# Development of a Wireless System to Control a Trombe Wall for Poultry Brooding
## 1 Introduction  
A brooding house is a building that simulates the growth of chickens without their progenitor, from the day of the hatch to an age of about four weeks. Water, food and warmth are the most important factors during this stage in order to make them healthy and increase their development. This brooding house tries to replicate the temperature conditions that characterizes the time when chickens are under the mother's care. Some studies state that the maximum temperature for this type of brooding is 35 \({}^{\circ}\)C [1, 2]. It is very important to control these factors during these stages of the bird's life, given that it is when a higher number of deaths is registered comparing with the rest of the chicken's life stages. Balanced temperatures are a huge component to consider in order to regulate the mortality rate and the corporal and physiological development of the chickens [1, 3]. Several systems can be used to maintain the required temperature comfort in these buildings. In some countries, poultry farmers use kerosene stoves to deliver heating to the brooding houses. However, this has its downsides: the kerosene is highly expensive, can easily result in a fire, and burning it results in the release of carbon monoxide (CO) and carbon dioxide (CO2), which are environmental pollutants. Some farmers also try to usethe electrical grid to heat up the environment where chickens are; however, the system is expensive, not everyone has access to it, and there could be power outages, which makes the system unreliable. Both methods result in a high mortality rate and therefore a low production level. Consequently, these methods induced a production expansion to comply with the society needs, leading to environmental and socioeconomic problems [3]. There is the urge to develop an alternative method in order to maintain productivity by reducing death mortality. It should exist in abundance and be more reliable and environmental friendly. Taking into account these requirements, some improvements can be applied in building construction to make them more efficient and sustainable. The use of renewable energy, such as solar energy, can be a suitable solution [1]. The use of passive solar techniques, such as materials with high heat storage capacity, can be an option. Some studies show the use of a water tank located on top of the building, sensible to solar heating, that would easily diffuse that warmth to the brooding. However, this system can compromise the building structure and therefore would not be a suitable solution. Taking into account the disadvantages of those solutions, the use of a Trombe wall system was presented as an efficient one in some studies developed in this field [1, 2, 3, 4]. A Trombe wall is a high thermal inertia wall that presents a great capability of storing heat and gradually releasing it to the environment. The system is composed by a massive wall with air vents and a glazing outside separated by an air gap, leading to a greenhouse effect that improves the wall heat storage capacity. The solar radiation is received by the wall through the glazing and then converted into heat, which can be more quickly or slowly transferred into the brooding house, depending on whether the air vents are open or closed. When the air vents of the massive wall are closed with XPS boards (nonventilated Trombe wall), the stored heat is gradually released through the massive wall by radiation, conduction and convection. When the air vents are open, an increase in heat transfer is obtained by air convection through the ventilation system (ventilated Trombe wall) [5, 6, 7]. These vents allow for the air circulation between the wall and the glazing to the chicken brooding house. Trombe wall has an excellent thermal conductivity that allows for the reduction of temperature fluctuations inside of the poultry brooding house [3, 8]. The purpose of this work is to control the opening and closing of the massive wall air vents in order to maintain optimal and less fluctuated temperatures inside the brooding house.