Generating Electricity From Living Plants

Posted in:

3

Can you imagine looking at wetlands and green fields when driving out of the city, only to realise electricity is being produced there? Or instead of installing solar panels on your house’s roof, build a rooftop garden which could end up powering your whole home?

These are the kinds of questions an innovative company is asking.

Dutch start-up company, Plant-e, has found a way to get electricity from plants, and have been using them to power Wi-Fi, cell phone chargers, streetlights, and even their own headquarters in the Netherlands.

About Plant-e

Plant-e was founded back in 2009 as a different division from the sub-department of Environmental Technology of Wageningen University in the Netherlands. Marjolein Helder, PhD., is the CEO of the company, while assistant professor David Strik works closely with her.

Their aim: to provide renewable energy to the 1.4 billion people around the world who have no access to electricity or clean power.

To do this, they are harvesting energy from living plants in wet areas, such as rice paddy fields, without damaging the plants themselves.

The company has operated so far on the revenue from subsidies and awards, rather than investors. Even though they are trying to find the right investors, for the moment they have been focusing on getting the right technology and projects going.

In November 2014, Plant-e developed a successful and bold project called “Starry Sky”, where they were able to light up more than 300 LED streetlights in two different sites near Amsterdam.

How does the technology work?

All it takes for Plant-e to get this new clean source of power is a field of plants, light, carbon dioxide and water.

Plants create their food using photosynthesis. When this happens, a large portion of the organic matter generated is excreted by the roots back to the soil. That organic matter is then consumed by microorganisms that live in the soil, releasing electrons as a result of this consumption.

By placing an electrode near the roots, Plant-e has been able to gather this energy waster, turning it into electricity.

The company was always concerned about the wellbeing of the plants in this whole process, however they remain unharmed, and tests show that their growth is not at all affected by the presence of electrodes, which provide a source of power during day and night.

The ideal location for this process to happen is wetlands or watery fields, such as rice paddies. And the best thing about this process is it doesn’t matter if the water is polluted, so areas that are currently unsuitable or have been discarded for growing crops could have a new use as power sources.

In addition, the technology doesn’t require any complex infrastructure. All they need is some lamps powered by salt water, making it easy to set up in remote regions that have no power.

Current products and future challenges

Plant-e demonstrated in 2009 that plant microbial fuel cells, with the help of micro-organisms, could generate and convert electrical energy from chemical energy.

The first project was operating as a modular system consisting of 100 square-metre installations. Each of these has 400 individual modules, fitted with the proper technology and plants. This system was tested and used to power outdoor lighting, as well as small and medium applications such as Wi-Fi and phone chargers.

It was a big achievement for the project when in 2014, 50 x 50cm plant trays (generating 5 Volts each) were the first commercial systems launched.

Next, larger scale modular systems are set to create power for whole buildings by implementing the same method using green roofs. Sourcing electricity using this method is sustainable, provides insulation, water storage and an improved biodiversity.
Plant-e is already developing a tubular system, with the ambition of generating larger amounts of electricity from wet areas. Their dream for the next 20-30 years is to generate clean electricity around the world from suitable wetlands or wet areas.

The main challenge for the company is the limits of how far they can scale up this modular system and the quantity of energy they can generate from it to have a completely reliable, commercial product.

Plant-e can’t compete with other energy sources yet. However, with further research the challenge to meet large scale efficiency is definitely looking promising.

Cost effectiveness

Even though they can’t yet compete on price with the famous and highly effective wind and solar power sources, the company is confident they will reach the point of competition.

Currently, the company has managed to generate one watt of electricity per square-metre, with the possibility of reaching three watts. By their calculations, if they can produce three watts per square-metre, they could power and average family home in the Netherlands with only 125 square-metres of land.

Home and DIY products

In addition to their busy schedule and all the amazing projects they are currently developing to get clean energy in parts of the world where there’s a lack of it, Plant-e has also plans to release a square-foot mini garden that could grow herbs and vegetables while gathering energy at the same time, to power small electronics at home.

And a DIY Plant-e box kit is also in the work, with the aim to aid workshops or practical classes in schools.