About the Renovation of Kihnu School

The school building on the island of Kihnu, built in 1972, is in desperate need of renovation. The Islands Energy Agency will help the school to create the most efficient energy solution possible, using a one stop shop approach. Kihnu Municipality has authorised the Islands Energy Agency to manage the whole renovation process and to conduct a design-build procurement in order to achieve the lowest cost of operation and energy efficient solution instead of the cheapest price. The renovation will take place in the summer of 2025 and will be supported by the State Shared Service Centre.

In 2023, an energy audit was carried out on the building, which revealed uneven insulation and the presence of cold bridges at the joints between walls and ceilings. Ground heating is not able to heat the school building sufficiently in cold weather, so hot water is produced using electricity. Due to these problems, the temperature in the building fluctuates and the building currently has an energy class of F.

Under the procurement, the building will be insulated and will receive new heating and ventilation systems. As a result of the works, the building’s energy consumption and carbon footprint will be reduced and the school building will receive an energy class A label.

Summary of audit findings and savings proposals

The average total consumption of heating energy (geothermal heat pump electricity) for the period 2021-2022 was measured and calculated at 50 MWh/year. The average heating energy consumption over the last two full years, standardized to the base year, is 62 MWh/year and, based on the building’s heated surface area of 861.2 m², the average specific heating energy consumption per unit surface area over the base year is 72 kWh/m². The energy performance value of the building in its existing situation given standard use puts it in F class: 300 kWh/(m² *year) (kWh per square metre of heated area). As a result of the audit, a solution has been proposed for the renovation of the building, which can technically reduce the heating energy costs and improve the indoor climate quality.

Necessary work:

• Additional insulation of the loft and sloping roof sections and all external walls.
• Insulating the floors.
• Replacement of windows with new 3x glazing units.
• Installation of new external doors.
• Installation of a hot water system based on geothermal heat pump.
• Installation of heat recovery ventilation systems.
• Configuring the heating system according to the heat demand of the building.
• Installing cooling systems to prevent summer overheating.
• Replacing old gas-discharge luminaires with LED luminaires.
• Installing solar panels.

Calculations of changes in energy supplied to the building, operating costs, and the CO² emission factor of consumed energy.

The total energy consumption of the school building will decrease by 58,411 kWh per year compared to the pre-renovation state of the building.

The change in the maintenance costs of the school building in the future compared to the current consumption expenses is a decrease of €1038 per year.