First reduce demand as much as possible through architectural passive measures appropriate to local climate, site constraints & building use which:
> Minimises heating loads by reducing thermal losses from building fabric & uncontrolled air leakage, while using passive solar gains where appropriate.
> Minimises cooling loads by reducing thermal gains, especially solar gains through appropriate levels of glazing & shading
> Maximises use of passive cooling, from the free cooling of natural ventilation, night time ventilation & exposed thermal mass
> Maximises use of natural daylight to reduce use of artificial lighting.
Secondly, reduce demand through careful choice of energy efficient plant & equipment which:
> Uses low grade heat/ energy to minimise high grade energy generation
> Maximises equipment efficiencies to reduce amount of delivered energy required to satisfy energy demand
> Adopts controls which only allow equipment & fittings to be active when required, to reduce power consumption
> Provides adequate occupant adaptive controls to extend occupants thermal neutral zone & reduce energy demand
Finally, only when demand has been reduced as much as possible should low carbon & zero carbon decentralised energy generation options, appropriate for the required energy profile & location, be assessed to provide as much of the remaining energy demands required, in order to progress towards zero carbon solutions.