New technologies are helping an environmental construction company create a zero carbon home that it claims will use less than 2kW of energy. Greenway Developments’ cost-competitive concept, which it is estimated will use just 1.7kW of energy to heat efficiently, is already being met with an ‘incredible’ reaction from social housing providers in particular.
Key elements in reducing energy consumption in the home once occupied are insulated concrete form (ICF) bricks, rainwater harvesting, photovoltaic tiles, and Passivent’s new GenAiration intelligent mechanical ventilation with heat recovery (MVHR). The latter also has a positive impact on construction techniques and time, as GenAiration has utilised Passivent’s innovative SRD75 small bore ducting, which, due to its flexible construction can be fitted round corners without the need for additional joints.
Frank Hesketh, Greenway Developments Ltd sales and marketing director, observed: “Passivent’s GenAiration will make a significant impact to both housing provider and occupier. It is quicker and easier to install than conventional MVHR systems, and once installed is completely automatic, which takes operation away from the tenant. We have had an incredible reaction to the house and all its technologies from housing associations, and are already in advanced discussions to provide over 300 units.”
Passivent GenAiration centres around humidity sensitive extracts in each room coupled with a self-regulating airflow system to ‘intelligently’ ventilate only as, where and when needed, without any occupier input. The humidity sensitive extracts in each room sense when ventilation is needed, opening to increase extraction in that zone only. Traditional MVHR systems rely on screw type valves which can significantly affect performance if adjusted incorrectly by the occupant. GenAiration avoids this problem by providing fixed valves where the position is set during installation. without any occupier input.
Further, Passivent GenAiration maintains a constant fan speed to achieve effective whole-house ventilation, reducing energy consumption as there is no increase in fan speed as extraction is boosted. Passivent product manager, Dennis Bates adds: “From our research, there are issues with traditional MVHR, especially from social landlords. The valves in each room have to be accurately set at the initial installation/ commissioning stage, which is a time-consuming process. Altering one throws the whole balance out. Once installed, as/when the system is boosted, it is not able to recognize in which room the extra ventilation is required. It therefore instead boosts the extraction rate in all rooms, whether they are occupied or not, using more energy than actually needed.
“Further, real-life experience shows tenants do not operate the system at all, or they close the valves because of perceived draughts in habitable rooms and of concerns regarding cost savings.. Lack of adequate ventilation can have major lifetime cost implications, causing condensation and damp that affect the building fabric and the occupants’ health. Adjusting any of the valves throws the whole balance of the system, causing it to run inefficiently.”
GenAiration is the latest development in energy-efficient domestic ventilation from Passivent. The company supplies a comprehensive range of natural and mechanical background and ‘whole house’ systems, from through- wall and window tricklevents to ‘intelligent’ passive stack and mechanical ventilation solutions.