On paper, the Donut Lab battery sounds amazing: full charge in less than 10 minutes, 400 Wh/kg energy density, 100,000 charge cycles, extremely safe and low cost. Basically it ticks every single box on a battery wish list. The problem on those promises is that this is all based on Donut’s own claims.

Donut Lab’s Solid-State Battery: Breakthrough or Battery Hype Cycle 2.0?

If you follow battery tech even casually, you’ve probably seen the headlines: a Finnish startup, Donut Lab, claims to have a “production-ready solid-state battery” with specs that read like a wish list from every EV (electric vehicle) engineer on the planet.

We’re talking following promises:
* 5–10 minute full charge
* ~400 Wh/kg energy density
* Up to 100,000 charge cycles
* Improved safety
* Lower cost than current lithium-ion

On paper, that’s not just incremental improvement — those are disruptive (if they are true). But here’s the thing: for technically minded readers, those numbers immediately raise eyebrows.

The Spec Sheet That Breaks Physics?

Solid-state batteries are real. Replacing liquid electrolyte with a solid one *can* enable higher energy density and better safety margins. No argument there. The industry has been chasing this for over a decade.

But combining:

* Ultra-fast charging
* Extremely high cycle life
* High energy density
* Low cost
* Immediate production readiness

…in a single chemistry? That’s where skepticism kicks in.

Hackaday’s deep dive into the Donut battery claims points out a core issue: when you try to reconcile those parameters with known electrochemistry and materials science, the puzzle pieces don’t fit together. Trade-offs are fundamental to battery design. High energy density tends to stress cycle life. Fast charging increases thermal and structural degradation. Solid electrolytes introduce interface challenges and manufacturing complexity.

Typically with battery chemistry you don’t get everything at once. At least, not with any chemistry currently understood. Even a professor from Aalto University publicly stated that parts of the claims would “break the laws of physics” if true. That’s not casual criticism — that’s a red flag.

Where’s the Data?

Another sticking point for engineers: there’s no publicly available technical documentation.

No patents detailing the breakthrough.
No peer-reviewed papers.
No independent lab validation.
No disclosed chemistry.

What exists is a launch video from CES and bold statements about production already happening in Finland.

Yet when journalists asked where the factory is located, the response was essentially: “No comment.” For a claimed production-ready technology in a €200 billion global battery market, that’s unusually opaque.

Industry Reaction: From Skepticism to Panic

The response hasn’t just been academic skepticism.

Yang Hongxin, chairman of Svolt (a major Chinese battery player), reportedly called the claims “a fraud,” stating the parameters are internally contradictory and that industrialization of all-solid-state batteries is still premature.

That’s strong language — but it reflects a broader sentiment in the industry. Many battery veterans see the announcement as part of a familiar pattern: Company announces revolutionary solid-state breakthrough → promises production in two years → timeline quietly slips → repeat.

We’ve seen this cycle before.

And yet — interestingly — Donut Lab’s announcement triggered something real: competitors accelerated their own announcements. In that sense, whether the battery exists or not, the marketing worked brilliantly. It pushed the conversation forward.

The Verge Connection Raises More Questions

Adding complexity, Donut Lab is connected to Verge Motorcycles, which has announced bikes using this battery tech. But financial reports related to Verge have painted a messy picture, and delivery timelines for the motorcycles have reportedly slipped.

For engineers evaluating credibility, financial instability and delayed hardware launches don’t inspire confidence in breakthrough battery mass production.

Meanwhile, Sodium-Ion Creeps Forward

While the spotlight is on “miracle” solid-state cells, sodium-ion batteries are quietly gaining traction. Lower energy density, yes — but cheaper materials, better cold performance, and realistic manufacturing pathways.

For Nordic climates, sodium-ion might be the more pragmatic near-term solution. It’s not as sexy as a physics-defying supercell. But it’s real.

So… Breakthrough or Vaporware?

Here’s the balanced take:

If Donut Lab’s claims are even partially true, this would be one of the most significant battery breakthroughs in decades — potentially reshaping China’s dominance in the sector and redefining EV economics.

But extraordinary claims require extraordinary evidence.

Until we see:
* Independent validation
* Clear chemistry disclosure
* Real production lines
* Shipped products in customer hands

…it remains a fascinating case study in how hype, capital markets, and deep-tech ambition intersect.

For engineers and technically minded observers, the right stance isn’t cynicism — it’s disciplined skepticism.

Because if history has taught us anything about batteries, it’s this: The laws of electrochemistry don’t bend for press releases.

Sources:

Donut Labin omistaja jakoi optioita pilkkahinnalla – Holdingyhtiön osakkeen arvoksi määriteltiin vain 69 senttiä
https://www.talouselama.fi/uutiset/a/b2e4e604-195c-4a59-9e19-ba8ca81efabd

Investigating The Science Claims Behind The Donut Solid State Battery
https://hackaday.com/2026/02/08/investigating-the-science-claims-behind-the-donut-solid-state-battery/

Kommentti / Oli Donut Labin akusta mitä mieltä tahansa, Kiinassa on painettu paniikkinappulaa
https://www.kauppalehti.fi/uutiset/a/8d56c5cd-79c1-47c1-b515-c4c77fe5a98d

Donut Labiin kytkeytyvän Vergen raportti on karua luettavaa – Toimitusjohtajalla on selitys kaikkeen
https://www.kauppalehti.fi/uutiset/a/f942fca5-d7e1-4629-b7aa-2c0ed130c146

Vergen moottoripyörien toimitusaika venähti – Näin kommentoi toimitusjohtaja
https://www.kauppalehti.fi/uutiset/a/5460f06d-27b5-4c8e-bb7f-8fc03f5294f5

Unohda Donut Lab – Nyt tulevat Suomeen sopivat suola-akut
https://www.kauppalehti.fi/uutiset/a/16bffade-4c55-41af-a844-46cef04c16d5

Suomalainen startup väittää keksineensä superakun – professori tyrmistyi lupauksista: ”Rikkoisi fysiikan periaatteita”
https://yle.fi/a/74-20204751

Donut Labin ihmeakun lanseeraukseen liittyvän Verge Motorcyclesin tilintarkastus paljasti kaaoksen
https://yle.fi/a/74-20205916

Donut Labin toinen perustaja vakuuttaa CES-haastattelussa
https://etn.fi/index.php/13-news/18415-donut-labin-toinen-perustaja-vakuuttaa-ces-haastattelussa

Professori: Suomalaisen ihmeakun teknologia voisi horjuttaa Kiinan ylivoimaa, jos väitteet siitä pitävät paikkansa
https://yle.fi/a/74-20206158

Missä se Donut Labin akkutehdas oikein piileskelee? – ”Emme kommentoi”
https://tekniikanmaailma.fi/missa-se-donut-labin-akkutehdas-oikein-piileskelee-emme-kommentoi/

Donut Labin akkusensaatio – totta vai tarua?
https://tekniikanmaailma.fi/donut-labin-akkusensaatio-totta-vai-tarua/

GWM’s Svolt CEO calls Donut Lab’s ‘production-ready’ solid-state battery a fraud
https://carnewschina.com/2026/01/20/gwm-spin-off-svolt-ceo-claimed-donut-labs-production-ready-all-solid-state-battery-is-a-fraud-report-says/

Teknologia 2025 event highlights included increased visitor and exhibitor numbers, with a strong focus on smart and sustainable industry, safety, AI, and the hydrogen economy.

Cyber Security Nordic brought together the leading industry players in the cyber security. The event was tailored for IT and ICT executives, cybersecurity experts, as well as private and public sector executives, decision-makers, and government officials responsible for cybersecurity.

Article links (in Finnish):
https://www.uusiteknologia.fi/2025/11/04/helsingin-teknologiamessut-alkaa-nailla-ohjeilla-selviat/
https://www.uusiteknologia.fi/2025/11/07/tekoaly-tuli-teknologiamessuille/
https://www.uusiteknologia.fi/2025/11/06/kyberturva-houkutti-kasvavasti-tietoturva-ammattilaisia/
https://www.uusiteknologia.fi/2025/11/06/teknologia25-palautumista-useilla-hyvinvointitekniikoilla/
https://www.uusiteknologia.fi/2025/11/03/uusia-reunalaskenta-ja-tekoalyratkaisuja/

Over the past year, these robots have become a familiar sight, delivering over 150 000 orders. In total the robots have made over 350,000 deliveries to customers and traveled a million kilometers in Finland. In Finland, Starship’s transport robots started operating in Otaniemi, Espoo, in April 2022. Finland has introduced rules for the use of small transport robots in public transport.

Although it only snows in the capital region from time to time, the robots have survived quite well during the test periods on the streets, even on icy surfaces and over large puddles. The robots use GPS tools and artificial intelligence to plan routes and learn the operating environment.

The robots are from Estonian-based ten years old company Starship Technologies. Starship Technologies develops battery-powered robots in Finland as well as Estonia. The headquarters are in the United States. Starship’s food robots have already traveled 15 million kilometers and made more than seven million autonomous deliveries around the world.

Starship’s robots have 12 cameras, ultrasonic sensors and radar, and use computer vision to detect obstacles. Robots are almost completely autonomous. The robot uses the latest computer vision and GPS positioning to navigate. Although the robots travel autonomously 99 percent of the time, and a human can take control of them at any time. The robots have also a voice feature that allows it to communicate with those nearby.

A large part of our product development for robot technology and transport services has been done in Finland. The appearance of the robots has also been designed by the Finnish company Aivan. Finns designed a robot that is treated like an animal. Designer Antti Mäkelä says that the robots have been designed to be humane, sweet and approachable in order to protect them from vandalism.
“According to Mäkelä, it has been essential in the design of the robot that the 12 cameras located in the front of it have been hidden. In terms of the experience of friendliness and innocence, it is important that people do not feel that they are being snooped on.” – The essential thing is probably that when people are eavesdropped on, they don’t know it and therefore don’t feel that way.

Videos:

Starship Robots in the Finnish Winter
https://www.youtube.com/watch?v=LKg3WFlKz4U

How Alepa Food Delivery Robots are replacing human workers in Espoo, Finland.
https://www.youtube.com/watch?v=cKI09vTf6d4

How a Robot Delivers Grocery in Finland! Amazing!
https://www.youtube.com/watch?v=AS8fx4JRCF4

A Day in the Life of a Starship Robot
https://www.youtube.com/watch?v=Z417CncwQsg

Inside Starship Delivery Robots
https://www.youtube.com/watch?v=1GpaAF3_lKA

Sources:
https://www.uusiteknologia.fi/2025/02/13/starshipin-robotit-vievat-jo-woltin-ruuatkin/
https://www.uusiteknologia.fi/2024/12/18/konenako-helpottaa-kuljetusrobottien-toimintaa/
https://www.starship.xyz/
https://www.uusiteknologia.fi/?s=Starship
https://yle.fi/a/74-20138076
https://en.wikipedia.org/wiki/Starship_Technologies
https://www.helsinkitimes.fi/finland/finland-news/domestic/25222-finnish-grocery-chain-expands-robotic-delivery-to-over-100-stores-by-year-end.html

Bonus video how to make your own:
Building a Delivery Robot (controlled by Live Chat) using Raspberry Pi 4 | Droiid
https://www.youtube.com/watch?v=LdV8n915Vwk

Finnish authorities board a ship in the Baltic Sea that the West suspects is linked to Russia, a day after an underwater Finland-Estonia electricity cable was cut and several telecom fiber optic cables were damaged.

Lloyd’s List on-line magazine claims that Russia-linked cable-cutting tanker seized by Finland ‘was loaded with spying equipment’

The incident has intensified fears in Europe over a Russian hybrid war targeting critical infrastructure in the Baltic and beyond. Estonia navy to protect undersea power link after main cable damaged.

Sources:
https://www.lloydslist.com/LL1151955/Russia-linked-cable-cutting-tanker-seized-by-Finland-was-loaded-with-spying-equipment
https://www.nytimes.com/2024/12/26/world/europe/finland-estonia-cables-russia.html
https://www.theguardian.com/world/2024/dec/25/finland-estonia-power-cable-hit-in-latest-baltic-sea-incident
https://yle.fi/a/74-20133531
https://www.bbc.com/news/articles/c1elq7lx9qdo
https://www.aljazeera.com/news/2024/12/27/did-a-russian-shadow-ship-cut-the-finland-estonia-undersea-baltic-cable

Commissioned from composer Lauri Porra, the soundscape consists of 15 compositions inspired by the country, its people and their characteristics.

https://www.helsinkitimes.fi/finland/finland-news/domestic/25860-finland-becomes-world-s-first-country-to-launch-national-soundscape.html

“This understated, minimalist music is meant to create a certain atmosphere,”

https://finland.fi/soundscape/

Recycling plastic is complex. There are many different types of plastic made from many different types of resins and processed differently during manufacturing of packages. Common plastics such as PET (Polyethylene Terephthalate), HDPE (High-Density Polyethylene), PVC (Polyvinyl Chloride), LDPE (Low-Density Polyethylene), PP (Polypropylene), and others need to be sorted into distinct categories for the recycling to work. Some plastic types can be recycled better than other. For those easy to recycle plastic types plastic is typically first cleaned to remove contaminants, shredded or granulated into small pieces, melted, formed into pellets or granules. Those pellets of granules can be used to make new plastic products.

There are various challenges is plastic recycling, and in many locations it does not work too well. But there are is one recycling that works well in some countries: plastic bottle recycling. The first polyethylene terephthalate (PET) disposable soda bottle was introduced back in 1975. Creating a lightweight disposable bottle was more convenient for businesses as they do not break as easily as glass bottles and are lighter to transport, saving energy. A wide range of drinks, food products and other consumer goods are bottled in PET. The majority of bottles contain water or soft drinks, both still and carbonated.

The plastic packaging and beverage industry was encouraging recycling initiative, but in many places they are not widely recycled. All types of PET packaging, including bottles are usually marked with the recycle symbol 1.

There have been claims that plastic bottles cannot be recycled into new plastic bottles. Although this might have been largely true in the past, this is changed. Nowadays plastic bottles can be recycled, and they are recycled successfully in some countries. Although plastic bottle recycling certainly can reduce waste, in many countries lots of plastic is going to landfills. Just because a plastic bottle has recycling arrows on the bottom doesn’t actually mean it is recyclable in a given area.

Some countries have legislated a deposit for packaging including PET bottles. In the EU, deposit schemes average an 86% recovery rate. In Finland there is a DEPOSIT-BASED SYSTEM for plastic bottles, glass bottles and cans. There is return rate of more than 90%. In Finland 460 million plastic bottles are returned every year. In Finland plastic bottles are converted to PET plastic raw material (small plastic balls). This material is used to make new plastic bottles, food packages and other plastic products. Here is an example of Coca Cola bottle that is made 100% from recycled PET.

Finland’s system for returning beverage containers started in the 1950s, and today almost every bottle and can is recycled. The development of a bottle return system began in Finland with the arrival of Coca-Cola bottles at the 1952 Olympic Games. Today, 65 years later, Finland has the world’s best bottle deposit and return system – thanks to the model administered by Palpa. The system is based on a deposit: a fee that is returned to the consumer when they return a bottle or other drinks packaging.

Convenience is the cornerstone of the system’s success in Finland. Finnish residents returned more than two billion bottles and cans in 2020, 93 percent of the total amount purchased in the country. The factors that make this possible include automated bottle-return machines developed decades ago and the expansion of the system to include plastic bottles in the 2000s. Every time a person buys a beverage in a bottle or can, they pay a deposit of 15 to 40 cents. The system covers alcoholic beverages, soft drinks and bottled water, in aluminium cans, glass bottles and bottles made from PET plastic. People return most of the bottles they have. On average, every Finn returns 373 items in a year: 251 aluminum cans, 98 plastic bottles and 24 glass bottles. Any bottles that someone happens to leave behind on the street or in a park are snapped up by someone who returns them for the deposit money. Palpa’s turnover amounts to about 80 million euros, generated from material sales, recycling fees and charges for nonreturnable packaging.

In other Nordic Countries, beverage packages are recycled with the help of a national and general deposit-based system, as in Finland. Return rates are also high. Now a new EU Directive threatens Finland’s bottle return system that works very well. A new EU directive aimed at tackling plastic waste may lead to major changes to Finland’s bottle return system, according to Palpa, the company responsible for the collection, recycling and reuse of beverage packages. The directive requires that caps are connected to bottles at all stages of the product life cycle.

In USA there was some recycling activities also. It was time when CarbonLITE Industries recycled more than 2 billion PET bottles into food-grade post-consumer PET was one of the largest producers of food-grade recycled PET in the world. Then it went to bankruptcy in spring 2021.

Links:

https://hackaday.com/2022/01/15/recycling-soda-bottles-into-filament-to-print-smaller-soda-bottles/

https://www.is.fi/taloussanomat/art-2000009098655.html

https://www.muovikuuluukiertoon.fi/kierratysvinkit/

https://www.hsy.fi/jatteet-ja-kierratys/jateopas/jatteet/muovipakkaus/

https://finland.fi/life-society/circular-economy-success-finlands-recycling-programme-keeps-bottles-and-cans-off-the-streets/

https://en.wikipedia.org/wiki/PET_bottle_recycling

https://finland.fi/life-society/circular-economy-success-finlands-recycling-programme-keeps-bottles-and-cans-off-the-streets/

https://www.palpa.fi/beverage-container-recycling/deposit-refund-system/

https://yle.fi/aihe/artikkeli/2019/05/02/kirkas-muovipullo-voi-kiertaa-ikuisesti-varilliset-pullot-eivat-kierra-samalla

https://yle.fi/uutiset/osasto/news/eu_directive_threatens_finlands_bottle_return_system/11062302

https://finland.fi/life-society/finnish-families-get-to-grips-with-trash/

https://www.palpa.fi/beverage-container-recycling/deposit-refund-system/

https://www.infofinland.fi/en/living-in-finland/housing/waste-management-and-recycling

https://www.lt.fi/en/media/bulletins/finland-cutting-edge-of-modern-plastic-recycling

https://earth911.com/business-policy/recycling-plastic-bottles-myths/

https://yle.fi/aihe/artikkeli/2019/05/02/kirkas-muovipullo-voi-kiertaa-ikuisesti-varilliset-pullot-eivat-kierra-samalla

https://www.hartwall.fi/vastuullisuus/nain-pullojen-muovi-kiertaa/

https://uusiomuovi.fi/pakkaus-kiertaa/uusiomuovista-on-moneksi/pramia-plastic/

https://www.tekniikkatalous.fi/uutiset/muovipullo-kiertaa-nyt-materiaalina/e35ec694-57ea-3921-847e-04eb7009cefa

https://www.talouselama.fi/uutiset/kertapullo-kiertaa-raaka-aineeksi/10d28298-e466-3478-acc8-c8685c83aea5

https://www.infofinland.fi/en/housing/waste-and-recycling

https://www.sitra.fi/en/cases/deposit-based-recycling-system-drinks-packaging/

The use of public telephones was common at the time and phone cards were seen as the cutting edge of development. Those were first launched on a large scale in 1986 in Germany by Deutsche Bundespost after three years of testing, and in France by France Télécom. Many other countries followed suit, including Ireland in 1990 and the UK circa 1994–1995. Tele (nowadays known with name Sonera) was the first to use phone card machines in Finland. Tele and several local telephone companies switched coin-operated telephones in telephone booths to card-operated telephone models in the early 1990s.

The cards had a certain amount of balance loaded at the time of purchase using chip technology. The first phase technology was technically quite simple and not very secure. But by the mid-to-late 1990s, highly secure technology aided the spread of chip phonecards worldwide.

The whole phone card technology was somewhat short-lived (especially in Finland) because in the late in the 1990′s they became unnecessary as cell phones became more common (thank’s to Nokia), which led to situation that the the previously common telephone booths disappeared from the street scene. Here are pictures of one 30 years old not so smart telephone booth calling cards used in Finland.

This type of telephone cards are the simplest type of “smart card”. The cards had a certain amount of balance loaded at the time of purchase, and this amount was stored to the card. Those telephone cards (as used in Finland and France) were technically simple memory card with smart card connector. This kind of memory cards only have some amount of memory inside the card and this memory can be normally read and written. There is normally nothing really intelligent inside those cards. There is a memory chip that has a small amount of card information it followed by memory are that contains the information of balance in the card.

A stored-value phone card stores the available balance in digital memory physically embedded in the card. This balance can be read by a public payphone when the card is inserted into the card reader. The stored-value system used in Finland write data to an embedded chip to reflect the new balance after a call. Used primarily for payphones, stored-value systems avoid the time lag and expense of communication with a central database, which would have been technically complex before the 1990s. In Finland the card had a memory area, where there was one memory bit for each token (30 mk card had 30 tokens) value in card. The tokens could be freely read, and one by one written to “used” state after use (but could not be turned back to not used state).

The technology worked, but it was not the most secure as a href=”https://en.wikipedia.org/wiki/Telephone_card”>the initial microchips were easy to hack. Some users found out that some cards could be hacked by scratching off the programming-voltage contact on the card, which rendered the phone unable to reduce the card’s value after a call. Also some people have built their own cards that looked like phone card to the phone, but they did not decrease the stored amount during use or were automatically reset back to card balance full state when removed from card. This kind of hack cards could be built at the time using a small thin circuit board and a small micro-controller soldered to it running a small program that emulates phone card operation.

I was interested in how those cards worked in the early 1990′s. I looked the technical information related to them and built my own hardware+software that allowed my PC to communicate with them.

Hacker magazine PHRACK issue 48 (September 1, 1996) published a two part article on electronic telephone cards technology. That article also mentions some of my work on the field (I improved some of the card communications software published in the article). The software enables you to dumb the memory of electronics phonecards to see the information in them. The software also allowed to write to cards (write out some bits to lower the balance).

You can find the article parts here:
Electronic Telephone Cards: How to make your own! (part 1)
Electronic Telephone Cards: How to make your own! (part 2)

Here are some picks from those articles:

{*****************************************************************************}
{ T E L E C A R D . PAS }
{*****************************************************************************}
{ This program enable you to dumb the memory of electronics phonecards }
{ from all over the world, so that you will be able to see which country }
{ the card is from how many units are left and so on …. }
{*****************************************************************************}
{ }
{ Written by Stephane BAUSSON (1993) }
{ }
{ Email: sbausson@ensem.u-nancy.fr }
{ }
{ Snail Mail Address: 4, Rue de Grand }
{ F-88630 CHERMISEY }
{ France }
{ }
{*****************************************************************************}
{* Thanks to: Tomi Engdahl (Tomi.Engdahl@hut.fi) *}
{*****************************************************************************}

After the information was more widely on-line, more and more people figured out how to hack those phone card to get free calls. People hacked those card and sold fake cards in Finland to the point that phone companies had to start to try to catch the users of fake phone cards and magazines started to write about the problem.

Here is one article from 1996 on the phone card hacking problems in Finland:
Puhelinkorttien jäljitelmillä huijattu ilmaisia puheluita Tele joutui korjaamaan tuhansien yleisöpuhelimien suojausta
” Poliisi tutkii Suomessa ensi kertaa paljastuneita puhelinhuijauksia, joissa on puhelinkorttien jäljitelmien avulla huijattu ilmaista soittoaikaa. Simulaatiokorteiksi kutsuttujen jäljitelmien avulla huijari on voinut soittaa ilmaiseksi kuinka kauan tahansa.”

Just few years later the system started to shut down because in addition to free calls problems the increasing owning of of mobile phones started to make phone booths not as profitable anymore as it once was.

Sources:
https://en.wikipedia.org/wiki/Telephone_card
https://www.epanorama.net/links/smartcards.html#memorycard
https://www.turku.fi/blogit/kukkuu-kokoelmista/kokoelmanosto-kuvat-kortilla-yleisopuhelimien-lahihistoriaa
Electronic Telephone Cards: How to make your own! (part 1)
Electronic Telephone Cards: How to make your own! (part 2)
https://groups.google.com/g/sfnet.harrastus.elektroniikka/c/k2yqfJVb_aA/m/fqmm4nNa4MwJ
https://www.hs.fi/kotimaa/art-2000003536142.html
https://www.antikvariaatti.net/kerailyesineet/puhelinkortit

Saunas are an integral part of the way of life in Finland. Sauna tradition is one of the most important parts of Finnish identity and cultural heritage. Finnish sauna culture is wet, steamy, sometimes smokey, an important part of the national identity. Most Finns cannot imagine not having a Sauna in their home. It’s estimated that there are about three million saunas in Finland – in other words, a sauna for every other Finn! In the basement of almost every apartment building there is a sauna. Typical saunas are continuously-heated wooden saunas in summer cottages and electric saunas in city apartments.

Sauna is good for everyone, young and old.For us Finns sitting in a 100-degree sauna is everyday business, but for a novice it’s an exciting (and highly recommended!) experience. Sauna culture in Finland is an integral part of the lives of the majority of the Finnish population. Sauna culture, which can take place in homes or public places, involves much more than simply washing oneself. In a sauna, people cleanse their bodies and minds and embrace a sense of inner peace. People threw water on hot rocks in a small room to create a hot and cleansing steam that was used to clean every pore of ones body. In your private sauna you can enjoy silence and relax by lounging on the benches. Public saunas, on the other hand, are social places where you should be prepared to chat with strangers.

Taking a sauna begins with having a wash (usually a shower), followed by a sit in the sauna room, the room being typically warmed to 80–110 °C (176–230 °F). Traditionally the Finnish sauna is taken without clothes, but this depends entirely on the place and your company. Water is thrown on the hot stones topping the kiuas, a special stove used to warm up the sauna. This produces great amounts of wet steam, known as löyly, increasing the moisture and the apparent temperature within the sauna. The humidity level is in Finnish sauna is most of the time often relatively low, typically up to 30% maximum. The normal temperature of the sauna is 70-90 degrees. A 100-degree sauna is also common, but for many it’s already too hot. 120 degrees is sheer macho. You should sit in the sauna for a short period at a time. A suitable duration is 10 minutes in sauna and 10 minute cooling after it.

Traditionally in old times and in rural areas the sauna is heated by burning wood. The wood stove sauna is very common type, and there is also savusauna (smoke sauna) does not have a chimney. Burning wood heats a large volume of sauna stones, onto which water is poured. The sauna stones are typically heated to around 200-400°C temperature.

Modern apartments have electric saunas. The most popular heaters for Finnish saunas are electric: they warm up the stones that radiate the heat inside the sauna. In city apartments, and in most public saunas, an electric sauna stove (sähkökiuas) is used, as it does not require open fire and offers additional features like time delay settings, thermostat and temperature limiter. Also electric saunas usually do have kiuas stones piled over or around the heating element to allow löyly thrown onto them. An electric sauna heater uses electricity to heat elements that create the heat that is characteristic of a sauna. As with wood burning sauna heaters, electric sauna heaters heat a large volume of Finnish olivine diabase sauna stones, onto which water is poured. This creates the distinctive löyly (pronounced ‘low-lou’, meaning sauna steam or sauna atmosphere) of an authentic Finnish sauna experience. Can you pour water on electric sauna? It is not necessary but highly recommended. Water should be thrown on the sauna heater rocks with the use of a ladle so that the right amount of water is applied. Once the water hits the rocks, it turns to steam. You should not pour too much water onto the heater though. The sauna stones are typically heated to around 200-400°C temperature and the electric heaters inside have much higher temperature (up to 580-680 °C).

There are very many saunas, and sometimes accidents happen. The sauna burns almost every day in Finland. Fires break out in sauna facilities in Finland about 400 times a year. Fortunately, sauna fires rarely lead to deaths. Typically users make mistakes lead to sauna fires – the wick gets misplaced on the heater, the clothesline fails, the heater is attached incorrectly. For safety reasons you should not dry your clothes in sauna or use it as a storage room, but some people do that. About two-thirds of sauna fires start in electric saunas. It seems that electric stoves are more prone to faults than wood stoves.

I have an electrically heated sauna at home and seen them fail. In the beginning of this month my electrical sauna stove had failure with flames coming out of it two days ago. Fortunately there was not major damage or anyone injured. When the flames started going out from the kiuas. First I switched off power from mains panel breakers (3x16A 400V) and then poured bucket of water on it to stop flames. Then I evacuated before the potentially very dangerous smoke get out from sauna, and closed all doors. My right initial moves worked to put fire before fire department arrived. Fire department then checked the situation and made sure that the fire had not spread anywhere (they used thermal camera to check the wooden sauna panels and kiuas).

This potential disaster got noted by Finnish National news organization because there has been some deadly sauna fires lately on news:

Onnettomuudet
Sähkökiuas syttyi palamaan Espoossa
Asukkaat saivat palon sammumaan kytkemällä sulakkeen pois.
https://yle.fi/a/74-20058225

According to the Länsi-Uusimaa situation center, the fire stayed in the stove itself and did not spread further. Flames were visible in the stove. There were no personal injuries from the situation.
The residents extinguished the fire in the electric stove by turning off the fuse. The rescue service suspects a short circuit as the cause of the fire.
The person on duty at the emergency center felt that the residents had acted well in the situation. If a fire breaks out in the electric stove, it is recommended to turn off the electricity, for example by removing the fuse from the electrical cabinet.
The situation center also advises to call the emergency number 112.
The rescue service of Länsi-Uusimaa also reported on the fire in the message service X.

The kiuas was made by a well known Finnish manufacturer Harvia. The company founded by Tapani Harvia in 1950 has grown from a small artist’s forge into one of the world’s leading sauna heater manufacturers and a forerunner in the sauna business. Harvia has remained a Finnish family enterprise and the Harvia companies now employ 250 people.

The kiuas was Harvia Vega, which is a popular type used in Finland (A total of 300 000 Vega stoves have been sold by 2017, of which approximately 180 000 in Finland, and the model is still sold). The exact model was Harvia Vega BC80, which is 8 kW heater powered from three phase power (3x16A 230/400V). Over the years there has been reports on problems with fire on the timer switch and in the heating elements.

Sähkökiukaista satoja vaaratilanteita – yleensä syynä rikkoutunut vastus article at
https://www.taloustaito.fi/koti/sahkokiukaista-satoja-vaaratilanteita–yleensa-syyna-rikkoutunut-vastus/#5b6c2129
says:

A loud bang is heard when heating the sauna. In the middle of the sauna, the heater starts to crackle and suddenly flames appear. When you throw the slather, the heater starts to roar and throw sparks. An unexpectedly broken electric stove can cause a fire or fire hazard. To prevent the fire from spreading in an emergency, it is important that there is nothing flammable near the stove.
According to the findings of the insurance company Lähi-Tapiola, the most common accidents caused by electric stoves are related to resistors breaking. The electric resistance is the part of the heater that creates heat in the sauna: it heats up and heats the surrounding stones.
“A heater is a device that wears out in use. The metal of the resistors can weaken and suffer, for example, if the heater stones do not cover the resistors and cold water is thrown directly on them. In addition, if the stones are allowed to move or crumble, they can twist and break the resistors,” from the Itä-Uudenmaa rescue service leading fire inspector Timo Kouki says in the press release.

Here is what the kiuas looks like:

A closer look shows the failed heater resistors:

The rocks are touching the sides of the heating element but not not sitting on top of those elements. The top stores have been moved during the incident and after it in inspection done by several people (fire department, me, electrician). It is interesting that I saw the fire from the heating resistors. They were coming from heating resistors because there was nothing else that could be flammable on the kiuas. Looks like the heating elements experienced a meltdown. Manufacturing defect?

The heating resistors catching fire is said to be quite rare, but it does happen sometimes. In addition to my case I know one other same model kiuas had had same thing happen. And I have witnessed many years ago this happen in a bigger kiuas (with flames, smoke and sparks) – you pour water on broken open heating element, of course sparks will fly.

To get the idea of the operation of electric kiukas, here are some views to the manual:

Here are the kiuas controls with the heat setting and timer:

Here is the picture of the different ways this kiuas can be wired to the electrical power supply. In my case the kiuas was powered from three phase 16A 230/400V 50 Hz mains power source. One interesting thing is that the kiuas does not use ground fault detector in the mains panel for protection, even if it is a device in environment where people throw water on it. The manual discourages the use of ground fault detector on the line powering the kiuas (due possibility of false tripping). Some people find electric sauna heaters frightening, first because RCD-s are not used with them and secondly because electrical connections underneath those heaters are really simple push-on connectors and open to moisture.

Sources:
https://featuringfinland.com/finland-sauna-culture-guide/
https://en.wikipedia.org/wiki/Finnish_sauna
https://ich.unesco.org/en/RL/sauna-culture-in-finland-01596
https://saunologia.fi/saunastandardit/
https://finnmarksauna.com/collections/electric-sauna-heaters
https://teplodar.eu/gb/14-heating-for-sauna?gclid=Cj0KCQiAr8eqBhD3ARIsAIe-buOC4wSFY2ao2C_ObbE7dDMv-iqZZndbuYxA3ZUevBiM5TNO3M3BqXgaAmhoEALw_wcB
https://www.fluidra.com/projects/finnish-saunas/
https://nordicperspective.com/culture/finnish-vs-swedish-sauna
https://www.harvia.com/fi/ideat-ja-trendit/vastuullisuus/vaihda-kiuaskivet-ja-vauhdita-saunan-lampenemista-saasta-energiaa-ja-aikaa/
https://taigatimes.com/blog/finnish-sauna-culture/
https://yle.fi/a/3-9917586
https://www.lahitapiola.fi/tietoa-lahitapiolasta/uutishuone/uutiset-ja-tiedotteet/uutiset/uutinen/1509582584409
https://yle.fi/a/3-9917586
https://www.finlandphilosophy.com/en-ww/harvia.aspx#:~:text=The%20company%20founded%20by%20Tapani,companies%20now%20employ%20250%20people
Sähkökiuas voi aiheuttaa palovaaran – ”Tärkeää, ettei ympärillä ole mitään syttyvää”
https://www.lahitapiola.fi/tietoa-lahitapiolasta/uutishuone/uutiset-ja-tiedotteet/uutiset/uutinen/1509576002863
Tutkimus: alkusammutus tuottaa tuloksia – hätiköinti aiheuttaa kuitenkin tarpeettomia vahinkoja
https://www.lahitapiola.fi/tietoa-lahitapiolasta/uutishuone/uutiset-ja-tiedotteet/uutiset/uutinen/1509582584409
https://keskustelu.suomi24.fi/t/11268125/harvia-vega—huippuluokan-peruskiuas
https://www.harvia.com/fi/tuotteet/HCB600400S/vega-bc60-60-kw-steel

Here are published material from the event:

https://www.uusiteknologia.fi/2023/11/07/teknologia23-messut-aukesivat/
- I took picture

https://www.uusiteknologia.fi/2023/11/08/teknologia23-suomessa-osataan-sirusuunnittelu-ja-piirituotanto/
- text and pictures

https://www.uusiteknologia.fi/2023/11/08/suomalainen-iot-yritys-voitti-tietoturvapalkinnon/
- picture and text material

https://www.uusiteknologia.fi/2023/11/10/teknologia23-tarjosi-passiivijaahdytysta-reunalaskentaan/
- text and pictures

More articles on event:

https://www.uusiteknologia.fi/2023/11/09/biosignaalien-mittaaja-voitti-startup-kisan/

https://www.uusiteknologia.fi/2023/11/09/tietoturvan-cyber-security-nordic-kiinnosti/

Neural DSP is developing technology to advance the state of the art in the music industry – mainly effect plug-ins and DSP software and Quad Cortex DSP guitar effect box. Darkglass Electronics concentrates on making effect box hardware. Neural DSP has fast become a household name on the new frontier of amp modelling and guitar effects.

Neural DSP Quad Cortex is a pro-quality amp modeller and effects unit that presents its many features in an easy-to-use format. The Quad Cortex, is a floor-based unit that presses all that next-gen algorithmic sorcery into service in an anodised aluminium unibody. The Quad Cortex features a bright seven-inch LED touch-screen that allows you to adjust parameters and arrange signal chain. User can adjust the sounds and access all the functions from the touch-screen and the stomp+rotary actuators.

The Quad Cortex derives 2GHz of DSP power from SHARC+ processors that gives it its name, and this puts a lot of sounds on the menu. Quad Cortex may be the most powerful floor modeler on the planet with a total of 6 cores (4x SHARC+ and 2x ARM Cortex-A5 running at 500MHz each).

Here are some pictures I took at Knotfest Finland 2022 festival on the guitar effect setup Slipknot uses (from Slipknot museum featuring Fender Jim Root Jazzmaster):

Here is one video I found from YouTube related to Slipknot and Neural DSP Quad Cortex:

SlipKnoT – Surfacing | Bass Cover | Neural DSP Quad Cortex test

Sources and links to more information:
https://neuraldsp.com/
https://www.darkglass.com/
https://neuraldsp.com/plugins
https://neuraldsp.com/quad-cortex
https://www.musicradar.com/reviews/neural-dsp-quad-cortex
https://soundtools.fi/verkkokauppa/neural-dsp-quad-cortex-efektiprosessori-ja-vahvistin/
https://www.reddit.com/r/Guitar/comments/s5a2a2/play_tried_the_neural_dsp_archetype_petrucci/
https://kaaoszine.fi/mika-yhdistaa-foo-fightersia-slipknotia-ja-wintersunia-suomalaiset-darkglass-electronics-ja-neural-dsp-vievat-huippumodernia-soitintekniikkaa-maailmalle/