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19 December 2019

Stockholm blog: Ending GrowSmarter and heating Stockholm with internet traffic

In the final days of GrowSmarter our team in Stockholm have been busy telling the world about all the solutions we implemented over the past five years. It has been a great experience with some major highlights. First, in Barcelona at the Smart City Expo World Congress, Stockholm won the World Smart City Award for our leadership of GrowSmarter. That kind of recognition for our efforts of course meant a lot to all of us involved with GrowSmarter.

Less than two weeks later we were also happy to welcome guests from all over Europe to Stockholm for the final conference of GrowSmarter. It involved speeches by our Mayor, Anna König Jerlmyr, Barcelona’s Commissioner for the 2030 Agenda Miquel Rodriguez Planas, Mayor of Cologne Dr. Ralf Heinen and Mr. Svetoslav Mihaylov from the European Commission. A lot of our industrial partners and the leaders of different technical solutions also had the chance to present the great work they have done.

On top of all the people coming to Stockholm for our final conference, I also had the pleasure of welcoming a news crew from Euronews visiting to Stockholm to do a story on the solutions we have implemented in GrowSmarter and the project as a whole. I spoke to them about why and how Stockholm worked with smart city solutions (read my previous blog detailing our many different smart city solutions and what future plans we have with them in Stockholm). The segment will be a longer one and will start airing on Euronews in January 2020.

Will the internet heat Stockholm in the future?

One of the solutions I showed to the visiting reports was the data centre, where a GrowSmarter solution implemented by Stockholm’s Exergi recovers heat and supplies it into the District Heating system.

According to Cisco the annual global internet traffic will increase threefold over the next five years and reach 4,8 zettabytes in 2022. The increase in internet traffic also means that more and more data centers must be built. Sweden is already very attractive for data center investments for several reasons. Sweden is a safe country, it has hydro power, extened optical fiber network and also a low energy tax, especially for data centers. Facebook built a datacenter in Luleå and is currently expanding it. Amazon has three datacenters near Stockholm nearing completion, Google has recently acquired 109 hectares of land in Avesta and Microsoft has acquired 130 hectares of land in Gävle for building datacenters.

The increase in global ip traffic will also increase the demand for electricity. According to the GrowSmarter partner KTH the global internet traffic is currently using 10% of the total electricity in the world so approximately 2 500 TWh per year. By comparison the total renewable electricity production was 2 100 TWh per year in 2017. Facebook has announced that it will purchase 100 percent renewable energy and reduce their greenhouse gas emissions by 75 percent by 2020 for their datacenters. So more and more of the renewable energy would be consumed by datacenters.

There is one very important isse that is often overlooked when these investments are mentioned: datacenters must be cooled down and in that process a lot of waste heat is produced. The size of a datacenter is defined in MW and in Sweden a datacenter of 1 MW will produce enough waste heat to heat up 1000 apartments if we can recover that heat. This can be done in cities with district heating like in Stockholm. But if you build the datacenter far outside the city, then all this waste heat is lost. Unfortunately this has happened with datacenter investments in Sweden. In Skellefteå a new data park is launched which will have a capacity of up to 120 MW and will run solely on renewable energy. It will be located on land owned by Skellefteå Kraft, next to a hydro power plant in Finnfors, Skellefteå. This village has less than 200 inhabitants, while the waste heat could heat up 120 000 apartments. The case is similar in the other large data center investments mentioned above.

Stockholm will need to build 140 000 new apartments until 2030, so how could these be heated up with waste heat from datacenters? Stockholm Exergi launched a service called ’Open district heating’ to recover excess heat from datacenters. Open District Heating enables customer to gain revenue on its excess heat that otherwise have been wasted and it was launched to market 2014. Today it has 30 customers and during 2018 a total amount of 113 GWh heat was recovered, corresponding heating of 31 000 apartments p.a. In the GrowSmarter project heat is recovered from GleSYS’s data center in Västberga in the southern part of Stockholm. Two heat pumps were installed in June -17. The heat pumps (Carrier 61XWH-ZE0501) are the first of its kind in Sweden with a heat output temperature of 85 °C and with refrigerant HFO R1234ze that reduces the environmental impact compared to traditional refrigerants.

Joakim Jarstorp, Head of the Data Center of GleSys. He is being interviewed by Cyril Fourneris from EuroNewsJoakim Jarstorp, Head of the Data Center of GleSys. He is being interviewed by Cyril Fourneris from EuroNews

We have now evaluated this installation both technically and economically. For Stockholm Exergi the recovered heat has been cost efficient compared to other ways of producing heat. With a large-scale implementation of heat recovery into the district heating network, Stockholm Exergi gains other values such as avoided peak production capacity investments and reduced operation and maintenance costs thanks to third party ownership of the production asset. For the data center, Glesys, heat recovery generates a revenue stream from the waste heat that otherwise would cost money to get rid of.

Glesys had expansion plans for the data center and an investment need for more cooling capacity. Instead of another conventional cooling machine the growSmarter heat pump solution with heat recovery was chosen. Comparing with the traditional option this measure shows economical gains for the supplier with a pay-back period for the supplier of about 5 years’ time. The economical values will sustain over the total technical lifetime of approximately 15-25 years.

If we do want to heat up the new apartments with waste heat from datacenters, Stockholm needs to attract investments into the city. Stockholm Data Parks is an initiative by the City of Stockholm, district heating and cooling provider Stockholm Exergi, power grid operator Ellevio and dark fiber provider Stokab. The vision is a data center industry where no heat is wasted. The City’s objective is to be entirely fossil fuel free by 2040, and invite data centers to play a key role in this transition. IP-Only Enterprise is one of the companies now investing in Stockholm Data Park. The data center size will be approximately 24 MW and this can heat up 24 000 apartments in 2022.

So to answer my original question. Yes, the internet could heat up most of the 140 000 new apartments expected to be built in Stockholm by 2030. All we need for that to happen is datacentes investments in Stockholm where the waste heat can be recovered.

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