The first model greenhouse heated with geothermal energy, set up in Lampa, Chile, has obtained positive results thanks to the co-funding by the Foundation for Agricultural Innovation (FIA) of the Ministry of Agriculture, with resources from the Innovation for Competitiveness Fund of the regional government.
One of the goals of the initiative, developed by the agricultural entrepreneur Sergio Aguilar, is to establish the use of geothermal heat pumps to control temperature in a dynamic way and optimise heat management in the greenhouse. In Chile, this type of technology has only been used for residential environments and some industrial applications.
The project has so far allowed "the control of high temperatures in watercress hydroponic beds, with a noticeable improvement in the crop," says Abdo Fernández, coordinator of the initiative.
The production of greenhouse crops requires thermal regimes with low variability and minimum temperatures higher than 12ºC. Below this level, the growth rate of vegetables and flowers slows down, symptoms of damage appear and productivity is affected.
The same happens with temperatures higher than 28ºC; consequently, heat regulation helps control the growth and development of the crops, allowing for the production to be programmed through low-temperature geothermal energy.
This technology is usually considered a half-way step between energy efficiency and non-conventional renewable energy, despite using energy from the ground and the sun, it requires electric power to work.
Cost savingAbdo Fernández explains that the system being tested pumps water from a well through a machine. This water enters at around 15ºC and is immediately returned at around 8ºC whenever heat needs to be generated. When the goal is to lower the temperature, the water is returned at temperatures 3 to 4ºC higher.
"This is how the temperature of the water from the heat storage system is regulated. This water is then distributed through the greenhouse's environmental control systems, and in the case of hydroponic beds, we have already obtained quite good results."
It has been estimated that the use of geothermal energy could reduce energy costs by up to 50% compared to traditional heating methods.
The goal is also to assess whether the use of this system is environmentally convenient, reducing the amount of primary energy used to achieve an intensive greenhouse production, and thereby reducing the global carbon footprint for such crops.
The initial results of the initiative, which required a 55.5 million peso investment, will be announced by the end of this year's second quarter.
Source: FIA
The goal is also to assess whether the use of this system is environmentally convenient, reducing the amount of primary energy used to achieve an intensive greenhouse production, and thereby reducing the global carbon footprint for such crops.
The initial results of the initiative, which required a 55.5 million peso investment, will be announced by the end of this year's second quarter.
Source: FIA