#18 Air-Source Heat Pumps
#18 Air-Source Heat Pumps
Moving air heat to stay warm or cool
Read time: 3 minutes
In this week’s issue you will learn about a great way to save energy and money when heating and cooling your home: Air-Source Heat Pumps
“Without action to address energy efficiency, energy demand for space cooling will more than triple by 2050” - International Energy Agency
Top Air-Source Heat Pump News 🗞️
Performance in cold weather: A recent study has debunked the myth that air-source heat pumps don’t work in cold weather conditions and that they are inefficient to run.
Sales through the roof: In regions all around the world, like the UK, Spain or the US, air-source heat pump sales have surpassed those of gas furnaces.
Let’s dive in 🧠
Some crazy stats to start:
50% to 70% of all energy used in homes goes towards heating and cooling.
15% of global carbon emissions comes from heating and cooling buildings.
Cooling is the fastest growing use of energy in buildings.
Hopefully, this shows why it’s so important to figure out how to decarbonize Heating, Ventilation and Air Conditioning (HVAC) in buildings.
One potential solution are geothermal heat pumps, which I already covered here.
Today I’ll focus on air-source heat pumps.
What are they and why are they so awesome?
It’s a clean HVAC alternative that captures the heat from the ambient air and takes it out to keep your house cool or brings it in to keep it warm.
It’s becoming extremely popular because:
In about 4 years you can get your money’s worth.
They can be combined with solar PV to make the system even more sustainable. This is the best combo.
They have a Coefficient Of Performance (COP) between 3 and 4. That means by providing 1 kW of electricity you can get up to 4kW of heat energy for your house. They help save a lot of money compared to other HVAC systems.
How do they work?
In the air there is always some heat. Even if it’s really cold, there’s always some heat in the air.
The heat pump extracts that heat from the air and moves it into the house or outside of it.
Ideally this whole process is powered by renewable energy to make it even more sustainable.
In the winter:
The little heat in the cold air is captured by a refrigerant liquid present in the heat pump.
The refrigerant warms up and turns into a gas that is then compressed and thus heated even more.
That heat from the refrigerant gas is passed on to the water (air-water heat pump) in your house or to the air (air-air heat pump).
In the summer:
The process is reversed. The hot air from the house is transferred outside through the refrigerant.
The colder it is outside the harder it will be to capture the heat from the air and thus the more electricity will be consumed to power the process.
Air-source heat pumps went from being unknown to now having some huge momentum.
I really suggest you consider this as an alternative to AC and other HVAC options for your house.
Cons
Upfront cost: They are quite expensive to install and on top of that you need to add the installation of the heat dispersion method (radiators, radiating floors, etc.).
Locations: It might not be the best option in places with extremely low temperatures (below -10ºC). It still works but in a less efficient way since lots of electricity is needed to make the system work.
Aesthetics: The fan placed on the outside can be noisy and look bad on the facade of a building.
Top Air-Source Heat Pump Companies 💰
Most of the big appliances companies like Haier or Mitsubishi make them. Here are three startups doing things differently:
Aira: They are 100% vertically integrated and thus can create the perfect direct-to-consumer experience. Oh, and instead of spending 20k, you get their heat pumps on a subscription model where you pay just a little every month!
Qpinch: From Belgium. They turn wasted heat into useful industrial process heat, helping companies lower their bills and their carbon footprint.
Equium: From France. Their thermoacoustic heat pumps use very powerful sound waves to produce both heat and cold.
❗Extreme knowledge area❗
Heat pumps video: A more visual and detailed explanation of how air-source heat pumps work and the math behind the installation.
Types of heat pumps: A guide from the US Department of Energy to help you choose among the different types of air-source heat pumps.
The future of cooling: A report from the International Energy Agency showing the current and future state of the cooling demand and possible solutions.
That’s it for today, 1 climate tech topic in under 5 minutes.
Next week… Bioplastics! 🤯
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