The love of one’s own home is unevenly distributed. If Green Anton Hofreiter is at one end of the scale, Christian Haschek is at the other end. The 33-year-old IT specialist knows every power cable in his house in Lower Austria. Now he has built a heater that makes money for him: a computer with four graphics cards that work so hard that they get 80 degrees. With the machine, Haschek produces the crypto currency Ether – a competitor of Bitcoin. Unlike money from a central bank, cryptocurrencies are calculated by computers. To create an ether, they have to crack math puzzles – they mine. This puts such a strain on the processors that they get very warm.

Haschek’s miner – an inconspicuous box full of cables and circuit boards – is in his garage. The waste heat from the machines heats the air, which in Lower Austria can drop to well below zero at night. “On cold days, I had electricity costs of six to eight euros a day, now only half,” he says.


That sounds crazy because the production of crypto currencies notoriously consumes a lot of electricity, after all, the computers have to rattle continuously. But the hype is huge, the prices are going through the roof, and Haschek’s old computer has become a heating money machine. A unit of ether is currently worth 1200 euros, Haschek’s “heating” incessantly produces fractions of it, ether cents as it were: “Although the cards cost three euros in electricity, I still get twelve euros out of it a day.”

Crypto heaters like Haschek have linked their electricity bills directly to a speculative boom. It is becoming increasingly clear that Ether and Bitcoin are less currencies in the classic sense than pure bets. Consumer advocates are warning of a bubble that will end up with a few scorched computers instead of withered tulips.

Using the waste heat from computers for heating is an idea not only for cryptocurrency fanatics. In the former data center of the European Central Bank in Frankfurt, companies now let artificial intelligence learn tasks. The heat from the computer heats the hotel above.

christian haschek ether

“That could all end badly,” says Christian Haschek about his special heating.

(Photo: oh)

Haschek’s heating at the Leibniz Computing Center (LRZ) Garching, where the SuperMUC high-performance computer is located, is considered to be rather inefficient. Among other things, it simulates complex molecular structures for pharmaceuticals for scientists. In doing so, it produces an umpteen times more heat than Haschek’s garage construction. The Garching researchers also use the supercomputer to heat their offices. LRZ manager Dieter Kranzlmüller says he even has too much computer heat: “It is a challenge for us to find buyers for the rest.” And he explains: “Computers’ do not ‘consume’ electricity. They only convert electrical energy into thermal energy, and they do it very efficiently.” This is why Haschek’s construct is worthwhile at all – as long as electricity is cheap and the ether price is high.

So everything depends on the ether hysteria: “That could all end negatively,” says Haschek. “If the price drops too far, I’ll turn off the miner. Or if it gets too warm outside.”