Dovile Baltrukeniene

Green Energy from Used Coffee Grounds

Can coffee drinking be made more sustainable? Last year, in Lithuania, we had a great idea how to increase the lifespan of a coffee bean and to get something magical out of it.

In this fast-paced world where consumer culture dominates our everyday lives, many of us should stop and consider more sustainable lifestyle. Human activity is the main cause of climate change, and we here at Paulig work very hard to ensure a sustainable and environmentally friendly business. After all, if we will not do anything, 50 years from now there might not be any coffee left – and that is just not the kind of world we want to live in. 

So, what can we do if we want to increase the lifespan of a coffee bean? Well, last year we had a magical idea: we recycled used coffee grounds and used them to illuminate the main Christmas tree in the city of Kaunas, Lithuania.

Used coffee grounds Christmas tree

A very bright idea: Powering lights with old coffee grounds

When we had the idea of recycling coffee grounds, we needed to figure out a way to spread it to others. Our main goal was not only to generate green energy for powering Christmas lights but also to include as many people as possible in this project. 

If we wanted to attract people's attention, we needed to focus on the result. Therefore, we decided to get people hyped on using this unusual way of powering lights. We chose Kaunas because it is the second largest city in Lithuania and currently in a stage of rapid modern development.

In order to acquire enough coffee grounds, we wanted everyone to join – not just our clients. We invited cafés, hotels, restaurants, offices and gas stations to join us in this project.

The result: 15K of coffee grounds and 8000 kWh of clean energy

In the end, more than 170 businesses joined our project. Half of them actually reached out to us themselves because they wanted to be a part of the project. We gathered coffee grounds from these companies all through November. And when December came, all the residents of Kaunas city were invited to join: a recycling container was put in the City Hall square, specifically for disposing of used coffee grounds, so everyone who wanted to help keep the Christmas tree illuminated was able to join. 

In two months, we gathered more than 15 tons of coffee grounds that were used to produce around 8000 kWh of clean energy. Only 5 or 6 tons of coffee grounds were necessary to keep the Christmas tree lights going, so with all the hard work that was put in the project, we tripled the amount needed!

The writer, Dovile Baltrukeniene, is Marketing and products coordinator in Paulig Lithuania.

Recycling spent coffee grounds: How does it work?

This entire project showed that in order to create a sustainable environment, it is necessary to start from ourselves and there will always be partners who want to join and help in this path. We asked a recycling company, Modus energy from Lithuania, to tell us how the bio-based recycling actually works.

Have you ever dreamed of a world where you could take the used coffee grounds and charge your phone with electricity made out from those coffee grounds? Well, we're not quite in "Back to the Future" yet, but in this bioenergy approach, you'll discover that coffee grounds, biodegradable cups and other decaying organic matter, called biomass, are a rich source of energy.

We love drinking coffee, and we do it on our daily basis. We worry about recycling the coffee cups, but we easily forget what happens before the ready-to-drink coffee is in our hands. 

Actually, every time someone prepares a cup of coffee, a fraction of organic waste is generated. That fraction of organics is in a form of spent coffee grounds. On top of that, electricity is being consumed for the coffee preparation process. We know how to connect these things. To be precise, we know how to produce the electricity from the collected spent coffee grounds. 

As mentioned before, a major fraction of coffee grounds is organic and, if left for a longer time, it degrades and produces CO2 and it smells bad. However, if the same coffee grounds were put into warm temperature and no oxygen presence (anaerobic conditions) bacteria will enjoy eating the coffee grounds and producing biogas. Yes, we are talking methane here - biomethane! In a biogas plant, this process takes place in an anaerobic digester and is accelerated by creating the best possible conditions for micro-organisms and bacteria to multiply, which leads to a highly efficient breakdown of materials.

Next, we collect these volumes of biogas, clean it and burn in our engines for the sake of sustainable electricity and heat production.

Every ton of spent coffee grounds delivered to our biogas plants is being converted to 500 kWh of electricity and 500 kWh of heat. You can do a lot with this amount of electricity: take a BMW i3 and drive 2900 km with it!

And that's not the end. The degraded coffee grounds are delivered back to the fields as an organic fertilizer. They contain a significant number of elements which are beneficial for the plants to grow. Have you ever heard about the circular sustainable economy approach? Fellows, this is the perfect example of it: while applying this concept, you are shifting your coffee drinking routine to a new sustainable level!

Recycling coffee