What Is a Hot Water Heater?
In a greenhouse, a hot water heater is a system that heats the space by circulating hot water through pipes installed within the greenhouse. This water is heated by a boiler or similar device, and the rising warm air from the hot water creates a stable, uniform heating environment.
Uses of Hot Water Heaters
Hot water heaters are commonly used in greenhouses for high-value crops like orchids and greenhouse melons, where precise temperature and humidity control are crucial. However, they are less suitable for crops like strawberries and tomatoes that do not benefit as much from this type of heating.
Due to their high equipment costs, hot water heaters are typically used in larger facilities or for crops that command higher market prices.
Characteristics of Hot Water Heaters
Advantages
1. Temperature and Humidity Control: Hot water heaters can maintain moderate humidity levels and gradual temperature changes, ensuring uniform growth of crops.
2. Reduced Air Current Impact: The gentle airflow produced by hot water heaters minimizes the impact on sensitive crops.
3. Residual Heat: These heaters retain a significant amount of heat, providing temperature stability even in the case of equipment failure.
Disadvantages
The primary disadvantage is the high initial cost, making it an investment that needs careful consideration based on the expected return and the size of the facility.
Types of Hot Water Heaters
Hot water heaters can be categorized based on their fuel source:
1. Fossil Fuel-Based Heaters:
These heaters use fossil fuels like oil and are known for their high energy efficiency and ease of storage and transportation. However, the rising costs of fossil fuels and environmental concerns are shifting the preference towards biomass-fueled heaters.
2. Biomass-Fueled Heaters:
Biomass heaters, using renewable resources like wood chips, help reduce carbon dioxide emissions and can be a cost-effective alternative.
How to Select a Hot Water Heater
When selecting a hot water heater, consider the optimum temperatures for both crop growth and insect activity, especially when insects are used for pollination or as natural predators. It’s also important to weigh the initial investment against the potential returns from the crops being cultivated.