Solar Powered Inflator Fan Update & Alternative

We have been continuing to get many inquiries about solar powering the inflator fan for greenhouses and livestock buildings, which is used to put air between two layers of plastic roof cover. For the last year we have been experimenting with a solar collecting package to determine what is required, while we work to keep our interested customers updated along the way.

The first thing that must be emphasized, is that you MUST use a squirrel cage type of fan and not a propeller type. The propeller type can not continuously run against back pressure.

The output required will be determined by the size of the greenhouse or livestock building. Our regular 110 volt fan draws .25 amp and puts out 80 cfm. Some small buildings can use a smaller fan and some of the bigger ones require our double output fan which gives 130 cfm.

Our inflator fan works quite well going through an invertor. Any 12 or 24 volt fans which we have tried have been extremely noisy and therefore not feasible.

The biggest challenge which we encountered, is that the specific time the fan is needed the most for heat insulation, is also the time where there is the least capacity for generating power.

We used a single solar collector and a single battery and there was simply not a quick enough capacity for the battery to hold charge when we had several consecutive cloudy days in December/January

To add another solar collector to an already fairly expensive package, really becomes prohibitive and can deter from moving forward with it.

Based on this experience, we wanted to offer an alternative that balanced economy with feasibility. We have come up with a way where the extra roof plastic can be used on the inside of the structure.

This means that you would not need the inflator fan but still have the effect of double plastic with the air pocket for better heat efficiency. This system does require a bit of extra “fiddling” but the net cost will be a little less.

1. The structure is covered with a single layer of plastic just the same as you would if you were only doing a single layer.
2. Take the second piece of plastic inside the greenhouse and fold it double lengthwise.
3. This double plastic will be attached to the underside of the ridge using the same aluminum as you would use to fasten the plastic to the roll up pipe.
4. Next remove the purlins from the one side of the structure and after you have pushed over the plastic, reinstall the purlins under the plastic. You will be pushing the bolts through the plastic.
5. The plastic will be fastened with wirelock to the underside of the end hoops.

We have already had some customers try this out and are very happy with the result. Please call us with any questions or to discuss your specific application and situation where you might use this. We would be happy to help you with your project!

Winter Storm and Your Structures

Winter Storm & Your Structures

Many areas have been hit with freezing rain today and even though it has generally not been enough to warrant concern for the structures, it is a good time to recap some common things when dealing with ice on buildings.

It is important to note that the ice in itself is not an issue, even a very thick layer actually has enough strength to become self supporting. There are two potential problems though:

  • If the ice stays on the building, it usually has a rough enough texture that subsequent snow will not likely slide off. This scenario lead to major problems in previous winters when we had freezing rain, followed by a dump of snow and then we had rain. This can triple the weight on a building in very short order.
  • The other potential problem happens when you are attempting to remove the ice from the building. If the ice layer is not too significant you can gently bump the cover from the inside. ALWAYS start bumping the cover from the top. This way ice will slide over ice. Starting from the bottom creates a potential where the ice sliding down will fall back against the building and slash the cover. NEVER do all of one side and then the other. Work both sides simultaneously.

If there is the slightest doubt in your mind about the amount of weight on the building, bump the cover from the outside using something with a long handle.

If in doubt please don’t hesitate to ask.

The benefits of going to a bigger structure

What are some of the benefits of going with a bigger structure over a smaller structure?

Budget often dictates that someone needs to start small, especially when a person is just starting out as a grower with a greenhouse.
There is also the perceived notion that staying smaller means less heating cost. In itself, that is true, since heat loss is in direct proportion to surface area exposed to the outside.

As I have mentioned before, it is very important to weigh expense
against return.

A smaller air volume has less natural circulation.
Proper air circulation for plants is critical regardless of the season.
Think of a deep pond versus a shallow pond. The deep pond never has algae on the surface because of the increased movement.

Going with a taller greenhouse will automatically increase the circulation the same way.

Another point to consider with a taller greenhouse, is that there is more open space above the plants.

This open space is where moisture can go, away from the plants even before the greenhouse ventilation system does its job.

With a lower greenhouse, moisture is always in close proximity to the plants. In a taller structure, the plants will be dry much sooner.

Moist plants in a stagnant air mass are prone to disease. These plants will, as a result, produce less.

As always, be aware of the bigger picture.