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Carbon / Low-carbon

A low-carbon infrastructure by design

Our mission is to deploy computing power in existing buildings rather than in data centers, which makes it possible to recover the IT waste heat.
Paul Benoit, President & co-founder

The digital circular economy

Turning waste into a resource

A computer that computes is a computer that produces heat: In a traditional data center, this heat is both lost and cooled.
• By decentralizing the computing power, Qarnot valorizes the heat released by the servers directly where it is needed, in buildings
• By limiting the transport of heat to its strict minimum, Qarnot manages to recover 96% of it
• By sharing the uses, Qarnot allows to reduce two carbon footprints: the one of the computing and the one of the heating

Carbon facts

Tool to manage your energy consumption

Qarnot provides you with a detailed report of each item of expenditure and energy saving for each of your tasks.

This report allows you:

• to easily obtain the necessary information if you have to carry out an assessment (GHG, Carbon Assessment, CNC or European subsidies, etc.)
• to rely on reliable data if you index your managers' remuneration to the reduction of their carbon footprint
• to monitor the energy consumption of your tasks in real time
• to benefit from a lever to act effectively on the reduction of their environmental impact

Understanding the indicators

PUE, ERE, ERF… what do they measure?

PUE (Power Usage Effectiveness): is obtained by dividing the total energy consumed by the data center by the total energy used by the IT equipment (server, storage, network) over one year. The ideal is to aim for 1.

ERE (Energy Reuse Effectiveness): it is the amount of energy consumed by the data center minus the energy reused, divided by the energy consumed by the IT. If the data center is not equipped to recover energy from its equipment, the ERE is equal to the PUE. Otherwise, it is lower. Ideally, it should be close to 0.

The ERF is the ratio of reused energy and the total energy consumed by the data center.

Concrete cases!

Let's consider for this example facilities located in France (electricity mix: 60gCO2eq/kWh), and whose IT heat reuse replaces a gas heat source (227gCO2eq/kWh).

  • Data center A has a PUE of 1.20, so it is considered efficient. However, it does not reuse the heat released by the IT equipment.
  • Data Center B has a PUE of 1.50 but recycles 50% of the heat produced by its IT, for example to heat a building, which is 33% of its total electricity consumption. This allows it to save 51% of CO2 compared to data center A despite a higher total consumption (PUE B > PUE A).
  • The QB-1s generate both a very low PUE, and above all, 96% of the IT heat is used to heat water. The Qarnot solution allows a 79% CO2 saving compared to data center A and 68% compared to data center B.