TechHQ visited two of Iceland’s data centers to find out how their expansions were impacting the country’s delicate environment. Published 1 December 2023
Part 3: Data centers
It would be easy for Iceland to overlook the true environmental impact of data centers, as they make up 5.3 percent of the country’s GDP. Powered by 100 percent renewable energy, the facilities already have a good reputation. When TechHQ visited Iceland in October, we explored two of the country’s data centers, run by atNorth and Borealis, to find out how their respective expansions were impacting the environment.
atNorth has three sites in Iceland but seven overall, with the others located in Finland, Sweden, and Denmark. It has ambitions to be the largest data center operator in the Nordics and boasts one of the lowest TCOs for co-location in the world. In total, atNorth has 126 MW of capacity and offers co-location service and ‘HPC as a service’. “If a customer is not willing to invest heavily into a big stack of HPC clusters, he can tap into us,” said Jóhann Þór Jónsson, the Director of Site Selection for atNorth. “If he wants to come and do rendering for 24 hours or 12 hours, he can come and tap into it and go back again.” Jónsson added that this is useful for the film and engineering industries, but atNorth also wants to attract hyperscaler customers like AWS and Google Cloud.
ICE03, a pristine white facility set between mountains in Akureyri, opened in the summer of 2023. Its current power capacity is 12 MW, but this will likely expand as the density of its racks increases. It boasts a power usage effectiveness (PUE) of less than 1.2 and is powered primarily by geothermal energy. It also takes some energy from the Kárahnjúkar Hydropower Plant in the east.
The environmental impact – cool or uncool?
Natural cooling means that Icelandic data centers use between 24 and 31 percent less energy than equivalent sites in the UK or USA, according to atNorth. However, both data center providers try to go beyond just leveraging Iceland’s ecological advantages to be environmentally friendly. István Végh-Sigurvinsson is the Sustainability Officer at Borealis and, at the Datacenter Forum, said it is his responsibility to choose vendors for hardware, cooling, and other electrical infrastructure “that are on the sustainability journey, at least” to maintain the company’s environmental standards.
The frame of atNorth’s ICE03 is built from ‘glulam’ timber instead of steel, as it is better for the environment, more fire resistant, and better absorbs seismic activity. The panels are made of steel but insulated with Icelandic rock wool, which is also fire-resistant. Having strong materials to protect the facilities is important on an island situated directly on the mid-Atlantic ridge with 33 active volcanic systems.
Data centers famously produce a lot of heat, and one of the most attractive elements of Iceland for hosting these facilities is the cold climate which allows for cheap and efficient cooling. Currently, both atNorth and Borealis implement direct air cooling (DAC), where cold outdoor air is allowed to flow indoors to bring down the temperature of units. Large doors around the outside of the pressurized rooms at atNorth allow the air to come in for the units to suck up. The units then blow warm air back into the room’s central area, which rises and flows out grates above the doors. There are cold air intakes on both sides of the facility which can be opened depending on which way the winds are blowing.
Direct liquid cooling of data centers with water in a cold climate like Iceland can be more environmentally friendly than direct air cooling. Water has a higher heat capacity than air, enabling more efficient heat transfer to the surrounding environment or dedicated cooling systems. Closed-loop cooling is also better than evaporative cooling, which removes gallons of water – a precious resource, despite its abundance – from the watershed.
However, direct liquid cooling with water requires the addition of a chemical coolant to stop it from freezing, and that could harm the environment if it leaked or was disposed of improperly. Furthermore, water cooling requires more sophisticated infrastructure and maintenance than air cooling, which can result in higher energy use. Direct air cooling doesn’t involve coolant, but it is less efficient. Therefore, it may require more power to maintain optimal temperatures inside the data center.
Heat of the moment
As well as electricity, the geothermal power plants Hellisheiði and Nesjavellir provide more than half of the hot water used for district heating in the Reykjavík area. Drillings into geothermal fields in and around the capital are the other primary sources of hot water, which is also used for swimming pools, snow melting, and, importantly, greenhouse cultivation. Iceland’s climate prevents the growth of many vegetables, so greenhouses reduce the need to import food.
But the geothermal reservoirs are not the only thing producing significant amounts of heat in Iceland; the data centers do, too. Some of them, like atNorth, sell their excess heat to energy companies that then distribute it to residents through the district heating plant. “There’s a long-standing know-how in Iceland on how to distribute heat over a long distance,” said Mr Jónsson.
Read the complete article online here. Read part 1 and part 2