Heat pumps are home heating and cooling devices powered by electricity, not fossil fuels, making them a great way to fight climate change by switching to electric.
How Do Heat Pumps Work?
These indoor heating and cooling appliances use refrigerants to transfer heat and provide home comfort, hot and cold. If you’ve ever used a window air conditioner, you know they work by taking in air, running that air over coils cooled by refrigerant, then blowing the cold air out the front, and dumping the heat captured by the coils out the back. Thats a heat pump.
While window air conditioners were not designed to heat your house, you could do so by just putting one in your window backwards: heat in, cold out. Thats how heat pumps work. And heat pumps have one significant sustainability advantage over most current alternatives. Unlike furnaces, heat pumps are electric so they don’t burn fossil fuels! So powered by renewables, this makes them a viable, environmentally friendly option that fights climate change.
How Are Heat Pumps Flighting Climate Change?
While furnaces generate heat by burning fossils, heat pumps transfer heat from the outside. Heat pumps can run in two directions, which is a slight modification from how furnaces work. Heat pumps can provide heat in the winter and still cool down homes during summer.
Traditionally, low oil prices and a lack of climate awareness has meant most northern homes depend on fossils for heat. This burning of fossils has become one of the leading causes of greenhouse gas emissions globally. Heat pumps eliminate the need to burn fossils to generate heat.
Electric heat pumps have a compressor and a circulating structure. The pumps use these features to extract heat from outside sources by pumping the heat inside. The amount of electricity used during this process is minimal. During summer, the heat pump reverses this process. In both instances, there’s limited emission of greenhouse gases. The ability to achieve this duo function with negligible carbon emission underscores the emerging popularity around the use of heat pumps.
A Low-Carbon Alternative With 300% Efficiency
A heat pump generates around 4KW of thermal energy for each KW of electricity consumed. This represents about 300% of efficiency. How is that possible without violating the second law of thermodynamics? Remember, heat pumps don’t create heat, they transfer it from one source to another (e.g outside air to inside air). By way of analogy, a regular household fan doesn’t create the oxygen that comes out the front, it just moves it from the back to the front. In cases where heat pumps generate energy from renewable sources such as hydro and wind, the heat is 100% renewable.
Comparison with other heating technologies:
- Heat Pump: 300% efficiency
- Condensing gas/oil boiler: 90-96% efficiency
- Conventional gas/oil boiler: 70-80% efficiency
- Direct electric heating: 35-45% efficiency
Heat pumps further reduce the use of primary and final energy, that is the energy used to produce, transport and deal with the waste created when generating energy. The cost cut through reduction could be helpful in further combatting climate change.
The Main Types of Heat Pumps
The extent of environmental friendliness in a heat pump differs depending on the different types. There’re three types of heat pumps. You could consider any of these options depending on your source.
· Air Source
These are the most commonly used types of heat pumps. They are inexpensive but highly effective. You may consider these pumps if you live in moderate climate regions. Outside air is the medium of exchange when using these heat pumps.
· Water Source
Though rare, water sources heat pumps dissipate heat through water and not air. These pumps require a lake or other water sources to work. The City of Toronto’s Deep Lake Water Cooling (DLWC) system is an example.
· Ground Source Heat Pumps
Ground source heat pumps offer much more efficient operations but are also much more expensive to install. These pumps take advantage of thermal energy transferred by the sun into the ground. Long pipes are run underground where the temperature is stable year round. In the summer, heat is pumped into the ground. In the winter, heat is pumped out.
A Lasting Solution to Climate Change
Heat pumps are a great solution to this emerging threat of climate change. When paired with renewable energy sources like solar or wind, they can provided 100% renewable, decentralised energy. But even when tied to fossil fuel powered grids, heat pumps’ efficiency minimise greenhouse gas emissions significantly. Heat pumps could present an important paradigm shift in managing the impact of climate change.
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