An intelligent hybrid system saves energy and improves production

| In 2018, Kiilto took a large step forwards in environmental issues when it started to utilize the waste heat generated by glue production at the Lempäälä plant. The globally unique hybrid system utilizes heat pump technology and geothermal heating and cooling.

The Finnish company Kiilto Oy manufactures chemicals for construction and industrial purposes at its Lempäälä plant. The polymerization process is one of the stages of manufacturing adhesives which releases a lot of thermal energy. During the process, the reactor must be cooled mechanically. For cooling, industrial heat pumps are used to recover waste heat for heating the plant and its water. More cooling power is drawn from the ground. The hybrid system, which replaces natural gas, utilizes geothermal heating and cooling in addition to the heat pump system in its heating and cooling processes. The bedrock acts as a heat storage excess waste heat for later reuse.

  • Heat is generated from the geothermal heating system to heat the property during the winter when the earth cools around the wells. Geocooling stored in geothermal wells is used during production to provide further cooling for the process. At the same time, the ground is warming up for the next nocturnal heating season, says Kiilto’s Technical Manager Vesa Juhannusvuori.
  • Improved cooling has significantly increased the production capacity of the polymerization process. An even bigger benefit is that production plans no longer need to be changed according to the cooling capacity, Juhannusvuori says.
  • Cooling water now remains at a constant temperature throughout the process, which increases the uniformity of production, says Juhannusvuori.

Kiilto heats hot water and 3.2 hectares of industrial properties with waste heat. With energy reuse Kiilto saves every year over 1800MWh of energy, which translates into an annual energy bill reduction of 88 000 euros. With the hybrid system, CO2 emissions have dropped over 350 000 kg per year.


EHPA invites everyone to submerge themselves in the possibilities that heat pumps are capable to offer in several industrial sectors. To read more stories the updated booklet is currently available on EHPA’s website.