7 reasons why a heat pump is like an Atlantic bluefin tuna
A heat pump is like a fridge in reverse: a fridge cools and emits heat at the back, while a heat pump heats and emits cool air. We have all heard of this analogy, and are probably getting a little tired of it. So what else could a heat pump be compared to?
The answer is the Atlantic bluefin tuna. Here are 7 reasons why the bluefin would make the perfect mascot for a heat pump company.
1) Heat exchange
The Atlantic bluefin tuna has the ability to regulate its body temperature using a mechanism called countercurrent exchange. Taking in oxygen from the cold ocean water over its gills cools the bluefin’s blood, while swimming and hunting warms it up. To capture the heat, the bluefin has developed a nifty network of blood vessels: cold and oxygen-rich blood on the way to the swimming muscles passes by the warm blood on its way out, so the heat jumps over to the cold blood instead of being lost into the ocean. This makes the bluefin tuna one of the few warm-blooded fishes.
This mechanism reminds us of a heat pump. A heat pump makes use of existing heat, for example from the surrounding air or a water source, just like the bluefin tuna uses its warmed-up blood. The heat pump concentrates that heat and uses it to heat water, which is then directed to radiators and underfloor heating to warm your house, just like bluefin tuna with its network of blood vessels.
No need to burn any fossil fuels: all you need to keep your house and fish warm is a clever way to capture and redirect the heat you’ve already got.
2) Efficiency
Being able to stay warm, even in cold water, is a huge advantage for the bluefin tuna. They can swim and process information much faster than their fellow hunters and prey, whose body temperature depends on their environment.
With their warm-bloodedness and streamlined design, they can reach a maximum speed of 40 miles per hour, outswimming Great White sharks and Orcas. Yes, preserving energy makes you the Number One!
Similarly, heat pumps do not burn any fossil fuel to generate heat, but only use electricity to transfer the heat. This makes them at least three times as efficient as gas boilers in the right conditions. For example, a COP (Coefficient of Performance) of 3 indicates that a heat pump supplies 3 times as much heat energy to the system as it consumes in electrical energy.
For now, Orcas and gas boilers may be more popular than bluefins and heat pumps, but when it comes to efficiency and recycling heat they are swimming far behind our real champions.
3) Size
The Atlantic bluefin tuna is much larger than you might expect: hatching at the size of a human eyelash, they can grow as large as a polar bear!
Fortunately, heat pumps aren’t quite that large but they do take up a bit of space in your garden or basement, so their size should not be underestimated. On the bright side: if you feel you could fit a polar bear in your backyard, you’ll definitely have enough room for a heat pump.
Tip: With this AR app from pump:chic, you can get a better feeling for how much space a heat pump would take up in your home.
4) Non-stop
A bluefin tuna can cross the Atlantic in a couple of months, but it needs a constant flow of water passing over its gills to absorb the necessary oxygen. This means that it has to be constantly on the move, without ever stopping.
The same is true for heat pumps. While a gas boiler can be switched on and off at any time, a heat pump is usually kept running without interruption. It cannot adjust the room temperature as quickly as cranking up your gas boiler would, but it will steadily warm up your house. Have patience, and “just keep swimming”.
5) They thrive everywhere
Whether hatched in the Gulf of Mexico or in the Mediterranean Sea, bluefin tuna populate the entire Atlantic ocean. Their hunting area reaches from Iceland, to Texas and Brazil, and over to Senegal and beyond. They feel comfortable everywhere, from tropical to subarctic waters.
Heat pumps are the same. While many believe that heat pumps won’t work in colder climates, they can still absorb heat in extremely low temperatures such as -20 °C. So the only ones that can legitimately use that excuse for not getting a heat pump are the polar bears…
And for those frying in hot weather, some heat pumps can also be reversed and used to cool their home.
Tip: Find out more about the distribution of heat pumps in the UK in this article featuring an interactive map.
6) Costs
The Atlantic bluefin tuna is considered a delicacy, especially when consumed as tuna sashimi. As the demand for bluefin tuna has drastically increased over the last few decades, an individual fish can sell for 10 000 USD or more.
Heat pumps cost about the same. According to MCS data, the installation of an air source heat pump ranges from around £8,500 for a flat to £12,500 or more for a large house, with the median cost being around £10,000. Fortunately, the Boiler Upgrade Scheme offers grants of £5,000 to reduce the installation costs for air source heat pumps.
Tip: You can use our cost estimator to get a rough estimate for your own house.
7) There aren’t enough…
Due to their popularity, the bluefin tuna has become a victim of overfishing and illegal fishing, rendering it the most endangered tuna species. They still have a chance to recover with further conservation efforts, but they need our help and protection to make it.
As with the bluefin population, there aren’t enough heat pumps around to keep our planet healthy in the long run. Homes are directly responsible for roughly 14% of UK emissions. While heat pumps are a great solution for low-carbon heating, there are currently only about 500 000 of them installed in UK homes. To reach NetZero by 2050, over 25 million boilers will need to be replaced by a low-carbon heating system like a heat pump.
We have to increase the numbers of both Atlantic bluefin tuna and heat pumps to save our planet. While we at Nesta know very little about protecting the bluefin tuna, you can learn more about heat pumps and how Nesta is working to reduce domestic carbon emissions on our website and by following our articles on All you can heat.
And next time you’re asked to explain how a heat pump works, drop the fridge analogy and tell them about the amazing Atlantic bluefin tuna instead.
—
Many thanks to the creators of this video for introducing me to the bluefin tuna and triggering the inspiration for this article.
