What Is a Water Source Heat Pump?
Water source heat pumps (WSHP) move heat from a source of water to your household more efficiently than any other heating and cooling technology. A river or a small stream can be pumped through a heat pump, and it can deliver excellent results, especially if the water temperature is somewhere around 5 to 8 degrees celsius.
This kind of technology has been used since the late 1940s. Water source heat pumps use the rather constant temperature of water as an exchange medium instead of extracting the heat from the outside air temperature. Thus, the system can reach reasonably high efficiencies (300% to 600%) on the coldest winter nights, in comparison to 175% to 250% for air source heat pumps on cool days.
If this sounds too good to be true and you are interested in buying a water source heat pump, we are here to make your buying process easier. You can avoid researching for different suppliers by simply filling the contact form on the right with your details and needs. We will receive your request and provide you with free, no-obligation quotes from up to 4 suppliers.
Pros of Water Source Heat Pumps
- They generate less CO2 emissions than conventional heating systems.
- The Energy Saving Trust (EST) estimated that such a heat pump could save you between £395 and £2,000 a year depending on which heating system you replace.
- The RHI scheme offers payments to homeowners who have a heat pump, estimated between £2,325 and £3,690 a year for an average four-bedroom detached home.
- Electricity must be used to power the pump which circulates the water through the loop, which results in every unit of electricity used by the heat pump, you receive between two and four units of heat, thus making this an efficient way to heat a building.
Read More: Water Source Heat Pump Cost
How Do Water Source Heat Pumps Work?
The system is made of fairly efficient reverse cycle heat pump units which are interconnected by way of a water loop. Every unit offers specific air comfort requirements in the particular zone they are installed. During cold weather, the heat pumps transfer heat from a water loop through the unit’s specially designed refrigerant-to-water heat exchanger and then move it into the air.
In extreme weather conditions, when a lot more heat is necessary to warm up the building, units are operating in heating mode, hence heat is provided to every individual unit from the water of the loop. In case there isn’t enough heat in the loop water, an energy efficient fluid heater must be installed in the loop in order to assist the heating process.
Ideally, the water source should be close to the house, so that it would not need to be pumped up at any significant height or the energy required for pumping could be decreased, thus increasing your savings. Water can be sourced from substantial distances if the pipe diameter is adequately big, especially in a downward direction. When considering installing such a device, you must take into account the permissions and paperwork that must be completed in order to start your installation.
You can check this by visiting the page heat pumps in the UK and browse for your area and the city closest to your position.
Types of Water Source Heat Pumps
If around your household there is a sufficient water body, this is definitely the lowest cost option. A supply line pipe goes through the ground starting from the building to the water and intertwine into circles of at least eight feet under the surface to avoid freezing. Coils must be placed in a water source which meets the minimum requirements in matters of volume, depth and quality.
This system utilises a well or a surface body water while the heat exchange fluid goes through the heat pump system. Once it dispersed through the whole system, the water returns to the ground via the well, a recharge well, or a surface discharge. Unfortunately, this option is practical only where there is a reasonable supply of clean water, and at the same time all regulations and codes regarding groundwater discharge are completed.
These types of systems use certain geothermal resources, or a mix of geothermal resources with the outdoor air. Hybrid systems make the most sense where cooling needs exceed those of heating. For example, where local geology permits, a “standing column well” this should be your prefered choice. This variation of open-loop system requires one or more deep vertical wells. Water is brought from the bottom of a standing column and returned to the top. Regardless of period, either heating or cooling, the bleed cycle system cools the column while heat rejection, heats it during heat extraction, and also reduces the necessary bore depth.
Financial Incentives - RHI
Since there is a growing importance in producing and using renewable energy solutions, the UK has started motivating businesses, organisations and people alike to increase their use of renewables and to reduce CO2 emissions. Starting mid-2011, the Renewable Heat Incentive (RHI) started providing funds to engineers of small or medium installations that deliver an acceptable heat load and meet a minimum energy efficiency standard. From 2004 to 2010, energy prices have increased by 50% (gas) to 80% (electricity) , moreover it is expected for gas prices to escalate quicker than electricity prices.
There are certain environmental regulations and considerations that must be addressed before installing a water source heat pump. Open-loop systems alter the temperatures of groundwater, while thermal plumes affect hydrochemistry and bacteriology. Depending on the type of system you wish to install, licenses may be required. For example, hydrogeology and thermal properties have to be investigated, and they require a license to investigate groundwater, and an abstraction license (permission of diverting surface or ground-water) which can be obtained from the Environment Authority.
Water heat pumps work by using underground aquifers as both a heat source during winter and a heat sink in the summer. Aquifers offer good heat conductivity, stable temperatures and large capacities for heat storage, thus providing you with energy efficient heating and cooling and a reduced carbon footprint. In the UK, there are plenty of well-suited aquifers for water heat pumps.
Estimates show that ground source heat pumps can produce up to 30% of UK’s heating needs. This has been possible due to new developments in the field of renewable energy, lowered installation costs and the Renewable Heat Incentive. All of these have created huge interest in ground source heat pumps in general, especially in the London area, with an estimate of 1,000 applications for open-loop systems in particular.