different growing spaces, including parks, roofs and roundabouts. The first commercial installation of the product will be in Zaandam, the Netherlands, where the local government plans for the plants to provide on-the-go mobile charging for members of the public.


The technology, which was originally developed in 2009 at Wageningen University, works by converting waste electrons and protons generated by bacteria in the soil into useable electricity.

Speaking in a company video, Dr David Strik, Plant-e founder and assistant professor at Wageningen University, explains: “In our technology the electrons flow through a power harvester to the cathode, where oxygen, protons and electrons meet to produce water. So by easily placing two carbon electrodes in the soil we can produce living green electricity.”

The system can work all year round, with the only downtime being if the soil completely freezes in very cold weather – giving it a significant advantage over other renewable technologies that only work in certain weather conditions and areas of the world.


At present, Plant-e offers a number of products for specific spaces and functions. One, Plant-e Mobile, is a 100m² park with a mobile phone charging station.

Also available is Plant-e Hotspot, which uses the same area of park to provide wi-fi hotspots to visitors, something that could be extremely welcome in urban parks and gardens.

The company also offers Plant-e Roundabout, a version specifically provided for plant-covered roundabouts to power streetlights.

At the start of this month the company launched its Plant-e Green Electricity Roof system to businesses, and is planning to widen this to consumers soon. Suitable for any flat roof that can handle 200kg/m² of weight, the system has been trialled since 2010 on the roof of the Dutch Institute of Ecology.

The roof, which can be made from a wide variety of grasses, will require relatively low maintenance, requiring mowing just once a year. It should also be enough to put a serious dent in electricity bills – the company says 100m² will eventually be enough to cover the power needs of a typical Dutch household.

In the longer term the technology could also be used to large-scale living power plants in wetland areas such as “peat land, mangroves and rice paddies and delta areas”.

This would be using the Plant-e Tube System, a tubular system that the company is piloting from July. Plant-e hopes to have commercial versions of the system ready from 2015, so living power could soon be a major power source in many parts of the world.

Images and video courtesy of Plant-e.

Solar energy use in US sees mammoth growth over a year

The world’s largest solar thermal facility,  futuristic new buildings and phone charging points all led to a massive increase in the US’ solar industry last year. 

In total the usage of solar panels, when compared to the year before, increased 41% in the country during 2013. This accounts for the largest growth the industry has ever seen in the country, new findings by GTM Research show. 

Unsurprisingly, California is still leading the way in terms of areas that have the most solar power. More than half of the new solar set-up in the country during 2013 was installed in the Golden State.

Major projects across the state include Apple’s ‘spaceship HQ’, which will involve solar panels to help power the building and maintain its green status.


Solar was so big that it was the second-largest source of new electricity generating capacity in the US, and was only exceeded by natural gas.

Rhone Resch, SEIA president and CEO, said: “Today, solar is the fastest-growing source of renewable energy in America, generating enough clean, reliable and affordable electricity to power more than 2.2 million homes – and we’re just beginning to scratch the surface of our industry’s enormous potential.”

“Last year alone, solar created tens of thousands of new American jobs and pumped tens of billions of dollars into the US economy. In fact, more solar has been installed in the US in the last 18 months than in the 30 years prior. That’s a remarkable record of achievement.”

The US installed 4,751 MW of solar PV in 2013, which is nearly 15 times the amount installed just five years ago. This was helped by the falling cost of installation, which is now 15% lower than it was at the end of 2012.

flickr-mountain--ash- creativecommons

This year could also see a huge increase in the amount of solar energy being used in the US as California’s project BrightSource, which is believed to be the world’s largest solar thermal facility in the world, may become operational after tests last year confirmed it worked.

The solar park, located in the middle of Death Valley, will be able to power 140,000 homes and cost $2.2bn to create.

The solar uptake has not only been for major projects, as smaller initiatives have also been on the rise. Street Charge, which allows people to recharge their phones on the street, launched in New York last summer and is spreading further afield.

Shayle Kann, senior vice president at GTM research said the increase in solar panel usage showed the acceptance to use solar panels in the wider community.

“Perhaps more important than the numbers. 2013 offered the US solar market the first real glimpse of its path toward mainstream status.

“The combination of rapid customer adoption, grassroots support for solar, improved financing terms and public market successes displayed clear gains for solar in the eyes of both the general population and the investment community.”

Image 3 courtesy of Mountain/Ash under creative commons licence, via Flickr.