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Nordkalk made its quarry pumps earn additional income with flexible energy management

29.09.2021

Eesti Energia's flexible energy management service enables Nordkalk to partially recoup the electricity costs of the Karinu quarry pumps.

Nordkalk is a leading provider of limestone-based products and solutions in Northern Europe with a significant presence in Central Europe. The lime factory in Rakke together with its limestone quarry in Karinu is one of the company's three production units in Estonia and the second one whose equipment, specifically pumps, are connected to a virtual power plant.


According to Raino Piirsalu, Quarry Master at Karinu, the flexible energy management solution has been in use for a few months and worked smoothly so far.

“The pumps take the groundwater infiltrating to the quarry to the sediment basins and from there to Lake Karinu. Although the water levels have been lower in summer, they mostly work around the clock, and since they use electricity, it means a constant cost for us,” Piirsalu explained. “However, the pumps can be switched off for a short period, for example 30 minutes, without substantially affecting the water levels. Flexible energy management allows us to do this through a virtual power plant so that we earn income. The virtual power plant knows when it would be more profitable to sell the energy purchased for a specific 30 minutes to the market and continue pumping later. The whole process takes place automatically, following the conditions we set. If the situation requires, we can turn off the service.”

The same flexible energy management solution has been used at Nordkalk's Vasalemma Quarry for several months now, and the second Karinu Quarry pumping station will soon be connected to the virtual power plant.

Flexible equipment management enables to use more renewable energy in the power system and to reduce the environmental footprint of industrial enterprises. Flexibility allows the owner of the device to earn extra income by participating in maintaining the balance of the power system.

Luurmees emphasized that in the current energy market situation with record high prices, companies’ interest in flexible energy management has significantly grown.

“All companies with higher electricity consumption are welcome to contact us, even if it initially seems that this service is not for them,” Luurmees emphasized. “Together, we can analyse the company's processes and equipment, and identify the potential for flexibility. Depending on the device, the earned income can be up to 15% of the annual cost or income of the device consuming or generating electricity. The costs of subscribing to the service are borne by Eesti Energia and your company does not have to make additional investments.”

The virtual power plant is suitable for industries with high energy consumption equipment. Suitable fields: pulp and paper industry, cement industry, cold stores, logistics centres, wood industry, water companies, metallurgy, chemical and plastics industry, cogeneration plants. All of them have equipment whose potential for revenue is still untapped: such as refrigeration and heating equipment, industrial water heaters, furnaces and crushers, the processes of which have inertia that allows the load of these equipment to be shifted from one point in time to another.

In addition to electricity-consuming equipment, it is beneficial to connect production and storage equipment, the operation of which can be quickly redesigned as needed, to the virtual power plant. These include UPS devices, various large batteries, cogeneration plants and generators. It is important that changing the load on a device that consumes or produces electricity does not affect the company's core processes.

How does the system work?

  • First, conditions and restrictions are agreed on how and at what point the company provides its electrical equipment for use in the virtual power plant.
  • Then, a small, book-sized device is installed in the industrial space, starting to interact with the virtual power plant and the electricity market.
  • If necessary, the electrical appliance switches off for a short period to leave the electricity not consumed at that time to the power network. This in turn helps to balance the generation and consumption of electricity in the power network. The service works invisibly.
  • Ask for more:
    Janno Luurmees
    Flexible Energy Management Sales Manager
    Tel.: +372 504 0691
    janno.luurmees@energia.ee