Case Study – New build has the full package

Location: Halkyn, Flintshire

Brief: Hafod were appointed to undertake the renewable and heating installations at Andy Woods new build property in Halkyn.  The client wanted to ensure he installed  the best low carbon systems to ensure he is as self-sufficient as possible.

Execution:  Hafod designed and installed Ground source heat pump system to a warm water underfloor heating system.  The rear garden of the property was deemed not large enough for horizontal collectors so Hafod worked alongside Dragon Drilling to install 3 boreholes at an average depth of 80 meters each.   The ground source heat pump provides 100% of the heating and hot water.  The ground source system is designed to operate at 35 degrees for the heating and will heat the domestic hot water up to 60 degrees which is plenty hot enough for baths and showers.  A 200 litre hot water storage cylinder was selected for domestic hot water use which ensures the client will never run out of hot water.

Technologies installed

  • Underfloor Heating using Uponor MLCP underfloor heating pipework laid on 120mm Kingspan Phenolic Insulation.  70mm Sand and cement (mixed with fibres) was laid on top of the pipes to make up the finished floor.
    For the edge insulation, we used Kingspan insulation as an upstand ( 1 inch).  We then taped 10mm foam onto this to provide expansion for the solid floor to allow for changes in temperature.
  • Ground Source Heating system using Nibe 8 Kw Ground to water heat pump with a 200 litre buffer & 200 litre thermal hot water cylinder with a solar coil.
  • Solar Thermal system comprising 2 panel Dimplex flat plate solar collectors (in roof)
  • Solar PV System using 2 kw consisting of 7 x 285w SunEdison All black Monocrystaline modules, Growatt 2000TL Inverter
  • Rainwater harvesting off the roof collects in a 3500 litre storage tank(s), pumped to an elevated cistern via a submersible pump and then fed by gravity to the points of use.

Customer benefits

  • The Customer will benefit from low heating costs due to the ground source heating being designed for optimum low flow temperatures.   The  Borehole ground heat pump is the most effective system due to the rock constant temperature of 10 – 12  degrees  .  The solar hot water panels will provide approximately 60% of the properties domestic hot water use
  • The Solar PV system will also help to run the Ground source heat pump.  The combined approximate savings over oil is £300 per annum
  • The Renewable heating incentive will earn the customer £500 per annum
  • The feed in tariff will earn the customer approx. £400 per annum
  • The carbon footprint for the dwelling is dramatically reduced by using electricity from the solar panels and utilising renewable heat from the bedrock.