Solution & Technology

Genuinely fossil-free steam for the process industry

Our solution

Power-to-heat thermal energy storage

The Elstor solution is a power-to-heat thermal storage system that enables cost-effective heat and steam production with renewable electricity. Our patented solution is based on optimized remote-controlled energy storage technology that stores electricity as thermal energy.

480–1700 t
carbon dioxide emission reduction with one Elstor basic unit
The emission reduction depends on the capacity, usage, and previously used fuel. Elstor eliminates operational emissions by using clean electrical energy.
95–97 %
Power-to-heat efficiency of Elstor system
Elstor’s device achieves a high efficiency through precisely optimized production and storage charging. Steam production adjusts completely according to the customer’s consumption.
6 months
During operation, Elstor’s device has offset the carbon dioxide emissions resulting from the device’s manufacturing
The CO2 emissions generated during the manufacturing of the device have been offset within approximately six months of use. After this, every saved tonne of CO2 is pure profit.

Clean and emission-free energy

Enables emission-free production processes by utilizing clean energy. Heat and steam production without CO2 and particle emissions.


With storage capacity, energy demand meets the lowest electricity prices of the day. Competitive production costs compared to fossil fuels.

Immediately available technology

The materials and components of Elstor’s solution are sourced from readily available raw materials, extremely durable in lifespan, and fully recyclable.

Calculated based on the usage of our 10 MWh unit. Annual steam production in calculations: 3000 MWh.

Oil-fired boiler

LPG boiler

0 t
CO2 emissions
877 t
CO2 emissions
778 t
CO2 emissions
210 k€
annual running costs
490 k€
annual running costs
310 k€
annual running costs
4-8 years
investment payback period
investment payback period
investment payback period

Don’t you believe? Clean electricity is a cost-effective alternative to fossil fuels, thanks to Elstor’s thermal storage. Contact us, and we will provide you with customized profitability calculations for your system.

How does it work

Charge with inexpensive electricity and use it when needed

Our thermal storage solution efficiently stores electricity during the cheapest hours of the day as thermal energy. The stored energy is used for generating heat and steam. The operating costs of the equipment are competitive with fossil fuels.


Charging with electricity during the lowest price periods

Elstor’s energy storage charging is optimized for the lowest electricity prices throughout the day. An artificial intelligence-based charging algorithm automatically selects the required charging hours by monitoring the storage capacity, upcoming electricity prices, and predicted heat demand

Stored in a patented high-temperature energy storage

Thanks to the storage capacity, the lowest electricity prices and the heat demand of industrial processes align. Due to optimized charging, the operating costs of Elstor’s device are lower than those using fossil fuels

Discharged from storage as heat or steam when needed

Elstor’s device charging and discharging processes are completely independent. This enables flexible use of heat to meet varying needs in industrial processes. The adjustment of the discharge from the storage can be smoothly controlled within the range of 0–100%.


790 t/year
mitigated carbon dioxide emissions


  • Double-unit with 10 MWh storage capacity
  • Has replaced light fuel oil in process steam production
  • Annual emission reductions 790 tonnes
320 t/year
mitigated carbon dioxide emissions

Lappeenrannan Lämpövoima

  • Basic unit with 5 MWh storage capacity
  • Replaces natural gas in production of district heating
  • Annual emission reductions 320 tonnes
< 300 t/year
mitigated carbon dioxide emissions

Kaskein Marja

  • Basic-unit with 5 MWh storage capacity
  • Replaces the usage of natural gas in process steam production
  • Emission reduction potential up to 300 tonnes per year
Elstor logo
340 t/year
mitigated carbon dioxide emissions

Oy Roberts Ab

  • Basic-unit with 5 MWh storage capacity
  • Will replace natural gas in process steam production
  • Annual emission reduction estimated at 340 tons.


Optimized energy storage technology that stores electricity as thermal energy

High discharge power and efficiency makes the Elstor storage system versatile and suitable for a wide range of varying heat and steam needs

The storage capacity does not degrade over time

The storage capacity, as well as the charging and discharging power of Elstor, remain the same year after year. There is no degradation in the storage material over decades of use

Controlled charging and discharging

The charging and discharging process of Elstor’s device can be monitored and controlled remotely. The operation of the device is automated and integrated into the customer’s process.

Efficient storage with low heat losses.

Insulated energy storage minimizes heat losses during the storage phase.

High discharge power and efficiency

Up to 95% efficiency in converting electricity to heat can be achieved. Thanks to the dense storage material and efficient heat transfer, Elstor’s energy storage is capable of high discharge powers.

Modular and mobile

Our system is built from 5 MWh storage elements. The structure is fixed, but it can be moved if necessary.

Real-time system monitoring and autonomous optimization

Our entire process is remotely monitored in real-time. The storage charging autonomously directs to the lowest prices of the day, while discharge is automatically directed according to the customer’s needs.

Technical specifications

High discharge power and efficiency

The charging power of Elstor’s energy storage depends on the storage capacity but can be adjusted to fit the customer’s needs. High discharge power is achieved through dense storage material and efficient heat transfer.

Charging power:

0,5 – 2,5 MW

Storage capacity:

5 – 15 MWh

Discharge power:

Max 2MW

Steam pressure:

Max 16 bar

Steam temperature

Up to 250 C

Charge & Discharge response time:

< 0.5 s

Flexibility range:

0 – 100 %

Frequently asked questions

Our technology is versatile and suitable for various processes.

With Elstor’s 15 MWh unit, it is possible to efficiently cover an annual heat demand of up to 6000 MWh. Technically, the device is capable of even higher consumption, but the benefits of optimization decrease as the consumption becomes excessive.

The payback period is calculated by comparing Elstor’s operating costs to the current heat production method, and therefore, the estimate varies depending on the specific case. Electricity and previous fuel prices vary by location.

The carbon footprint of the device’s manufacturing has been determined, and it is offset within approximately 6 months of the device’s use.

Start by contacting us. The process begins with gathering basic information and by doing profitability calculations for the system tailored to your facility.

Ready for change?

This is how we make your processes fossil-free

Clean electricity, thanks to Elstor’s thermal storage, is a cost-effective alternative to fossil fuels. The technical specifications of the storage may vary by application, but emissions remain zero. Contact us, and we will provide profitability calculations for a customized system tailored to your needs.

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