SPARK HUB is an inspiring startup and technology hub in the city center of Tartu. It houses more than 200 entrepreneurial people and thanks to its shared spaces like open kitchens and lounges, provides an ideal environment for networking and exchange of ideas. In addition to different technology and entrepreneurship oriented companies and organizations, SPARK HUB also has meeting rooms, event spaces and a cafeteria.

The four-story building consists of two parts which were completed at different times – the older part in 1998 and the newer one in 2003. Total area of the building is 4871 m2 and the two ventilation units under discussion in this article provide air for 2500-3000 m2 of the total space.

In early 2020, the real estate management team of SPARK HUB was looking for options for reducing their energy bills. Since they had worked with Calidity before to improve the indoor climate of their other building sTARTUp HUB, they reached out for consultation. Calidity reviewed the ventilation schedules used in SPARK HUB and found that the schedules of two units running on the 3rd and the 4th floor might not be very optimal.

One of the two units is servicing the 3th floor and part of the 4th floor and the other one providing airflow to the other zone of the 4th floor. On the previous schedule, the ventilation unit servicing both floors was set to work at 70% of its maximum speed from 8 AM  to 8 PM and to be turned off for the rest of the day on the 3rd floor. On the 4th floor, it was configured to be turned on at 40% at 7 AM and to increase its operation to 70% from 9 AM until 6:30 PM when it switched back to 40% at the end of the working day. Ventilation was turned completely off at midnight. On weekends, it ran on a different schedule — ventilation worked at 40% from 9 AM to 10:30 PM. The other unit catering only for part of the 4th floor was started at 7 AM at 70%, switched to 40% at 10 PM and turned off at midnight. On weekends, it ran at 40% from 7 AM to 10 PM.

To improve energy efficiency, indoor climate monitoring devices were installed to both ventilation units to regulate the ventilation rate based on the CO2 level in different parts of the building.

Two sensors were installed on the 3rd floor and six on the 4th floor. The ventilation units were configured to constantly work at a low rate and increase their speed only when CO2 rises. The ventilation unit servicing both floors was set to work at 15% on the 3rd floor and at 30% on the 4th floor and the other unit taking care of the air supply of the 4th floor was set to work at 25%. This allows to save energy while not compromising on residents’ health and comfort.

Thanks to the new schedules and implemented automation, SPARK HUB obtained remarkable savings in energy consumed by the 3rd and the 4th floor ventilation units. They now use 76% less energy than before on average, while keeping the indoor climate healthy for everyone.

If you are also interested in optimizing the energy consumption in your building and reducing your electricity bills, contact Calidity’s sales team. We’ll be happy to analyze the situation in your building and come up with an affordable solution that matches your needs and vision.