Demonstration of greenhouse summer high-temperature measures through drone application of heat-shielding materials

NTT e-Drone Technology Inc. (President and CEO: Masahiro Takizawa, hereinafter "the Company") conducted a demonstration experiment of applying heat-shielding materials using drones as a measure against high temperatures in summer for facility horticulture.

This demonstration confirmed that applying heat-shielding materials by drone can reduce the greenhouse temperature during the day by approximately 5°C on sunny days. Application using drones eliminates the need for high-altitude work on greenhouse roofs and contributes to high-temperature measures in summer as a means of uniform application.

1. Background and Objectives

In recent years, record high temperatures in summer have occurred frequently against the backdrop of global warming, and a major challenge for facility horticulture is the rise in greenhouse temperatures during the day, which affects crop growth and quality. As a measure against such high temperatures, applying heat-shielding materials to greenhouse roofs is attracting attention as a new option following conventional heat measures. A feature of heat-shielding materials is that they can be used in combination with existing high-temperature measures such as natural ventilation, shading curtains, and heat-shielding nets.

On the other hand, there were also challenges with the application of these heat-shielding materials. Manual application involved high-altitude work on greenhouse roofs, was strenuous labor requiring many people and long hours to apply uniformly over a large area, and tended to result in uneven application depending on the skill of the worker. Against this background, this demonstration was conducted at the farm of NTT Agri Technology Corporation (hereinafter "NTT Agri Technology"), a group company, to verify whether the application of heat-shielding materials using drones could help solve these problems.

2. Overview of Demonstration Experiment

Location

Chuo City, Yamanashi Prefecture

Facility Area

Approximately 1 ha

Aircraft Used

BB102 (using a set for disinfectant, deodorizer, lime, and heat-shielding material application)

Application Date

April 28, 2026

Measurement Period

April 28, 2026 - May 12, 2026

Measurement Method

Simple measurement using environmental loggers

3. Demonstration Results

Comparing the greenhouse temperatures between the application plot and the control plot, the temperature reduction effect during the day (9:00-16:00) was confirmed to be approximately 5.1°C on sunny days (10-day average), from approximately 33.8°C to approximately 28.7°C, and approximately 3.9°C on cloudy days (4-day average), from approximately 27.4°C to approximately 23.5°C. * The above figures are based on measurements conducted by our company and may vary depending on weather conditions, greenhouse structure, environment, etc.

<Greenhouse roof after drone application> Aerial images after application confirmed that the heat-shielding material was uniformly applied to the greenhouse roof.

Secondary findings were also obtained regarding the amount of material used. In this demonstration, the aforementioned temperature reduction effect was confirmed even when applying less heat-shielding material than the manufacturer's standard application rate. Based on these results, it is expected that the same heat-shielding effect as the manufacturer's specifications can be achieved with approximately 33% less material than the standard application rate. Further verification will be conducted on the optimization of usage amounts.

The "Green Food System Strategy" formulated by the Ministry of Agriculture, Forestry and Fisheries in 2021 sets goals for reducing the environmental impact of the entire food system, such as achieving zero CO2 emissions in agriculture, forestry, and fisheries by 2050 and reducing the use of chemical pesticides and fertilizers. We believe that the knowledge gained from this study, which achieves equivalent effects with the minimum necessary materials, can contribute to reducing environmental impact and optimizing material usage.

4. Features of the Application Method

Application was performed by attaching the disinfectant, deodorizer, lime, and heat-shielding material application set, which has been available since June 2026, to the "BB102" used in this demonstration. Drone application has its own challenges. Because the agent is sprayed from the air, fine particles are easily carried by the wind, leading to not only overspray onto unintended surfaces but also, under certain conditions, the risk of the material scattering and adhering to adjacent fields, the surrounding environment, and even third-party assets beyond the application target. In particular, atomizing methods (atomizer methods) that spray fine particles are known to be prone to such scattering.

To address these challenges, this demonstration adopted an application method that directly delivers the agent to the target surface from a pressure-discharge nozzle. This method is less prone to scattering to the surroundings compared to atomization methods and is suitable for applications where precise application to a target, such as a greenhouse roof, is desired. In addition, we are working on optimizing the particle size of the sprayed liquid. If the particle size is too small, it will drift in the air and scatter to unintended surfaces; if it is too large, adhesion and film uniformity will be compromised. We are developing optimal particle sizes and application conditions according to the characteristics of the material. Through these efforts, we have realized uniform application to the greenhouse roof while suppressing scattering to the surroundings by leveraging the unique advantages of drones.

5. Future Development

Based on the knowledge gained from this demonstration, the Company will propose drone application of heat-shielding materials as a new option for high-temperature measures in summer for facility horticulture and actively promote its widespread adoption. In the future, we will work with agricultural material manufacturers to establish optimal application conditions tailored to the characteristics of crops and materials, and strive to disseminate this service as an easy-to-use service for many producers.

Those interested in drone adoption, including inquiries and quotes, are welcome to contact us at the following address ([email protected]).

6. Comments

Comment from a representative of Salad Bowl Inc. based on this demonstration:

"Quality degradation due to high temperatures in summer is a major challenge directly linked to agricultural management. Furthermore, applying heat-shielding materials to greenhouse roofs has been strenuous labor requiring manpower and time. This demonstration showed that using drones enables short-time, uniform application, and we were able to confirm the numerical effect of reducing greenhouse temperatures. We look forward to its future dissemination and development as a new method that can reduce work load."

Inquiries regarding this matter from customers:

NTT e-Drone Technology Inc.

Service Promotion Department, Dissemination Division [email protected]