Energy efficiency is not just low-hanging fruit; it is fruit on the ground. Stephen Chu, US Secretary of Energy
  • Minimum pipe temperature set points are used to force heat into a greenhouse even if it is not required to maintain the required greenhouse temperature.
  • In this factsheet, Farm Energy Centre's Chris Plackett, and Steve Adams and Allen Langton from Warwick Horticultural Research International (HRI) highlight the energy savings that can be made through effective glasshouse temperature.
  • Using degree day analysis enables you to account for weather and greenhouse temperature influences when looking at your energy use. 
  • Avoiding condensation on plants is a key part of any disease control strategy. Poinsettia growers have to pay particular attention to this problem as they use a technique to control plant height called ‘Drop’. ‘Drop’ involves reducing the greenhouse temperature to as low as 12 degrees C before sunrise and is followed by an increase in the greenhouse temperature to the daytime set point within one hour after sunrise.
  • We all know that colder weather means we use more energy for greenhouse heating. But how do we know if any increases in energy use are just down to the weather, or perhaps to other factors making us less efficient? This is where a technique known as 'degree days' can help.
  • Reducing minimum pipe temperature settings is a good way to save energy. However, this must be done alongside well considered ventilation settings to ensure that heating requirements are minimised.
  • In recent years, the accepted norm for growers of edible crops such as tomatoes, cucumbers and peppers has been to control humidity based on humidity deficit (HD). This is because conventional wisdom suggests that maintaining a minimum HD promotes transpiration, which, in turn, ensures optimised plant development and growth.
  • When growing greenhouse crops, it’s sometimes desirable to use a little more heat than strictly necessary to maintain adequate growing conditions. The purpose of this is to keep conditions comfortably away from those which could, for instance, trigger a disease problem.