French startup Equium has developed a heat pump core that works on acoustic waves and produces hot and cold air. Equium manufactures the core and works with another company that integrates it into heat pump systems. The units are scalable from 1 kW to 3 kW and are designed for residential applications.
The novel heat pump can purportedly reach higher temperatures than existing heat pumps, without the need for refrigerants. It works with a high-fidelity (Hi-Fi) speaker powered by electricity that creates an acoustic wave in a closed-pressure vessel filled with helium at a pressure of 30 bars. The acoustic wave causes the gas to compress or expand, displacing heat from a lower temperature to a higher temperature, or vice versa. The heat pump core is filled with water, which absorbs or releases that heat.
“The acoustic wave does the work of compression and expansion of the gas that produces heat or cold, respectively,” Philippe Loyer, a product manager at Equium, told pv magazine.
Loyer said the heat pump can generate domestic water at up to 80 C. He claims that one of the key benefits of the acoustic heat pump, in comparison with traditional units using refrigerants, is its ability to reach very high or low temperatures.
“Traditional heat pumps use refrigerants with a temperature phase. They a have temperature limit, which is the temperature of the changing phase from liquid to gas of the refrigerant,” said Loyer. “In our core, the helium stays in gas form. Because helium remains a gas until -200 C, we can achieve higher temperatures inside our heat pump core.”
The heat pump purportedly works with all external heat sources, including air sources from -15 C to 50 C. Given that its core is filled with water, it works best as a water-source and geothermal heat pump. To be used as an air-source heat pump, the unit can be equipped with a fan that transfers the heat from the air to the water, according to Loyer.
The heat pump has a coefficient of performance (COP) of three to four, which means that it produces 3 kW to 4 kW of heat for each kilowatt of power it consumes. Equium is targeting 8 kW to 10 kW of thermal power for its heat pump core, Loyer said. It has a 30-year lifetime, with an easy installation process. The acoustic heat pump also offers better modulation than traditional units.
“We have the same efficiency as traditional heat pumps, but we have better modulation thanks to acoustic transfer,” said Loyer.
Traditional fixed-output units cycle between on and off multiple times a day, switching between zero and maximum capacity to achieve the right temperature balance. But the new heat pump modulates its output to continuously provide the desired temperature.
“The output regulation of a classical heat pump is very energy consuming. On our acoustic system, the regulation is very easy,” Loyer explained. “If you want less power, you can just decrease the volume of the Hi-Fi speaker.”
Equium claims that the heat pump system is completely silent, despite the use of a speaker to generate the acoustic wave. The level of noise is reportedly lower than 30 dB – the equivalent of a whisper.
“The sound our system produces stays confined inside the core, so you cannot hear it from outside,” said Loyer.
Equium is now conducting field tests for its thermos-acoustic heat pump. It expects to launch it at the end of 2023.
*This article was amended on 03/01/2023 to reflect that the helium is at a pressure of 30 bars and that it remains a gas until -200 C, not -300 C as previously reported.
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How can it produce more heat than the energy it uses? That breaks one of the laws of thermodynamics.
Strictly speaking, the heat pumps uses 1 kW of electricity to move, not produce, 3 kW to 4 kW of heat. Of course, that extra heat is being moved from the external source, and not being created from nothing. Heat pumps don’t just convert work to heat, they pump additional heat from a heat source, which is why their COP can be higher than 1. Thanks for bringing this up.
“Because helium remains a gas until -300 C, we can achieve higher temperatures inside our heat pump core.”
I thought it was impossible to be colder than -273,15 C. Is it an error in the article or have I missed something?
You’re correct, it was meant -200 C. The article has been amended, thank you.
Hi-Fi stands for High Fidelity! Like in music! It doesn’t make any sense with heat pump!
All heat pumps offer a 3 to 4 multiple in theory, few ever achieve it. Lifespan of 39 years would be amazing but most likely is another fib.
I had a traditional heat pump for more than 25 years never had a problem. It was still going strong when I sold my home.
Inverter heatpumps are the norm and have been for well over a decade. These do not cycle on and off as stated in this article but regulate the refrigerant pump and fan to maintain room temperature. The main advantage of this new system is no ozone atmosphere damaging gases as used in traditional heatpumps
Can this unit potentially be used as a chiller for a residential water cooled air conditioning unit?
The use of Helium seems expensive. Are there alternatives?
Helium is not a consumable here, so one time fixed cost should be minimal.
“The heat pump purportedly works with all external heat sources, including air sources from -15 C to 50 C.”
What happens when the heat sources temp drops below the -15C ?
Do you even have any idea how much helium costs, we have been doing things all wrong let them get it right for a change and no helium is not that expensive
So when will people actually be able to buy them? Amd *without* taking out a second mortgage?
Maybe where you live. Where I live (California) compost is sent to an energy production facility.
How about a compost heat system? Wood chips today go to the landfill.
This invention is awesome as well.
So how does 1 energy kW input produce 3-4 kW heat energy output. Is this a new law of thermodynamics?
Strictly speaking, the heat pumps uses 1 kW of electricity to move, not produce, 3 kW to 4 kW of heat. Of course, that extra heat is being moved from the external source, and not being created from nothing. Heat pumps don’t just convert work to heat, they pump additional heat from a heat source, which is why their COP can be higher than 1. Thanks for bringing this up.
I thought the molecules of hydrogen and helium were so small that they eventually leak from the vessel they are captured in. But perhaps this issue has been solved. Something I read or heard long ago.
Denser metal should hold for decades
3/02/23?
I meant 3/01/2023, it’s been changed. Thanks!
What companies are they working with to integrate into the systems for use?
There is a typo on the date of the amendment it says it was amended on February third, or march second, 2023 when the date as of writing this comment is January third, 2023.
Thanks, it’s been changed to 03/01/2023 (3 January 2023).
50C is 122° F
It gets hotter than that here. Would it still work at 130° F?
Without the temperatures of the source and sink COP of 3 or 4 is meaningless.
The temperatures of the sources are:
Air: -15 C to 50 C
Underground water: around 10 C
Water circuit: 15 C to 45 C
Ground source: 10 C to 20 C
Not to put a damper on the parade, but Helium is difficult to contain. It’s small atomic size creates challenges to seal. Even metal containment has sub micron grain boundaries allowing He to diffuse over time. To last 30 years at 30 bars without the tank depressurizing will be an engineering balance of material construction, wall thickness, and quality of welded joints. And if not permanently sealed then any port to refill offers additional leak paths. Curious to know the sensitivity of pressure degradation to the acoustic heat pump performance.
“heat pump core that reportedly produces 3 kW to 4 kW of heat for every kilowatt of power it consumes”
What happened to the first law of thermodynamics?
Strictly speaking, the heat pumps uses 1 kW of electricity to move, not produce, 3 kW to 4 kW of heat. Of course, that extra heat is being moved from the external source, and not being created from nothing. Heat pumps don’t just convert work to heat, they pump additional heat from a heat source, which is why their COP can be higher than 1. Thanks for bringing this up.
More than happy to comment and support this appointment for Helium application to this process.
Can this system be use as an air conditioner for cooling homes ? ( versus compressor air conditioners )
Hi
Have you got a test bed for a domestic application ( in the UK per chance? ) using ground source connection.
Would like to see how the kit can be retro fitted to replace existing gas LPHW heating and hot water systems – either individual systems or augment / replace communal systems.
Hi,
I’d be interested in testing one out here in Maine USA. Looking to add a heat pump this coming year.
This technology could be the solution I’ve been looking for. I’m the owner of an HVAC company located in Colorado and currently have a large clientele with compromised geothermal loops. Most of them are most likely fusion mistakes that lead to pinhole leaks and can be pressurized several times a year, but that is just a bandaid without solution. I’ve replaced multiple geo systems in locations where there is no fuel source and installed air source heat pumps. The problem is that the heat pump condensing units lose capacity at 30 Fahrenheit and switch to heat strip. I would like to know if the heat exchanger connections for this system are brass, copper, or aluminum, and if a reservoir feeder helium tank can be installed on the system. Also which type of charging port is used if there is no feeder.
Hopefully there is a thermostat for this unit with communicating capability and wireless outdoor sensor input.
If it’s true that the helium heat pump will be comparable in price to high end modulating heat pump condensing units, sign me up!