Which energy-saving measures help reduce heating costs in greenhouses?

• A. Thermal screens and solar capture.
• B. Open doors during cold nights.
• C. Increase irrigation frequency.
• D. Remove insulation.

Answer: (A)

Reducing heating costs hinges on cutting heat loss and maximizing heat gain. Thermal screens act as an insulation barrier, reducing both convective and radiant heat losses when closed on cold nights, which keeps more warmth inside the greenhouse. They can also be used during periods of sun to balance light with heat retention. Solar capture involves collecting and storing solar heat to warm the space naturally, through well‑placed glazing, orientation, and materials that store heat (like thermal mass). Together, these approaches lower the need for artificial heating.

Open doors during cold nights invites cold air in and wastes heat. Increasing irrigation frequency doesn’t save energy for heating and can even raise cooling needs due to higher humidity and evaporative cooling. Removing insulation increases heat loss, raising heating costs.