Energy efficiency is not just low-hanging fruit; it is fruit on the ground. Stephen Chu, US Secretary of Energy
  • 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.
  • Using degree day analysis enables you to account for weather and greenhouse temperature influences when looking at your energy use. 
  • The graph below shows energy use over the course of a day in February at R&L Holts (one of the GrowSave Focus Nurseries). It is a perfect illustration of how things should operate when a thermal screen is set up correctly!
  • This article explains some set points you can use with your climate control computer to control when your greenhouse screens open and close in relation to time of day and light level..
  • 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.
  • 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.