Heat pumps: Why New York wants to hang them in the window
Hardly any major American city is without air conditioning. In New York City, simple window models are now to be upgraded to heaters.
Classic window air conditioning (aka heat pump) in Manhattan: surely that must work better?
(Image: Ben Schwan)
New York City is known for being uncomfortably hot in summer. It can reach 33 degrees or more, and there is also often high humidity from the sea, which hits people like a wall. So it's no wonder that most apartments have heat pump-based air conditioning. But in their current form, these are neither particularly energy-efficient nor can they heat. New systems, which the city and state now want to implement with a funding program, could provide a remedy and also serve as a model for other countries.
Iconic boxes
There are several types of air conditioning systems in New York City. The classic, almost iconic version is a device that is simply placed on the windowsill in any room that needs to be cool: As the standard windows in New York apartments are usually pushed upwards, this is the obvious choice. Insulation material is then placed to the left and right of the large box.
The operating principle: cold air is blown into the room as part of the heat pump principle, hot air is released into the environment without hoses in the hope that it will not be sucked back into the room, which is rarely the case thanks to the powerful British Thermal Unit (BTU).
In more modern buildings, there are two alternative A/Cs: Firstly, there is "Central Air", i.e. a centrally controlled air conditioning system for the whole house, which can be recognized by the air outlets in the apartment and a central control system. This system often also controls the heating. Secondly, there are split air conditioning systems, which are also becoming increasingly popular in Germany, where the air outlet unit is located in the room. The rest of the hardware, including the actual heat pump, is connected via a pipe through the room and is then located in the outside window area, on the balcony or on the roof. Split air conditioning systems could actually also heat, but are rarely used for this purpose in New York. Instead, there are still many ordinary radiators with oil or gas firing.
More and more heat waves
Standard A/C based on the window sill principle results in high electricity consumption and places a heavy load on the grids in midsummer. In the past, this has led to rotating power cuts at traditional switch-on times. Thanks to climate change, this could increase in the future, as it is unlikely to get any cooler, which will increase the use of air conditioning.
By 2080, it is expected that there will be up to six times more days with temperatures above 32 degrees in New York City – the number of heatwaves per year is even expected to increase fivefold. Around 350 people already die every year as a result. Persuading New Yorkers to leave their air conditioning switched off and perhaps use more energy-efficient fans is therefore pure wishful thinking: If A/C is available, it will be used; for many, it is considered something of a human right given the summer heat along with the aforementioned high humidity.
