Quick answer: The cost of dehumidifying a greenhouse is set mostly by the night moisture load (crop, area, temperatures), which fixes how much capacity you need, and then by how the dry air is distributed, corrosion protection, controls integration, power and drainage work, and running hours. Two greenhouses of the same area can need very different systems. Ask suppliers to quote against the same night load and condition, and compare installed cost plus energy per season, not unit price alone. Running cost is roughly power × hours × electricity price, offset by the heat the dehumidifier returns to the house.
Quick answer
- Biggest driver: capacity needed at the night condition.
- Then: distribution (ducts, air tubes), coatings, controls, electrical and drainage.
- Compare offers on the same load, condition and scope.
Equipment cost drivers
| Driver | Why it matters |
|---|---|
| Required capacity at night condition | Ratings at 30 °C / 80 % RH overstate removal at 16–18 °C night conditions, so more rated capacity is needed |
| Number and size of units | Several medium units spread through the house cost more than one large unit but dry evenly and give redundancy |
| Technology | Refrigerant for most heated houses; desiccant or hybrid only for cold houses or strict targets |
| Corrosion protection | Coated coils and corrosion-resistant casings for fertiliser, sulphur or coastal air |
| Ducted vs freestanding | Ducted units feeding air tubes add duct cost but improve distribution; see ducted vs freestanding |
| Controls | Interface to the climate computer, sensors, alarms |
Related: ducted vs freestanding.
Installation cost drivers
- Electrical supply (often three-phase), cabling and protection.
- Condensate drainage to drains or collection tanks.
- Mounting: floor, hanging from structure, or plant room with ducts.
- Air tubes or ducting.
- Commissioning and integration with the climate computer.
Running cost
Night cost ≈ total power (kW) × hours running × electricity price
Example (illustrative): two RYCF-22S units with a maximum input of 8.4 kW each, running at an average of 6 kW each for 10 hours, at €0.15/kWh: 2 × 6 × 10 × 0.15 = €18 per night.
Offsets:
- Returned heat: the condensation heat (about 0.68 kWh per litre) plus the electrical input go back into the house, reducing heating.
- Less venting: heat and CO₂ stay in.
- Fewer losses: less disease and crop damage from wet nights.
See industrial dehumidifier running cost and heat-recovery ventilation vs dehumidification.
How to get comparable quotes
Send every supplier:
- greenhouse area, height, spans and screens;
- crop, stage and planting density;
- night temperature and humidity now, and the target;
- heating, venting and CO₂ strategy;
- power supply and drain points;
- how dry air should be distributed.
Ask each to state capacity at your night condition, power input, number and placement of units, and what is included in the scope. Our greenhouse moisture load calculation and how many dehumidifiers a greenhouse needs explain the inputs; see our greenhouse dehumidifiers.
FAQ
Frequently asked questions
How much does a greenhouse dehumidifier cost?
It depends on the capacity needed at your night conditions, the number of units, distribution, coatings, controls and installation. Send the inputs above for a project-specific quote.
How much does it cost to run a greenhouse dehumidifier?
Power × hours × electricity price; for example two units averaging 6 kW each for 10 hours at €0.15/kWh cost about €18 a night, partly offset by heat returned to the house.
Is one big dehumidifier cheaper than several small ones?
Often cheaper to buy, but several units spread through the house dry more evenly and keep working if one fails.
Sources
- ASHRAE Handbook—Fundamentals, Psychrometrics.
- Product data: Yakeclimate RYCF specifications.
