What is the development process?
We offer a free-of-charge initial assessment for all heat pump projects, to provide details of the expected performance and project finances.
After that, we will carry out a site survey to review the heating demand, emitter specifications and suitability of the watercourse.
Smaller projects (<100kW) typically take 4-5 months, including:
1. Site survey and EN12831 heat loss calculations
2. Detailed design (+ consenting if required)
3. Installation & commissioning
Larger projects (>100kW) typically take 7-9 months, including:
1. Site survey
2. Feasibility study
3. Detailed design & consenting
4. Installation & commissioning
Renewables First offers a ‘turnkey’ solution from start to finish. Our scope includes the heat pump, heat collectors, and the pipework between the two. We will advise your heating engineer to ensure that the internal heating and hot water systems work seamlessly with the heat pump.
Heat Pump Feasibility
Water source heat pump feasibility studies
Water-source heat pump systems, when designed and operated correctly, are relatively simple and are a highly efficient and low-emission way of heating a building. However, anything that uses natural ambient energy to heat a building is inevitably more complicated from an engineering perspective compared to a fossil-fuelled boiler, which has a much easier life because the clean fuel is simply delivered down a pipe. The fuel for a water-source heat pump is natural water and this often contains debris which if not managed carefully can block the system up. This water must be abstracted from the watercourse and conveyed to the heat pump which is normally located in or close to the building to be heated. The discharge water needs to be conveyed back to the watercourse and discharged without compromising (i.e. cooling down) the intake water.
The heat pump itself must be carefully ‘sized’ to make sure it is well-matched to the heat load of the building to be heated. For this to be done a heat load analysis on the building must be completed to accurately determine the space heating loads throughout the year. Also the heat emitters (radiators, underfloor heating etc.) in the building must be assessed to work out if they will work effectively with a heat pump system with flow temperatures of 35°C ( for underfloor heating ) or 45°C ( for radiators ) , and if they would not specify what upgrades would be needed. Once this is done the operational patterns from the building’s users must be understood (including cooling in summer if needed), then the heat pump can be sized and specified in detail.
Clearly all of this will require a site visit and building survey followed by a great deal of technical analysis, and for this we provide a standard water-source heat pump feasibility study service. The feasibility study includes:
| Assessment Type | Detail |
|---|---|
| Summary of the findings / recommendations | Brief executive summary of report and recommendations |
| Resource data | Watercourse flow analysis Watercourse seasonal temperature profile Seasonal air temperature profile Site layout and levels Cleanliness of the water source Chemical composition of water source |
| Building / heat-load assessment | Building heating demand survey / analysis ( Room By room Heat Loss Assessment to BS12831:2003 ) Review of current thermal energy use Existing heating system review Existing Heat emitter review (radiator, underfloor heating etc.) Comments on current thermal efficiency and potential improvements |
| System specification | Proposed system layout Heat pump sizing and system specification Energy production / consumption profiles Control system specification Integration with existing system |
| Details of Consenting requirements | Regulatory consents Planning consent Building Regulations considerations |
| Finances | Budget costs Running costs Comparison with existing / conventional heating system Payback / Return on Investment calculations |
| Recommendations and next steps | Detailed summary of all aspects of the report including recommendations for next steps |
A site visit would be carried out as part of the feasibility study.
The price for the water-source heat pump feasibility study depends on the size of the property to be heated and will be advised in the summary information of the Free Heat Pump Initial Assessment. It normally takes three weeks to complete the feasibility study.
Water source heat pump consenting
Regulatory consents are required for your heat pump
The main consent needed for a water-source heat pump is an Abstraction Licence in England and Wales, and a CAR Authorisation in Scotland. The regulators (EA in England, NRW in Wales and SEPA in Scotland) are generally supportive of water-source heat pump projects but they do have specific technical requirements in regard to volumes of water, temperature differentials and pollutant guidelines that must be met.
Planning consent is not normally required unless a new plant room would be built, or the water intake structure would be visible. Listed Buildings may require Listed Building Consent if any of the building fabric will be changed. As with any works in buildings, the Building Regulations must be adhered to.
Renewables First has a great deal of experience in dealing with the various regulatory authorities to obtain consents and would take care of this aspect of the project on behalf of our clients.
How is the heat demand calculated?
Accurate heat demand calculations are particularly important for heat pump projects, as it is expensive to oversize systems. For smaller projects, we will carry out heat loss assessments to EN12831, the standard required for MCS certification 1 . This will give a more detailed room-by-room heat load, which is more accurate than using EPC or SAP data.
We specify heat pumps based on their nominal output, which assumes the water source is at 0C. In practice, the minimum temperature is typically 6-8C, which allows a higher heat output. This provides a suitable safety factor to ensure the system can provide more than enough heat for the property.
Do I need planning permission for a heat pump?
Planning permission is not required for most water-source heat pump projects. However, in some cases it may be required, such as for listed buildings, or larger commercial projects.
Do I need consent from the Environment Agency / SEPA / NRW?
For domestic closed-loop systems, no environmental consents are required.
Commercial projects will require consent for any in-river works, and open-loop systems will also need an abstraction licence.
Renewables First has many years’ experience obtaining environmental consents, so we can help ensure this process goes smoothly.
How can I arrange a site survey for a heat pump?
If you are considering installing a water-source heat pump, please send us an enquiry here. We’ll provide you with an initial assessment of the project performance and finances, free-of-charge.
Water Source Heat Pump Design and Installation
Water Source Heat Pump Design
Water source heat pump design
The aim of the design stage is to turn the outline specification produced at the feasibility stage into a full system specification and set of drawings so the system can be built.
The main areas covered at the water source heat pump design stage are:
• Detailed specification of all Mechanical & Electrical (M&E) plant.
• Electrical installation drawings and specification (upgrades, power and signal wiring).
• Plant room layout.
• Intake system drawings.
• Integration with existing thermal systems / back-up and boost heating / supplementary heating.
• External pipe runs / trenches and ducting / pipe specification (for source water).
• Internal pipe runs in plant room (to heat distribution).
• Design of civil engineering / building works (if applicable for intake and/or plant room).
• Control system specification.
• Heat emitter specification – (note detailed design of this aspect would be done by the chosen plumber / heating contractor).
• Operational performance and financial modelling.
• Draft sequence of works / project plan.
• Construction Design Management (CDM 2015) documentation as the Principal Designer.
• Budget costing.
Water source heat pump installation
The extent of the work depends a lot on the type of building and size of the project. For a domestic water-source heat pump project the intake can be a small area created for a small pump that that pumps water to a primary heat exchanger and then the source water is discharged back into the watercourse.
Water Source Heat Pump – Electrical and Mechanical Installation
A pipe run then conveys the water to the heat pump location. If the heat pump is accommodated in an existing building no further building work will be needed and the remainder of the work is plumbing and electrical installation. Renewables First oversees the whole installation process and is responsible for the design being followed and the efficient operation of the finished system. We either use trusted plumbing and electrical contractors, or can work with your own plumber and electrician, which often has advantages if they already have a good understanding of your building.
Larger domestic and commercial projects often require a more substantial water intake structure because of the increased volumes of water used by the system. In-river constructions works are likely to be required, and with many years’ experience installing hydropower projects this is something Renewables First is very familiar with.
Water Source Heat Pump – Plant Room Construction
Also larger projects may need a larger or new plant room, which may require some building works. Again once the building works are completed the work moves into Mechanical and Electrical (M&E) installation and at this stage we use suitably experienced contractors or work with your preferred contractors. Once installed Renewables First will commission the water-source heat pump system and make sure it works efficiently in your building and provide ongoing support through our Operation & Maintenance (O&M) services.
1. MCS certification for Heat Pumps is provided through an umbrella scheme from Kensa Heat Pumps, where we are their installation contractor and are responsible for the design and efficient operation of the system. We can provide plumbing & electrical contractors or we can utilise your own local contractors.
2. Coefficient of Performance (CoP) will depend on the source temperature of the collector and the desired supply temperature. Please see the following link from the European Heat Pump Association (EHPA) for their verification of the likely CoP White_Paper_Heat_pumps-1.pdf(page 32).
Are you considering a water source heat pump project?
You can learn more about Heat Pump projects here, or contact us, and our engineers will guide you through your Heat Pump journey.