Heat management
Increased productivity and lower power consumption
Leif Barsballe, who is farm manager at A/S Dansk Landbrug, is responsible for an annual production of approx. 1.8 million broilers at a poultry farm near Hobro in Denmark. The farm consists of six livestock houses containing approx. 30,000 broilers in each house. The six livestock houses were built in three stages between 1991 and 1998.
A good livestock house climate is vital for the well-being, health, and productivity of the broilers. Heating is, like ventilation and cooling, an integral part of a climate solution, and crucial for creating the best possible livestock house climate with a high level of productivity.
It is important to heat the livestock house before stocking the broilers because it gives the broilers and the litter the best possible start. The air temperature can be raised within a few hours, but it may take a long time for the walls and floor to be heated once they have cooled down.
The floor temperature in the house should be approx. 30°C, when the broilers are stocked. “I ensure that the houses are kept closed as much as possible when they are empty, so I have no problem in maintaining a floor temperature of 30°C without the need for floor heating," says Leif Barsballe.
Leif Barsballe installed a temperature sensor half a meter under one of the livestock houses, which enables him to keep an eye on the floor temperature. Experience shows that the livestock house can be empty for up to two weeks without a significant drop in temperature by merely keeping the house closed.
“As a result of the broilers' genetics, feed, and management, the heat requirement in our livestock houses has changed since we built the livestock houses in the 1990s and till now”, says Leif Barsballe.
“When the first livestock houses were established near Hobro in 1992, we had a typical rotation of 48,500 broilers per house, a production time of 42 days, and a slaughter weight of 1800g. The rotation for the same house in 2019 was approx. 30,000 broilers, a production time of 34 days, and a slaughter weight of 2200g.”
“The shorter production time with increased slaughter weight has increased the need for a well-functioning heating system - even though we do not have nearly as many broilers in the livestock house,” Leif Barsballe continued.
The increased heat requirement occurs primarily because the broilers produce more moisture as a result of faster growth - a factor that is best regulated by increased ventilation and heat. Temperature and relative humidity are crucial factors for the broilers' feed consumption, gain, stress, infection risk, etc.
The six livestock houses were initially established with 2-4 hot water air heaters in each livestock house. A centrally located boiler was used for supplying heat to the air heaters.
“The changing heat requirements, coupled with the experience that the existing system did not provide sufficient and uniform heat throughout the entire livestock house, made us decide to install SKOV's Spiraflex finned tubes in two of the houses in 2011,” Leif Barsballe elaborates.
A/S Dansk Landbrug was the first poultry farm in Denmark to install finned tubes as a heat source, and Leif Barsballe expressed some concerns regarding the heat source. His primary concern was whether the tubes could supply enough heat and were easy to clean.
“Already after the first batch, I was convinced that the finned tubes were the right choice. The heat distribution in the livestock house was much better, and cleaning was hassle-free,” Leif Barsballe continued.
Leif Barsballe used a disinfection company to test the cleanliness of the livestock house after the cleaning of the first batch of broilers, and the level was the same as it was before.
“It took less time to clean the finned tubes compared to the existing hot water air heaters, just as the quality of the litter, as well as the general productivity data, showed positive trends,” Leif Barsballe continued.
The hot water air heaters also make a certain amount of noise during use, and the broilers tend to move away from the noise. The finned tubes are silent during use, which is why this type of heat source does not affect the distribution of the animals in the livestock house.
Subsequently, Leif Barsballe decided to replace the air heaters in the other four livestock houses as well. The replacement took place between 2012 and 2013.
“The change to Spiraflex finned tubes in our six poultry houses cost around DKK 800,000 including new heating pumps. We save approximately 115,000 kW annually when all of the houses have been updated, which corresponds to around DKK 100,000 saved in electricity per year,” Leif Barsballe concluded.
The investment in Spiraflex finned tubes will be reimbursed via a reduction in the cost of electricity, and no costs have been involved with the maintenance of the system.
A/S Dansk Landbrug's investment in a new heating system was necessary for providing the right productivity and well-being for the animals. “The choice of Spiraflex heating pipes reduced our electricity bill by approximately DKK 100,000 annually, so the savings we have made on power alone made the investment an economically attractive choice.”