FEC have recently completed an HDC funded research study in Holland into closed green house systems. Whilst the closed green house systems used in Holland, utilising underground aquifers, would not be technically feasible for use in the UK, some of the technology involved – fans, ducts and heat exchangers - could deliver significant benefits on a range of crops.   Fans and ducts alone will improve air movement and therefore the uniformity of temperature, humidity and CO2 within a greenhouse. The likely benefits

would include more uniform crop development and easier CO2 use; and reduced pest and disease incidence through reduction in ‘hot spots' and ‘incubator areas’. Incorporating a heat exchanger would deliver extra benefits, many of which stem from using lower temperature water for heating such as improved boiler efficiency and reduced heat distribution losses and the ability to use low grade CHP heat that is commonly wasted. Further to the findings of FEC’s research, HDC is currently considering a new project to explore fan- and duct-based environmental control systems in much greater detail on a commercial nursery.