Wed 1 Nov 2023

Why is a heat pump energy efficient?

Unless you’ve been avoiding the news or social media for the last few years, you will have heard that installing or upgrading your home’s heating to a heat pump system is an energy-efficient way to heat and/or cool your home. But what is it that makes a heat pump energy efficient?  


Firstly, it's important to define the types of heat pumps that we will be talking about in this article: 


There are air-to-air heat pumps, which generally consist of 1 outdoor unit that is connected to an indoor unit - wall-mounted, ducted system and consoles - that provide cooling and heating to indoor spaces. To visualize one, just think of the air conditioners you see mounted on the wall in homes and some offices.  


Then there are air-to-water heat pumps which transfer heat from the outside air to water that is then moved around the house using radiators or underfloor heating.  


Choosing between them depends on the climate and your heating/cooling needs, or even domestic hot water which air-to-water offers alongside heating and cooling. 


In this article, our focus is air-to-water heat pump systems and we're going to look at what makes a heat pump energy efficient. 


Are heat pumps a better option to lower your environmental impact? 


An energy efficient heat pump serves as a more environmentally friendly solution for indoor spaces since they help reduce your home’s impact on the world around us as they don’t require the burning of fossil fuels for heating. 


As mentioned above, air-to-air heat pumps utilize indoor units or ducts to distribute warm or cool air indoors. In contrast, air-to-water heat pumps transfer heat to a water-based central heating system, which then circulates heated water through radiators or underfloor heating and can provide domestic hot water. Additionally, heat pumps produce no harmful emissions locally during operation as they run on electricity. 


Do heat pumps reduce your carbon footprint? 


Put simply, yes. An ​​air-to-water heat pump's carbon footprint is significantly lower compared to traditional gas boilers. By installing this type of heat pump system, you can substantially reduce your carbon footprint. In fact, the installation of these systems has the potential to reduce carbon emissions by over 23 tons of CO2 within a decade, making them a better choice for environmentally conscious homeowners. 


Do heat pumps improve indoor air quality? 


It is important to note that while air-to-air heat pumps can contribute to​​ indoor air quality (IAQ) by utilizing filters, air-to-water heat pumps don't offer the same benefit since they don't use filters. The key distinction lies in the fact that air-to-air systems use indoor units that can have filters fitted, giving air-to-air systems the upper hand in improving indoor air quality. 


Air-to-air residential heat pumps, especially ductless ones, can have a positive impact on IAQ, which is particularly beneficial for individuals with allergies or breathing sensitivities. Ductless heat pumps are equipped with removable and washable filters that can be easily cleaned using a vacuum and tap water. This straightforward maintenance process helps reduce indoor pollutants and allergens building up in units and keeps the air coming out healthier for longer with minimal effort by the user. 


What makes a heat pump efficient for heating the home? 


Unlike traditional heating systems like gas boilers and furnaces, heat pumps don’t use fossil fuels for heating the home and only use electricity to keep it running. For example, within the range of Hitachi air-to-water heat pumps, you’ll find systems that provide ​​heating, cooling and domestic hot water that have an A+++ class energy rating.  


This technology is especially efficient during colder seasons when heat pumps extract warmth from the chilly outdoors to heat indoor spaces. For example, air-to-water heat pumps are capable of operating even in conditions as low as -25°C, making them suitable for colder climates.  


Air-to-air heat pumps, on the other hand, can be an efficient source of heat in climates where temperatures drop as low as -20°C. 



​​​Air-to-water heat pump vs. Boiler 

Heat pumps and boilers stand as prominent contenders for home heating systems, each functioning through distinct mechanisms. A boiler uses fuels like natural gas, propane, or heating oil to generate heat, distributing it through radiators or underfloor heating. Air-to-water heat pumps employ electricity to move heat through the home without the use of extra fuel to produce heat.  


While boilers are typically 90-95% efficient, heat pumps boast 300-400% efficiency due to their heat extraction process, meaning 3 to 4 times more heat per kilowatt. Heat pumps outshine boilers in terms of energy efficiency, reducing energy bills. The potential global impact is also significant, as a shift from traditional boilers to heat pumps helps reduce CO2 emissions. Moreover, heat pumps offer installation versatility, compactness, and a greener solution, making them a compelling alternative to boilers for both residential and commercial applications. 

Air-to-air and air-to-water vs. air conditioning 

When comparing air-to-air heat pumps, air-to-water heat pumps, and air conditioning systems, it's essential to understand their similarities and differences within the realm of HVAC solutions. Firstly, the main difference between an air conditioner and an air-to-air heat pump is that air conditioning units specialize in cooling, passing warm air over cold refrigerant to move heat from inside to outside, while heat pumps are versatile and capable of providing both cooling and heating


Air-to-water heat pumps, as mentioned above, are most similar to a traditional boiler system, using radiators and underfloor piping to provide a home with heating and cooling. 

Most efficient heat pumps 

Within the range of Hitachi air-to-water heat pumps, you’ll find the ​​range Yutaki. The air-to-water heat pumps, including regular and high-temperature models, offer versatile options for various property types. These units operate even in harsh winters, delivering hot water at up to 52°C in temperatures as low as -25°C. These solutions feature compact designs that can fit within a standard kitchen cupboard and offer easy installation and maintenance access with simplified pipe layouts. 


For homes without existing pipework, Hitachi's fan coil units provide an effective space heating and cooling alternative. These deliver the needed temperature to spaces by blowing air over water pipes.  


With quick water heating times and remote management capabilities, Hitachi's Yutaki heat pumps prioritize both comfort and energy, becoming one of the most efficient heat pumps on the market. 


Air source heat pump building regulations 

When installing an air source heat pump, it is essential to ensure that both the building work and the heat pump appliance adhere to the applicable building regulations. Before considering the installation of an air source heat pump in your home, it's crucial to thoroughly research and understand both local and national building regulations. These regulations vary from region to region and country to country, encompassing aspects such as permits, zoning, noise limits, safety codes, and environmental standards. Ensuring compliance with these regulations is not only to avoid legal issues but also to ensure the safety, efficiency, and effectiveness of the heat pump system. By doing so, homeowners can make informed decisions, avoid potential setbacks, and ensure a successful and hassle-free integration of the air source heat pump into their property. 


Two workers looking at the laptop searching in a construction site

Subsidies and grants for sustainability 

Subsidies and grants not only help reduce the financial impact of installation but also play a role in generating awareness of residential energy efficient heat pumps and their adoption around the world. As the initial investment costs for eco-friendly heating and cooling systems like heat pumps can still be higher compared to conventional fossil fuel dependence alternatives, financial support programs are necessary. These incentives encompass various forms, such as low-interest loans, grants, and tax rebates, tailored to different income brackets. 


For example, the EU's legislative initiatives, including the Renewable Energy Directive, Energy Efficiency Directive, and Energy Performance of Buildings Directive, have urged Member States to establish such subsidy schemes. The recent REPowerEU plan underscores the importance of accelerating green technologies, emphasizing the rapid deployment of heat pumps, integrating renewable energy sources, and transitioning from fossil fuel to heat pump subsidies. These initiatives aim to drive the transition towards cleaner heating solutions while fostering skills, research, and development, and making sustainable heating financially attractive. 

Is a heat pump right for you?  


Depending on your heating and cooling requirements, and the type of building you live in, air-to-air or air-to-water heat pumps showcase remarkable efficiency, making them a vital tool in achieving sustainability and reducing environmental impact. 


You can learn more about air-to-water heat pump installation and maintenance here, where you’ll get an overview of what it entails.  


To see which Hitachi heat pump system is right for you, explore the heat pump range here.  


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