The internet has become so commonplace that many of us have difficulty imagining what it takes to make this digital world a reality, including the number of servers and hubs required to power it. Most data centers worldwide are heavily relying on fossil fuels to produce electricity and cooling required to run up all those equipments. This is what some call the dark side of the internet. Statistics are eloquent in that respect: a single Google search consumes 20 mg of CO2, while an email is between 0,3 to 4 g. Therefore, the 192 billion emails we send annually are equivalent to the footprint of 3,1 million cars per year, while Youtube streaming alone amounts for 1,2% of the world’s electricity consumption. Estimates show that the internet consumes around 1037 TWh of electricity globally, representing the production of dozens of nuclear power stations across the world. This is finally representing 609 million tonnes of greenhouse gas emissions, equivalent to the emissions from all civilian flights over a year!
Given these statistics, data centers have often been criticised as they represent roughly 25% of internet’s world emissions. Acknowledging this situation is hard and takes time; however, today most internet stakeholders are trying to find ways to make it greener.
In this respect, bioenergy has a lot to offer, whether providing electricity or heating and cooling solutions. A good example showing some great synergies can be found in Luxembourg, close to the city of Bissen, where Kiowatt plant operates.
Kiowatt uses waste wood to produce electricity, heating and cooling. The project began in 2011, when LuxEnergie S.A. a Luxembourgish energy contracting company, and the Groupe François, a Belgian wood industry and bioenergy company, decided to create a joint venture to take advantage of all bioenergy benefits on a shared site.
Inside Kiowatt plant everything starts with a 17 MWboiler designed to use local wood waste which was not utilised before. This boiler is equipped with a superheater appliance, providing 420°C steam which powers a turbine to produce both heat and power. The electricity produced, around 21 GWh is then sold directly on the grid to provide green energy in the region. The heat, representing the most important energy production (93 GWh) is used for three key applications:
- The first part of the remaining heat is used to dry low quality fresh wood for the manufacturing of wood pellets. Those pellets are mostly sold afterwards under the BADGER Pellets brand, providing stove and boiler owners in the region with sustainable and reliable renewable fuel.
- Another part of the remaining heat is used to produce cold with two absorption machines that convert the heat into cooling with an efficiency close to 70%. The cooling system is then routed to the data center closed by operated by DataCenterEnergie Company S.A. to provide internet servers with a renewable source of cooling. In 2013, this synergy was the first of its kind in Europe.
- A final part is sent to a local district heating net, providing green heat to the industrial area surrounding the plant and to the village of Bissen.
Today, Kiowatt provides 15 full time jobs onsite and contributes quite significantly to the Luxembourg renewable energy targets. The only Kiowatt plant represents 5% of Luxembourg’s goals for the production of green electricity, heating and cooling by 2020. According to experts’ estimations, some 350.000 tonnes of CO2 will not be emitted on the period thanks to the project, contributing to a direct reduction of 14.2% of GHG emissions targets for the country!
More detailed information could be found on Kiowatt website: http://www.kiowatt.lu/en
You can also watch Kiowatt plant’s presentation on Youtube: https://www.youtube.com/watch?v=p2CVV-x3Srw
Author: Jean-Baptiste Boucher