Oulu University Hospital 

The output of Oulu University Hospital’s backup power system quadrupled 

Backup power units at Oulu University Hospital secure a growing number of systems after an expansion. The backup power solution built by kW-set will keep the hospital in operation even during a longer power outage.

Oulu University Hospital is expanding one new building at a time. Alliance A and B of the OYS 2030 project were completed in summer 2023, and the hospital received a much more comprehensive backup power system. Demand for backup power has evolved alongside medicine. 

“Backup power was earlier used only to secure life-support and security systems, but now backup power also supplies electricity to telecommunications networks, security systems and data connections, including the hospital’s internal mobile network,” says Mika Joona, a specialist in electrical engineering in the wellbeing services county of North Ostrobothnia. 

“Many important building systems such as air conditioning, cooling and compressed air have also been secured with backup power,” says Sauli Kurttila, project manager in electrical engineering in the wellbeing services county. 

The hospital’s backup power output will increase fourfold from about 2 MW to 8 MW. According to Kurttila, the hospital will remain fully operational even during a longer power outage. 

“Previously, the aim was to finish any surgical operations in progress using backup power. Now, even a new operation can be started during a power outage, and imaging is also possible.” 

Backup power is connected to several building systems 

kW-set was responsible for the backup power delivery for Alliance A and B as part of Caverion Finland Oy’s electricity contract. Caverion’s Project Manager Tapio Hannus has already worked with kW-set in similar deliveries for the central hospitals of Kainuu and Seinäjoki. 

“Our personal chemistries were a really good match this time as well. The backup power unit project for buildings A and B was larger than average and therefore also more demanding.” 

According to Kaarlo Valli, Sales Manager at kW-set, the technical requirements and interfaces with the hospital’s electrical and HVAC systems had been defined excellently in the backup power plan prepared by Granlund. Backup power units are connected to several different systems mechanically and physically through exhaust piping, electrical cabling and the ventilation system, to name a few. 

“It was easy for us to follow the procurement document and plan each detail such as the backup power control system and the layout of the backup power room.” 

Electricity supply is secured by redundant systems 

The new backup power system differs from the previous one not only in terms of power but also in that the new system is decentralised instead of the previous centralised one. According to Kurttila, the advantage is that the hospital will never go dark. Both new buildings have separate backup power units that can supply electricity to either building. 

“The diesel generators can be connected so that a single machine supplies electricity to both buildings.” 

The control systems in the main control centre for the backup power units are also redundant. “If one control centre malfunctions in a way that prevents operations, each backup power unit can be controlled with the other,” Valli says. Each of the four units has its own control centre, and in addition to daily tanks, large storage tanks. The large smart screens of the main control centre show the state of the entire system at a single glance. 

The backup power system is connected to the UPS system. It guarantees electricity supply for 15 seconds, during which the backup power units can start up. 

The backup power units were tested in thorough test runs 

All backup power units underwent thorough factory acceptance tests (FAT) in kW-set’s facilities in Tuusula under the watchful eyes of representatives of the wellbeing services county, Caverion and Granlund, which was in charge of designing the backup power system. 

“We carried out performance tests for the backup power generators and engines using an artificial load corresponding to the hospital’s actual load, i.e. load resistances,” Valli says. 

Specialists from the wellbeing services county have high confidence in the quality of the backup power units. “Our units are clearly among the best in the markets,” Joona says. The system was a success without any compromises, and the delivery went smoothly, including transport and installation, even though the units weigh 11,000–12,000 kg each. 

The silent operation of the backup power system came as a surprise 

In a hospital environment, backup power units are subject to requirements other than reliability. Focus was also on soundproofing, as the exhaust pipes of the backup power units are located on the roof in the deck parking area right next to the main entrance. 

“While we were a little troubled beforehand about the harm caused to the local environment, there was no need for such worry,” Kurttila says satisfied. The sound levels are lower than the regular 75 decibels: 60 dB. “I was very positively surprised by how quiet the units are.” 

The backup power unit supplier is responsible for maintenance and lifecycle services 

The backup power solution was designed for a long lifecycle of 30–40 years because the retrofitting of backup power units is expensive. It was important for Oulu Central Hospital that the backup power supplier also provides maintenance services and rapid assistance in exceptional situations. 

“kW-set provides us with a maintenance organisation close to us, and other lifecycle services ensure the availability of spare parts during operations,” Joona says. kW-set is also responsible for the scheduled maintenance of the backup power units. 

The various parties to the alliance are satisfied with the content, installation, commissioning and training of the backup power solution, all of which were carried out on time. “I would recommend kW-set for its reliability and system-wide expertise,” Hannus says. 

Kurttila also states that kW-set is among the best backup power specialists in Finland. Trust has only strengthened during the project. “There have been no problems. Operating tests and acceptance inspections were carried out thoroughly, and everything that was agreed has also been done.” 

Next, cooperation between the wellbeing services county of Lapland and kW-set will continue in Alliance C: the backup power contract for building F. It corresponds in size to Alliance A and B.