Crop type, scale, greenhouse design, budget, and other project variables all need to be taken into consideration for a well designed heating system in a greenhouse. Below are four key areas for comparison that can help determine which heating style is a good fit for your greenhouse heating project.
1. Capital expenditure
Typically, boilers have higher capital expenditures than unit heaters due to associated system costs such as radiant heat pipe systems, heat storage tanks, etc. These costs can vary widely based on scale of application as well as the project’s specific design parameters. In some cases for larger projects, boilers can be more competitive with unit heater systems due to improved scalability.
2. Energy efficiency
Both unit heaters and boilers have a range of efficiencies depending on the type, manufacturer, and system design, but generally boilers have the edge with higher energy efficiency and distribution efficiency than unit heaters.
Control: Unit heaters are typically easier to operate with simple control systems and integration. While boiler systems can be more challenging to operate, they have a higher level of controllability which has two major benefits; one, advanced controllability allows for more efficient operation of the system, building on the simple thermal efficiencies of the systems. Two, better control leads to a better environment which can have many benefits for your production.
Distribution: When combined with a radiant heat system, boilers distribute heat more efficiently and uniformly than unit heaters. Unit heaters can be combined with a well planned HAF layout, or duct socks which improve heat distribution, but still lack in comparison to radiant heat systems causing hot and cold spots in the greenhouse.
Both unit heaters and boiler systems are important to maintain properly for optimal performance overtime, but generally boiler systems have a longer lifespan than unit heaters in a greenhouse environment.