What is a semi-closed greenhouse?

A semi-closed greenhouse combines natural ventilation with active climate control. Outside air is introduced and conditioned in a controlled manner, allowing temperature, humidity, air movement and CO₂ levels to be managed more precisely. This gives growers greater control over the conditions surrounding the crop.

What is the difference between a semi-closed greenhouse and a traditional greenhouse?

A traditional greenhouse controls the climate largely through natural ventilation via roof vents. A semi-closed greenhouse also uses mechanical ventilation, positive pressure and air treatment. As a result, the greenhouse climate is less dependent on outdoor conditions and can be kept more stable.

How does a semi-closed greenhouse contribute to energy efficiency?

Because less heat and supplied CO₂ are lost through open vents, energy and CO₂ can be used more efficiently. Technologies such as air mixing and heat recovery can further optimize energy use. The actual savings depend on factors including the climate, greenhouse design, crop and energy supply.

Does a semi-closed greenhouse result in higher crop yields?

A semi-closed greenhouse can create conditions that support stable and predictable production. A more consistent climate and more precise climate control can contribute to crop growth, quality and production reliability. The final yield remains dependent on factors including the crop, cultivation strategy, location and operational management.

When is a semi-closed greenhouse an attractive option for a large-scale horticultural project?

A semi-closed greenhouse is particularly attractive when climate control, energy efficiency, water use and production reliability are important factors in the business case. For large-scale growers and investors, the local climate conditions, available energy sources, crop and desired production output should therefore be assessed together. KUBO tailors Ultra-Clima® to these specific conditions.

What is the difference between a semi-closed and a fully closed greenhouse?

A semi-closed greenhouse combines mechanical ventilation with limited natural ventilation options. A fully closed greenhouse has no roof vents and relies entirely on air conditioning. KUBO’s Ultra-Clima® is a semi-closed system that provides optimal climate control without the high costs associated with fully closed climate systems.

How much energy can I save with a semi-closed greenhouse?

Research shows energy savings of up to 18.5% compared with conventional greenhouses. The exact savings depend on the location, crop, heating system and energy sources. KUBO’s Ultra-Clima® also achieves more than 25% lower CO₂ emissions per kilogram of produce.

Which crops are suitable for a semi-closed greenhouse?

Semi-closed greenhouses are highly suitable for fruiting vegetables such as tomatoes, peppers and cucumbers, as well as ornamental crops and specialty crops. KUBO’s Ultra-Clima® technology is optimised for five to six crop types that together account for 95% of the fruit and vegetable market.

How does positive pressure affect crop protection?

Positive pressure of 10 to 20 pascals causes air to flow outwards when doors are opened. This makes it more difficult for insects and spores to enter. KUBO’s Ultra-Clima® system effectively keeps pests out and significantly reduces the need for chemical interventions.

Can I use residual heat in a semi-closed greenhouse?

Absolutely. Semi-closed systems work very well with low-grade heat at around 40°C. This creates opportunities to use residual heat from industrial processes or power plants. KUBO has completed projects in which these low-cost heat sources significantly reduce energy costs.

What is the main limiting factor for crop growth in winter?

Light is the primary limiting factor during the winter months. In the Netherlands, greenhouses receive only 10–15% of summer light levels in December. This directly limits photosynthetic capacity. KUBO’s Ultra-Clima® optimizes the use of available light by creating stable climate conditions that minimize crop stress.

How much energy can be saved with modern greenhouse systems?

Semi-closed greenhouse systems can save up to 18.5% in energy compared with traditional Venlo greenhouses. KUBO’s Ultra-Clima® achieves this through heat recovery, efficient cooling and smart ventilation systems that recycle heat instead of releasing it outdoors.

Can I grow year-round without fossil fuels?

Yes, this is possible with the right infrastructure and strategy. KUBO’s CO₂-negative cultivation strategy combines residual heat, efficient climate control and smart CO₂ utilization. This results in a cultivation system that captures more carbon than it emits while maintaining high yields.

How can I prevent pests in my greenhouse without chemicals?

Semi-closed greenhouse systems use positive air pressure to keep insects out. KUBO’s Ultra-Clima® creates a physical barrier against pests. Combined with biological pest control and good hygiene practices, this makes pesticide-free cultivation achievable for many crops.

What does switching to high-tech greenhouse horticulture cost?

The initial investment in an Ultra-Clima® greenhouse is higher than in a traditional Venlo greenhouse. However, lower operating costs, higher yields and reduced energy consumption result in an attractive long-term return on investment. KUBO provides tailored advice to help you find the best balance for your specific situation.