Lettuce and servers - industrial symbiosis through waste heat from the data center

RISE has presented the work with industrial symbiosis in Boden in an appendix to the magazine Dagens Industri.

Industrial symbiosis means that two different industries achieve economic and environmental benefits by organizing themselves around the exchange of resources, such as material flows or energy. In northern Sweden, such a match has arisen between two unlikely parties. RISE Research Institutes of Sweden has in partnership with others begun an interesting development of this in Boden.

Since 2016, the government has had a strategy aimed at increasing self-sufficiency and reducing emissions in connection with food imports. The starting point is tough, today 91% of all vegetables consumed in northern Sweden are imported. But growing vegetables in Sweden can be challenging, especially in the north as a greenhouse cultivation requires heating all year round, ie even in summer. Energy consumption in Swedish greenhouses was 627 GWh in 2011 and 41% came from oil and natural gas. What if instead there was an industry that generated a surplus of low-temperature waste heat?

Datacenter is an energy-intensive industry that accounts for 1-2% of the world's total demand for electricity. The electricity used to power a center's IT equipment is usually discharged into the environment as air with a temperature of about 30–45 ° C. At the ICE data center at RISE, an idea was raised to try to reuse the excess heat generated in the company's server halls.

In 2019, an attempt was initiated to dry the renewable biofuel biomass using the waste heat from the Boden Type One Data Center (BTDC). The results showed that up to 40% of the excess heat from BTDC could be recovered and used in the drying process.

The next step was to investigate the possibilities of growing mealworms in the waste heat. In addition to being a good alternative protein source for meat, fish and poultry, mealworms also have a relevant area of ​​use as chicken feed. This is important as chicken farming has steadily declined in Norrbotten since the 1990s and in 2014 self-sufficiency reached 0%. Through the project, a circular supply system began to emerge where mealworms grown in data centers become feed for chickens and the chickens' droppings become manure in greenhouses, which in turn are heated by the same waste heat that enables mealworm cultivation.

The largest potential benefit of the energy recovery investigated is found in vegetable farms. Analyzes show that up to 30% of the excess heat from a data center can be recovered every year. The company Containing Greens has a business idea that takes advantage of this and has established itself in one of the ICE data centers where those from vertical hydroponic crops harvest lettuce that is delivered to local restaurants.

Today, there are several hundred megawatts of data centers installed in Sweden. In northern Sweden's cool climate, a megawatt data center effect can heat a greenhouse area, which corresponds to an increase in self-sufficiency by 8%. High heating costs of greenhouses can be largely reduced with excess heat as an alternative energy source and calculations even show a potentially lower total production cost than traditional crops. IUS, an industrial symbiosis park in Boden, is the place where the partnership between greenhouses and data centers will be realized and scaled up. Here, several other types of activities, such as fish and insect farms and hydropower plants, will share resource streams of by-products and / or surpluses and together create something completely unique.