 So I'm standing next to four feed bins these four bins take care of the pigs the feed Requirements for the pigs in the two rooms in the single building that is over Off off of the video you can see there's two flexible augers They pull the feed from each hopper bring it into the feed lines within the structure And then it's distributed with more augers all the way down the whole length of the building So the feed is probably the largest single cost that most contract swine growers encounter It's very important for them to control temperatures within the structure within the thermonutrile zone for pigs So that they don't waste feed if it's too cold inside the pigs are going to eat much more feed than they need Why just to generate heat to stay warm if it's too hot inside they're not going to eat enough They're not going to grow it's going to take much longer to market Studies show that there could be as much as an additional month of Production required if temperatures hot temperatures can't be controlled in a building like this There's very little difference between winter and summer on the inside of the building Because of the environmental control system and the ventilation systems design and management's operation of that What is that with the temperature? Feed costs are so high that it's important to maintain a uniform temperature in the building if the temperature in the building is too low The pigs are going to eat more to maintain their body temperature Just like people are going to do if the temperature is too high in the building the pigs are going to lose their appetite They're not going to eat and they're going to take longer sometimes much longer Before they're at market weight studies show that it can be as much as 30 or 40 days longer in old production systems with poor indoor temperature control in a modern facility like we have here the feed conversion efficiency is is Optimized so and the way it's optimized is by controlling the temperature because we have a modern ventilation system with very good environment control and Managers that understand how to maintain and operate the system So if we talk a little bit about efficiency in a production system like this, what's efficiency? Well, it's maximizing the output for the minimum amount of input. So on a ventilation fan. That's called ventilation efficiency It's how many CFM of airflow per watt of energy electricity that's used to drive the fan when it comes to the pork production system The primary metric is feed conversion efficiency How many kilograms or pounds of feed are used for every kilogram or pound of meat that's produced? Temperature is the critical criteria that the that controls a pig's appetite If the temperature is cold the pig eats more that means they're eating much more feed But they're still producing roughly the same number of pounds of meat So your cost just got much higher the efficiency went down same thing on high temperature if the temperature is very hot They're just not eating very much feed conversion efficiency in that case is actually usually very good However, they're taking forever to grow enough to go to market And so they're spending much more time in the building which reduces the systems overall productivity and efficiency So you can see here right now the curtain the tunnel curtain is dropping down a little bit That's because it's probably at least one more fan came on. Why is it opening to maintain a Uniform velocity of air going in somewhere between 600 feet per minute and a thousand and when I put my fan My hand in front of this I can really feel the air flow And you've already got the information on calibrated fingers and hot wire anemometers You can see this is really moving now So the system is is changing over to a temperature control mode and it's going to bring in a lot more air And it's interesting he's got a little problem here It's hanging so what we have here is the tunnel curtain now It's opened more than when we first arrived But when I put my hand over it, I can still feel a substantial velocity of air over my hand going into the building It's designed to be always operating operating at about 600,000 feet per minute And that promotes good mixing of the air into the room to make a nice vortex And then it's pulled down the whole length of the building by the ventilation fans All right, so the main idea for ventilation is that we want to provide fresh air to the animals We want to remove odor dust various toxic gases and The trick to doing that when we have high ventilation rates such as internal ventilation mode It's relatively straightforward. We open up one end of the building We turn on most or all of the fans at the other end and a lot of fresh air much much more air than is necessary To remove the pollutants comes into the building But we have all that air in tunnel ventilation Specifically to remove body heat from the animals to try to make them feel an effective temperature Which is lower than the actual temperature of the air Just like when you get step out of a shower and you're wet and there's a fan blowing you're going to feel a chill It's the same basic idea. We don't want to chill the pigs, but we want them to be comfortable However, when we're not in tunnel ventilation mode when we're just in a lower ventilation rate mode We typically call that cross ventilation or in this case at this swine facility It's it's generated by sealing inlets So the air enters through the soffits goes up into the attic and then by the number of fans that are running Which create a vacuum it pulls it from the attic down through those air inlets where we saw the smoke coming out and Distributes it into the building. We want to have enough inlets and we want them sized properly so that we get good Distribution the distribution is important so that all the animals get fresh air and that all of the spaces Have fresh air to remove the toxic or the stale air that's already in there So where you saw the smoke coming out of the inlet going along the ceiling and then coming down so That the air comes in through the attic inlets and you can see the smoke is showing you how the air is flowing It's flowing along the ceiling it hits an adjacent Jet of air coming from the next inlet they meet in the middle and then it's forcing down So that's a really nice example of properly configured attic air inlet Promoting good mixing throughout the entire building You can only see it in this one inlet because this is where we have the smoke But actually this is what's happening in all of the spaces the big challenge in ventilation is normally we can't see this air Flow so either we have to measure it with a hot wire anemometer Feel it with our skin or in this case run a smoke test to verify that everything's functioning properly That was great. Do I just do it? I don't know if I can but I can try So where do you want to start all the way at the beginning or just on the cross ventilation? Cross ventilation, okay So at lower ventilation rates when we're not in tunnel mode The system operates a little bit differently the air isn't brought in through the tunnel curtains But rather it's brought in through attic air inlets So the air enters through the soffits Goes up into the attic and then the vacuum from the fans pulls it through the inlets if the inlets are Operating properly as you see here with the smoke blasting along the ceiling that's promoting a good Ceiling jet that smoke is showing you how the jets behaving when it goes to the center towards Towards the other attic inlet it drops down That's because the jet from the other inlet and this jet are meeting and it's forcing it down So that nice roll that vortex is the basis for good interior air mixing What it's doing is putting that fresh air right down where it needs to go but first giving it time to stay along the ceiling and Modify its temperature so that the pigs aren't either too cold or too hot and it's replacing all the stale air Where you see that smoke going with nice fresh new air