water source heat pumps

What is a water source heat pump and how does it work?

Heat pumps are a great eco-friendly alternative to traditional heating systems like boilers, which is why a lot of people are making the switch. There are a lot of different types of heat pump, but this article will focus on water source heat pumps. So, what is a water source heat pump, how do they work, and what are the benefits?

How Does A Water Source Heat Pump Work?

A water source heat pump uses a series of pipes that are submerged underneath the body of water. Inside the pipes is a fluid that absorbs heat from the surrounding water and then boils. The refrigerant that is used can boil at temperatures lower than 0 degrees. The resulting gas is then carried back to a compressor. When the gas is compressed, it increases the temperature even further, and then it is passed through a series of heat extraction coils. This process is then repeated over and over. 

The heat that is extracted by the coils can then be used to heat water in the same way that a boiler normally would. This means that you can use it to generate hot water and run your central heating system. 

Different Types Of Water Source Heat Pump

There are a number of different types of water source heat pump. The system described above is known as a closed loop system where the same refrigerant is cycled through a closed loop of pipes. 

However, you may also use an open look water source heat pump. Water is drawn into the pump, where it is heated and the heat is distributed through your home. Then the water is discharged into the body of water again. These systems can be more efficient, but you may need permission from environmental bodies before you can recycle water in this way. 

Hybrid systems use a water source heat pump alongside another heating system like a boiler or solar panels. These are well suited to older homes that may not be very well insulated because a water source heat pump may not be sufficient to heat the home on its own. 

What Are The Benefits Of A Water Source Heat Pump?

Now that we have answered the question of what is a water source heat pump and how it works, we can look at some of the great benefits of installing one in your home. 

When compared with traditional heating sources like boilers, water source heat pumps are far more efficient. That means that you will save a lot of money on your home heating costs and reduce your impact on the environment at the same time. 

There are a lot of different types of heat pump, and they are all more energy efficient than traditional heating systems. However, water source heat pumps are the best of all of them. The average temperature of a body of water is somewhere between 7 and 12 degrees, and this stays constant throughout the year. Water is also more effective than air at transferring heat, so water source heat pumps are more efficient than air source heat pumps. 

Ground source heat pumps generate a good amount of heat, but they can be quite invasive to install. You will need to dig large trenches to install pipes, which is a lot of work and you will need a good amount of outdoor space. However, there is no digging required when installing a water source heat pump, and submerging the pipes is relatively simple. 

As long as you have a large enough water source near your home, you could benefit from installing a water source heat pump. However, it is important that the water source is large enough that it maintains its temperature all year round. Smaller water sources are prone to freezing, and that will stop your heat pump from working entirely. The larger the water source, the more heat you will generate, so consider the size of your home compared with the size of the water source. Ideally, you will need a lake or a river to heat a large home. 

If you have a water source near to your home, you should consider installing a water source heat pump because it is a great way to save money on heating costs. 

How much does a water heat pump cost?

A water source heat pump will cost around £10,000 to setup with a repayment period of 5 years, this is a higher cost than ground and air type heat pumps. We can, however, reduce the cost of your installation by comparing local installers quotes and helping you save hundreds on installation.

Once you’re up and running with your water source heat pump there’s less reliance on electricity saving you around 50% on electricity bills so making this investment is worth it in the long run, especially if your home is adjacent to a river or stream and if your property is well insulated you can gain the maximum benefits.  General maintenance must also be considered as it could increase the lifespan of your heat pump from fifteen to fifty years.

Grants available for water source heat pumps

To aid in covering the costs of installation the Government provides grants for those interested in using renewable heating in there home through their Domestic Renewable Heat Incentive (RHI) scheme. Payments are provided throughout a seven-year period and vary in amount based on renewable energy that is produced in the household. Water source heat pumps are potentially provided under the same funding category as ground source heat pumps. To apply visit ofgem.gov. Before starting the application you’ll need:

  • A Microgeneration Certification Scheme (MCS) certificate number this is to unsure the installation was carried out within the proper parameters. 
  • An Energy Performance Certificate (EPC) number  
  • Your bank details. 

Additional information is needed once you’re successful in obtaining your grant. These include:

  • Figures regarding the cost of installation 
  • How much you were paid 
  • The date you were paid
  • For the use of a heat pump energy based system you will also need to provide the Seasonal Performance Factor (SPF) which displays the effectiveness of your system.

For an average four-bedroom detached house the RHI scheme could offer between £2,325 and £3,690 a year. The overall outcome for a homeowner willing to invest in a water source heat pump results in a substantial amount saved on energy bills. In contrast to a conventional gas boiler, a heat pump could save you between £395 and £2,000 a year.

There are various different types of water pumps depending on your type of home and its location. If you live close by to a river or lake then a Closed-Loop Water Source Heat Pump System is the best and most affordable option if the household is within close proximity to a water source. This involves having a pipe connecting the building to the water that interweaves into circles of at least 8 feet under the surface to avoid freezing. The coils need to be positioned within the necessary limits of volume, depth and quality of the closest water source.  

In an open-loop system the water flows through the pipe producing heat, which then travels back to its source. These can be more beneficial than closed-loop pumps, but you need to gain approval from either the Environment Agency, for England or Wales, or the Scottish Environment Protection Agency (SEPA) to utilise this system to obtain the proper clearance. To ensure the lake or river is clean a filter can be installed to maintain water quality. Otherwise, the water needs be clear from its source.

Overall if your household meets the requirements of having a water source heat pump fitted it is definitely worthwhile due to the increased urgency in using sustainable energy to power our homes and with gas prices likely to increase now is the best time to switch to this eco-friendly alternative.     

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