Energy transition

Loviisan Lämpö Invests in Polar Night Energy's Sand Battery in Pornainen – Towards Non-Combustion Heat Production

Polar Night Energy and Loviisan Lämpö have agreed on the construction of an industrial-scale thermal energy storage. The new 1 MW Sand Battery will be built in Pornainen, integrating with Loviisan Lämpö's district heating network. The thermal energy storage medium will be crushed soapstone, a byproduct of Tulikivi's production of heat retaining fireplaces.

Loviisan Lämpö's CEO Mikko Paajanen and CapMan Infra's Investment Director Sauli Antila with Polar Night Energy's Product Sales Manager Matti Ulvinen and CEO Tommi Eronen (from left to right) at Pornainen district heating plant. The new Sand Battery will be built next to the old district heating plant. PHOTO: Marjaana Malkamäki

See below for Finnish.

Polar Night Energy and the Finnish district heating company, Loviisan Lämpö, have entered into an agreement to build an industrial-scale Sand Battery in Pornainen for Loviisan Lämpö’s district heating network. The heating power of the new Sand Battery is 1 MW and it can store up to 100 MWh of thermal energy, making it about ten times larger than the Sand Battery in operation in Kankaanpää since 2022.

The purpose of the Sand Battery is to reduce carbon dioxide emissions of the district heating production in the Pornainen municipality and introduce a new flexible heat production technology.

"Loviisan Lämpö is moving towards more environmentally friendly energy production. With the Sand Battery, we can significantly reduce energy produced by combustion and completely eliminate the use of oil," says Mikko Paajanen, CEO of Loviisan Lämpö.

The impact of the investment on total emissions is approximately 160 tons of carbon dioxide equivalent per year, translating to nearly a 70% reduction in emissions from the district heating network of Pornainen. In addition to eliminating the usage of oil, the combustion of woodchips is expected to decrease by around 60%.

The municipality of Pornainen is enthusiastic about the new heating method, aligning with its goal of "Towards a Carbon-Neutral Pornainen." Many of the municipality's own buildings, including the Comprehensive School, town hall, and library, rely on district heating.

"Our municipality welcomes all innovative development projects that reduce emissions in district heating operations and contribute to network expansion," says Antti Kuusela, Mayor of Pornainen.

The Sand Battery is flexible in both its electricity usage and district heating production. It is charged from the electric grid using charging algorithms developed by Polar Night Energy, minimizing the cost of electricity used for charging while meeting the heat demand of the district heating network. The thermal energy storage capacity corresponds to almost one-month heat demand in summer and a one-week demand in winter in Pornainen.

"We want to enable the growth of renewable energy. The Sand Battery is designed to participate in all Fingrid's reserve and balancing power markets. It helps to keep the electricity grid balanced as the share of wind and solar energy in the grid increases," says Mikko Paajanen.

Loviisan Lämpö is owned by CapMan Infra fund, a part of the investment company CapMan. CapMan's vision is to be the most responsible private assets investor in the Nordics, committed to creating a sustainable future by addressing climate challenges and utilizing resources efficiently.

"Loviisan Lämpö’s investment in the Sand Battery is a concrete step towards CapMan's climate goals. We are committed to reducing our carbon dioxide emissions and seeking solutions that lead us towards net-zero emissions, of which this innovative solution is an excellent example," says Sauli Antila, Investment Director at CapMan Infra.

Polar Night Energy will deliver the Sand Battery to Loviisan Lämpö as a turnkey project. The Sand Battery will be approximately 13 meters high and 15 meters wide. The estimated duration for construction and testing is around 13 months. The project has received support from Business Finland's new technology energy aid.

"It's exciting to build a large-scale thermal energy storage, which will also act as a primary production plant in Pornainen's district heating network. This is a significant step in scaling up the Sand Battery technology," says Liisa Naskali, COO at Polar Night Energy.

Polar Night Energy's CEO Tommi Eronen and Loviisan Lämpö's CEO Mikko Paajanen planning the new Sand Battery for Pornainen district heating network. PHOTO: Marjaana Malkamäki

The Sand Battery in Pornainen Will Have Tulikivi’s Crushed Soapstone as the Storage Medium – a Choice That Promotes Circular Economy

Loviisan Lämpö's new thermal energy storage will use crushed soapstone produced as a byproduct of Tulikivi's manufacturing process. Tulikivi is the market leader in heat retaining fireplaces in the world.

"Collaborating with Polar Night Energy is an interesting venture into new business, leveraging the traditional strengths of soapstone, such as excellent heat conduction and retention properties. This collaboration supports Tulikivi's goals of maximizing the utilization of raw materials," says Heikki Vauhkonen, CEO of Tulikivi.

Sand Batteries can use sand or sand-like materials as the storage material. Soapstone conducts heat better than conventional sand. According to research conducted by Polar Night Energy and Tulikivi, soapstone is an excellent choice for Loviisan Lämpö’s Sand Battery due to its unique properties.

"We always choose the thermal energy storage medium based on the customer's needs. Examining and testing different materials is crucial for us to use materials that are suitable in terms of properties, cost-effectiveness, and promotion of circular economy," says Liisa Naskali of Polar Night Energy and adds, "Tulikivi is a well-known and traditional company. The soapstone they use is a very Finnish thing. It's great to collaborate with Tulikivi."

"This collaboration supports Tulikivi's goals of maximizing the utilization of raw materials," says Heikki Vauhkonen, CEO of Tulikivi.

About the companies

Loviisan Lämpö is a Finnish district heating company that supplies district heating to its customers in Loviisa, Pukkila, Pornainen, Pyhtää Siltakylä, Pyhtää village center, and Lappohja. Loviisan Lämpö is owned by CapMan Infra.

CapMan is a leading Nordic private asset expert with an active approach to value creation. We have developed hundreds of companies and real estate assets and created substantial value in these businesses and assets over the past 30 years. We have over €5 billion in assets under management and our investment strategies cover real estate and infrastructure assets, natural capital and minority and majority investments in portfolio companies.

Tulikivi is the market leader in heat retaining fireplaces in the world. Tulikivi was born by combining Finnish knowledge of arctic conditions, wood heating know-how and a unique soapstone reserve.

Polar Night Energy is a Finnish startup that designs and manufactures high temperature thermal energy storages for wind and solar energy. The Sand Battery developed by the company enables a significant increase in wind and solar energy production while reducing the use of fossil fuels. The company was founded in 2018.

Press photos and interview requests:

Miika Peltola
Communications Manager
miika.peltola@pne.fi


Loviisan Lämpö investoi Pornaisissa Polar Night Energyn hiekka-akkuun – Matkalla kohti polttamatonta lämmöntuotantoa

Polar Night Energy ja Loviisan Lämpö ovat sopineet lämpöenergiavaraston rakentamisesta. Uusi 1 MW hiekka-akku rakennetaan Pornaisiin Loviisan Lämmön kaukolämpöverkolle. Lämpöenergiavaraston väliaineena käytetään Tulikiven varaavien tulisijojen tuotannon sivuvirtana syntyvää vuolukivimursketta.

Polar Night Energyn tuotemyyntipäällikkö Matti Ulvinen ja toimitusjohtaja Tommi Eronen yhdessä Loviisan Lämmön toimitusjohtajan Mikko Paajasen ja CapMan Infran sijoitusjohtajan Sauli Antilan kanssa Pornaisissa. Uusi hiekka-akku rakennetaan vanhan kaukolämpölaitoksen viereen. KUVA: Marjaana Malkamäki

Polar Night Energy ja kotimainen kaukolämpöyhtiö Loviisan Lämpö ovat sopineet teollisen mittakaavan hiekka-akun rakentamisesta Pornaisiin Loviisan Lämmön kaukolämpöverkolle. Uuden hiekka-akun teho on 1 MW ja varastointikapasiteetti 100 MWh. Se on noin kymmenkertainen vuodesta 2022 Kankaanpäässä toimineeseen hiekka-akkuun verrattuna.

Hiekka-akun tavoitteena on Pornaisten kunnan alueella toimivan kaukolämpöverkon lämmöntuotannon hiilidioksidipäästöjen vähentäminen ja uudentyyppisen joustavan lämmöntuotantoteknologian käyttöönotto.

”Loviisan Lämpö etenee kohti ilmastoystävällisempää energiantuotantoa. Hiekka-akun avulla voimme merkittävästi vähentää polttamalla tuotettua energiaa ja luopua kokonaan öljyn käyttämisestä”, sanoo Loviisan Lämmön toimitusjohtaja Mikko Paajanen.

Investoinnin vaikutus kokonaispäästöihin on noin 160 hiilidioksidiekvivalenttitonnia (t CO2e) vuodessa, mikä tarkoittaa lähes 70 prosentin päästövähennystä Pornaisten kaukolämpöverkossa. Öljystä luopumisen lisäksi hakepolttoaineen käyttö vähenee noin 60 prosenttia.

Myös Pornaisten kunta on innoissaan uudesta lämmitysmuodosta. Yksi Pornaisten kuntastrategian päämääristä on ”Kohti hiilineutraalia Pornaista”. Suuri osa kunnan omista rakennuksista on kaukolämmössä, kuten Yhtenäiskoulu, kunnantalo ja kirjasto.

”Kuntamme toivottaa tervetulleiksi kaikki kaukolämpötoiminnan päästöjä vähentävät, innovatiiviset kehityshankkeet ja verkon laajentamisen”, sanoo Pornaisten kunnanjohtaja Antti Kuusela.

Hiekka-akku on joustava sekä sähkö- että kaukolämpöverkon suuntaan. Hiekka-akkua ladataan sähköverkosta Polar Night Energyn kehittämän latausalgoritmin mukaan siten, että lataukseen käytettävän sähkön hinta minimoidaan ja samalla kaukolämmön tulevat lämmöntarpeet pystytään täyttämään. Lämpövaraston kapasiteetti vastaa kesäaikaan vajaan kuukauden ja talvella vajaan viikon lämmön tarvetta Pornaisissa.

”Haluamme olla mahdollistamassa uusiutuvan energian kasvua. Hiekka-akusta tehdään sen kokoinen, että sillä voi osallistua myös kaikille Fingridin reservi- ja säätösähkömarkkinoille. Hiekka-akku auttaa pitämään sähköverkkoa tasapainossa, kun tuuli- ja aurinkoenergian osuus verkossa kasvaa”, sanoo Mikko Paajanen.

Loviisan Lämmön omistaa pääomasijoitusyhtiö CapManiin kuuluva CapMan Infran rahasto. CapManin visiona on olla vastuullisin pääomasijoittaja Pohjoismaissa. Yritys on sitoutunut luomaan kestävää tulevaisuutta vastaamalla ilmastohaasteisiin sekä hyödyntämällä resursseja tehokkaasti.

”Loviisan Lämmön tekemä investointi hiekka-akkuun on konkreettinen askel kohti CapManin ilmastotavoitteita. Olemme sitoutuneet vähentämään hiilidioksidipäästöjämme ja etsimään ratkaisuja, jotka vievät meitä kohti nettonollapäästöjä, ja joista tämä innovatiivinen ratkaisu on erinomainen esimerkki”, sanoo CapMan Infran sijoitusjohtaja Sauli Antila.

Polar Night Energy toimittaa hiekka-akun Loviisan Lämmölle avaimet käteen -toimituksena. Hiekka-akusta tulee noin 13 metriä korkea ja 15 metriä leveä. Hiekka-akun rakentamisen ja testaamisen arvioitu kesto on noin 13 kuukautta. Projekti on saanut Business Finlandin uuden teknologian energiatukea.

”On hienoa päästä rakentamaan suurta teollisen mittakaavan lämpövarastoa, joka tulee vieläpä toimimaan primäärituotantolaitoksena Pornaisten kaukolämpöverkossa. Tämä on iso askel hiekka-akkuteknologian skaalaamisessa”, sanoo Polar Night Energyn operatiivinen johtaja Liisa Naskali.

Pornaisten hiekka-akun väliaineena käytetään Tulikiven sivuvirtakiveä – Valinta edistää kiertotaloutta

Loviisan Lämmön uuden lämpöenergiavaraston väliaineena tullaan käyttämään Tulikiven tuotannon sivuvirtana syntyvää vuolukivimursketta. Tulikivi on varaavien tulisijojen markkinajohtaja maailmassa.

”Yhteistyö Polar Night Energyn kanssa on mielenkiintoinen avaus uuteen liiketoimintaan, jossa hyödynnetään vuolukiven perinteisiä vahvuuksia, kuten hyviä lämmönjohto- ja varausominaisuuksia. Yhteistyö tukee Tulikiven tavoitteita raaka-aineen mahdollisimman korkeasta hyödyntämisestä”, sanoo Tulikiven toimitusjohtaja Heikki Vauhkonen.

Hiekka-akuissa voi käyttää lämmönvarastointimateriaalina joustavasti erilaisia hiekan kaltaisia materiaaleja. Vuolukivimurske johtaa tavanomaista hiekkaa paremmin lämpöä. Polar Night Energyn ja Tulikiven tekemien tutkimusten perusteella vuolukivimurske sopii ominaisuuksiensa takia erinomaisesti käytettäväksi Loviisan Lämmön hiekka-akussa.

”Valitsemme väliaineen aina asiakkaan tarpeiden mukaan. Erilaisten materiaalien tutkiminen ja testaaminen on meille tärkeää, jotta pystymme käyttämään materiaaleja, jotka ovat ominaisuuksiltaan sopivia, kustannustehokkaita ja kiertotaloutta edistäviä”, sanoo Polar Night Energy Liisa Naskali ja lisää:

”Tulikivi on tunnettu ja perinteinen yritys. Heidän käyttämänsä vuolukivi on hyvin suomalainen juttu. On hienoa tehdä yhteistyötä Tulikiven kanssa.”

Lisätietoa yrityksistä

Loviisan Lämpö on kotimainen kaukolämpöyhtiö, joka toimittaa kaukolämpöä asiakkaalleen Loviisan, Pukkilan, Pornaisten, Pyhtään Siltakylän, Pyhtään kirkonkylän sekä Lappohjan alueilla. Loviisan Lämpö Oy:n omistaa CapMan Infra.

CapMan on johtava pohjoismainen aktiivista arvonluontityötä tekevä pääomasijoittaja. Olemme kehittäneet satoja yhtiöitä ja kiinteistöjä ja luoneet merkittävää arvoa yli kolme vuosikymmentä. Hallinnoimme yhteensä yli 5 miljardin euron pääomia ja sijoitusalueemme kattavat kiinteistö-, infrastruktuuri- ja luonnonvarasijoittamisen, sekä vähemmistö- ja enemmistösijoitukset kohdeyhtiöihin.

Tulikivi on varaavien tulisijojen markkinajohtaja maailmassa. Tulikivi on syntynyt yhdistämällä suomalainen arktisten olosuhteiden tuntemus, puulämmitysosaaminen ja ainutlaatuinen vuolukivivaranto.

Polar Night Energy on tamperelainen startup-yritys, joka suunnittelee ja valmistaa korkean lämpötilan energiavarastoja tuuli- ja aurinkoenergialle. Yrityksen kehittämä hiekka-akku mahdollistaa tuuli- ja aurinkoenergian voimakkaan lisäämisen ja fossiilisten polttoaineiden käytön vähentämisen. Yritys on perustettu 2018.

Kuva- ja haastattelupyynnöt

Miika Peltola
Viestintäpäällikkö
miika.peltola@pne.fi

Empowering the Energy Transition: The Sand Battery's Impact on Heating Costs

Ever wondered how thermal energy storages, like Polar Night Energy’s sand battery, can help save on heating expenses? We'll walk you through a simple real-world example that demonstrates their cost-saving power.

Energy storage is vital for the energy transition, but did you know that thermal energy storages can also significantly reduce heating costs compared to traditional sources such as natural gas, oil, coal, biomass or even heat pumps?

Case: Spa and its heating system, Finland

Energy storage: Polar Night Energy’s 2 MW thermal energy storage with a capacity of 200 MWh

Heat demand: Constant 500 kW

Time period: 16/8/2023 – 15/9/2023

Total heat needed during the period: 372 MWh

Electricity contract: electricity with spot pricing, per hourly market price

Costs: The sand battery is charged with electricity when spot prices are low, avoiding peak hours. This approach results in significantly lower costs compared to both direct electricity (average of spot price) and traditional combustion methods.

The following table shows the heating costs using different energy sources (without tax). The 'PNE spot' refers to the final price for purchased electricity used to charge the sand battery.

Table Example
Source Heat price EUR/MWh Total cost EUR
PNE spot 11 4,170
Direct electricity 86 30,980
Heat pump (COP 2.5) 34 12,390
District heating 90 32,450
Natural Gas 70 25,240
Oil 125 45,060

If you want to see how PNE spot is formed, keep reading!

Method: There are two important parameters for the sand battery:

  • Charging power versus heat demand (share of charging hours)

  • Capacity (time scale for charging)

In this case, the storage has 2 MW charging power, and the heat demand is constantly 0.5 MW. That is, we need to charge 25% of all hours.

With this heat demand, the natural time range for the storage is 15 days.

Hence, from every 15-day slot, the storage must charge 25% of the time to fulfil the heat demand. In this simple computation, we get the price 11 EUR/MWh with the following procedure:

  1. Divide the time to 15-day slots,

  2. from each slot, choose 25% * 15 days = 181 cheapest hours and

  3. compute the average spot price for the chosen hours. This is the final ‘PNE spot’.

The figure 1 illustrates the charging cost of the sand battery over time. During 75% of the time, the sand battery is not charged, with PNE spot at 0 EUR/MWh. In the remaining 25% of hours, PNE spot mirrors the spot price, resulting in peaks in the PNE spot curve. The highest spot prices are effectively avoided.

Figure 1. The charging cost of the sand battery over time.

The greater the charging power is compared to the heat demand and the greater the capacity is, the lower the PNE spot price will be. Fewer charging hours allow us to focus on cheaper times, while greater capacity provides more flexibility in selecting charging hours.

Keep in mind that when calculating the cost of produced heat, it's necessary to adjust the prices using the efficiency coefficient, which can reach up to 95% for our heat storage. You can find more details in our Lead Scientist's blog article.

Furthermore, the sand battery's flexible electricity usage enables participation in grid balancing markets, potentially reducing your heating costs significantly. Curious to learn more? Stay tuned for our upcoming post on FCR and FRR markets!

The Next Step: A Feasibility Study

The calculation above is a simplified representation of a basic use case. Interested in a thorough and transparent analysis of your energy system, complete with realistic simulations and intelligent charging algorithms? Our feasibility study evaluates your system's needs, including local energy production and storage, for optimal performance.

Visit our Solutions page for details!

Text: Terhi Moisala, Data Scientist

Sources for energy prices: Finnish day-ahead electricity prices, ENTSO-E Transparency Platform, Statistics Finland


This article was conducted under the project NewSETS – New energy storages promoting sustainable energy transition in societies.

This project has received funding in the framework of the joint programming initiative ERA-Net Smart Energy Systems’ focus initiatives Smart Grids Plus and Integrated, Regional Energy Systems, with support from the European Union’s Horizon 2020 research and innovation programme under grant agreements No 646039 and 775970.

The content and views expressed in this material are those of the authors and do not necessarily reflect the views or opinion of the ERA-Net SES initiative. Any reference given does not necessarily imply the endorsement by ERA-Net SES.

Polar Night Energy’s Sand Battery Doesn’t Cause Sand Shortage – Thermal Energy Storage Medium Explained

Yes, the world might face shortage of sand. No, the sand battery won’t make the problem worse. Polar Night Energy’s Data Scientist explains how the sand battery is a perfect match for circular economy.

Polar Night Energy’s sand battery is a high temperature thermal energy storage that uses sand or sand-like materials as its storage medium. It stores energy in sand as heat.

We use sand because it allows a wide temperature range with storage time from hours to months. It is also affordable, non-toxic and can be locally sourced.

Meanwhile, we are about to face a crisis of sand shortage. Extraction of sand is an enormous unregulated business and rarely sustainable. (1)

We have been asked whether our technology is only making the problem worse. The short answer is no, and the next four points explain why.

1. The sand battery can use all sorts of sand

Sand is a key element in concrete, and hence vital for modern construction. A good quality concrete requires sand which has certain grain size distribution and shape, which is why sand is extracted even from coastal ecosystems rather than deserts.

However, our technology is flexible: the sand battery can use sand with varied mineral composition, very wide range of grain size distributions, and no restrictions to microscopic characters of the sand grains. This enables the usage of materials that are locally and commonly available, or even considered as waste.

We like high density, low-cost materials that are not from scarce sources. Someone else’s dirt could be our heat storage medium.

2. Mine waste volumes are overwhelming

Most of the substance extracted in mines needs to be disposed of. Only a small fraction of the material is utilized, and the rest is left to lie in heaps. Since mines can operate for decades, they are often accompanied with mountains of waste rock in their backyards.

In many cases this waste could be used to store energy in our sand batteries. And believe me, there are enough of heaps to build all the sand batteries we need.

Based on the estimate of Mission Innovation, 737 TWh of energy will need storage in 2030. (2) Let’s imagine that we would store all that energy in our sand batteries (a silly thought, since even if a sand battery is great for many applications, it can never fulfill all the storing needs. Imagine a few tons of sand battery in the trunk of your Tesla!).

Nevertheless, building all these sand batteries would require 200 million tons of sand or sand-like material, and the sand batteries would serve for decades. For comparison, 500 million tons of mining waste was produced only in EU during the year 2020. (3)

3. Mining industry seeks ways to direct mine waste streams into usage – we are happy to help

Mine waste is not only poorly utilized but causes many problems from land usage to soil contamination. The mining industry is now looking for solutions to this environmental hazard: ever larger portion of the wall rock streams is directed to circular economy, and we are actively searching opportunities to collaborate.

Mine waste volumes are too large for our sand batteries to completely tackle this problem, but we can do our part. At very least, no new mines are needed to fill sand batteries.

4. Our system is robust and safe

The design life of the storage is tens of years. All the materials used in construction of the system are recyclable and non-toxic. Even the storage medium will be reusable.

As our sand battery can be connected to existing infrastructure, building a combustion-free solution is straightforward and cost-effective.

To mitigate climate change, we desperately need solutions to store energy from weather dependent renewable sources, such as solar and wind. If we want these solutions to thrive, they need to be environmentally and socially sustainable as well as economically viable – like our sand battery.

Or as Donald Sadoway puts it: “If you want to make something dirt-cheap, make it out of dirt. Preferably dirt that’s locally sourced.” (4)

Text: Terhi Moisala, Data Scientist


Sources:

1 UNEP: Our use of sand brings us “up against the wall”, says UNEP report

2 Mission Innovation: Sand-Based High Temperature Seasonal Heat Storage by Polar Night Energy Oy, Avoided Emissions Framework – Level 2 version 0.8 assessment, 2020

3 Eurostat: Waste statistics

4 TED: Reinventing the battery: Donald Sadoway at TED2012


This article was conducted under the project NewSETS – New energy storages promoting sustainable energy transition in societies.

This project has received funding in the framework of the joint programming initiative ERA-Net Smart Energy Systems’ focus initiatives Smart Grids Plus and Integrated, Regional Energy Systems, with support from the European Union’s Horizon 2020 research and innovation programme under grant agreements No 646039 and 775970.

The content and views expressed in this material are those of the authors and do not necessarily reflect the views or opinion of the ERA-Net SES initiative. Any reference given does not necessarily imply the endorsement by ERA-Net SES.