Renewable energy targets reached at Sakarinmäki school

The heating system based on renewable energy, used in Helen’s pilot project at the Sakarinmäki school complex, has met all expectations. In the first year of operation, geothermal heat accounted for 79 per cent and solar heat 3 per cent of the system.

New energy solutions are tested in the Sakarinmäki pilot project. A heating solution based on renewable energy – an entity of solar collectors, a geothermal system, an oil-fired boiler and heat stores – has been built at the school complex.

In the planning stage of the heating system, an 80% share of renewable energy was set as a target, to be reached with solar and geothermal heat. This target was met in the first year of operation in 2015: geothermal heat accounted for 79 per cent and solar heat 3 per cent.

In extremely cold weather, geothermal heat and the heat from solar collectors are not enough, and extra heating is needed. The heating system also includes an oil-fired heating plant, and combustion of bio oil has been successfully tested in its two oil boilers. This increased the share of renewable energy to about 90%.

– At the Sakarinmäki pilot site, we are monitoring how different production methods can be utilised locally in a single entity, says Unit Heat Juhani Aaltonen of Helen Ltd.  – In the current energy market, it is of utmost importance to regard a system, which consists of different production forms, as a single entity in order to make the system work efficiently in terms of the environment. This applies to both small and large heating entities.

The building of the Sakarinmäki school energy system is the first step in a more extensive trial taking place at Östersundom. In Sakarinmäki, heat production has also been introduced as part of education. The pupils have studied the principles of different heating methods in the physics classes and learned how to process and interpret statistical information based on the school’s energy data. They have also used this data when learning spreadsheet skills in the information technology classes. 

Open data: Heat production at the Sakarinmäki school and the share of different production methods can be monitored at and the monitoring data can also be downloaded for your own use.


• The Sakarinmäki school complex is located in Östersundom in East Helsinki

• The school’s old, light fuel oil-fired heating plant has been replaced with a new heating system that consists of geothermal heat, solar heat, a heating plant capable of utilising bio oil, and heat stores

• The new, distributed heating system was commissioned in October 2014

• The school complex serves 550 pupils and 126 nursery children every day

Published: 25.01.2016 13:27

Seija Uusitalo
Team manager, communications