Tower Silos - Better Silage - Best Savings


While the initial cost of the tower silo may exceed that of a horizontal option, in the long run the cost of spoiled forage will quickly overcome this difference. “Once waste is figured into the equation, silos can be a good investment for a farmer in the right situation” says Richard Muck, an ag engineer with the USDA’s Agricultural Research Service (ARS) dairy forage research center in Madison, WI (article posted July 5th, 2012 by Gene Lucht of “Iowa Farmer Today”)

Click Here to see entire article.

Please Click Here to see a chart comparing both Horizontal and Vertical Storage, including unloading cost, for a twenty year period. Note: The numbers shown in this cart are currently being updated.

Cost Comparisons:

Long Term Forage Storage Costs

Initial Cost

The initial cost of any storage unit is a very small piece of the total cost picture. The other costs of ownership need to be considered. That being said, generally speaking, the tower silo carries the largest upfront capital investment.

The capitol costs of the horizontal methods can be highly variable. It depends on a number of factors including, but not limited to, machinery choices, layout design, bunker wall height, and choosing to buy or rent equipment.

It is essential to realize that the cost of the storage structure is less than 20% of the total cost of ownership. Other factors such as feed loss, unloading costs, and filling costs make up the remaining 80% of storage costs.

Feed Loss

This is an area where huge costs can go unnoticed. The average bunker silo or pile will lose 17% of its’ dry matter during the storage period1. In a 1000-ton unit with a feed value of $35/ton, 17% loss comes to $6,800/year. Jim Barmore an agri-business consultant from Wisconsin made this comment, “I would suggest that, 90 to 100 percent of the time, I could help producers make more money by dealing with feed shrink than by reducing their ration cost.”

According to a study at the University of Wisconsin-Madison, the average silage bag will lose approximately 10% of its’ dry matter2. Again, these dry matter losses make storing feed expensive.

The tower silo will lose between 6% and 9% of its’ dry matter3. This is primarily due to anaerobic respiration of the fermenting bacteria.

Recognize your dry matter losses and minimize them by using the method with as little dry matter loss as possible. When using bunkers or piles, cover them with plastic and weigh it down properly. Packing bunkers and piles properly is also essential.

Unloading Cost

This is a source of major cost that most people do not realize. Operating costs on a tractor can be anywhere from $8-$50/hour4. If an hour a day is spent unloading from a bunker, pile or bags with a $15/hour tractor, the yearly cost of unloading is $5,475.00

Operating costs on a 10-horsepower electric motor to run a silo unloader is approximately $.50/hour5. New equipment for tower silos has them unloading at or above the speeds of horizontal methods. Running this unloader for one hour per day for a year costs $182.50. This is a significant savings over operating a tractor or skid steer.

NOTE: In addition to a cost savings with a Tower Silo, you can unload your feed with the touch of a button and avoid the pain of packing and covering a bunker. If you are considering a “Feed Automation” program in the future, Tower Silos should definitely be part of the plan.

Filling Costs

Filling costs is also a factor in the total ownership costs of any storage unit. It must be remembered that operating a tractor is very expensive and that the filling machines required for tower silos and silage bags wear out quickly.

The cost of buying a bagger can range anywhere from $20,000 to $70,000 depending upon size, capacity and model. These machines wear quickly. The bag must then be purchased at a price of $300 to $500. ++ Bags can also be custom filled for $800 to $1,000.++

Filling a tower silo requires a forage blower. This cost is usually quite low, $6000 to $10,000.++ However, with heavy use a blower may only last 6 to 7 years.

Filling a bunker requires only the use of packing tractors. However, large tractors are often required. These are the tractors that can cost $50/hour ++ to operate.

With proper technique, all storage methods can be filled at approximately the same speed of 100 tons/hour.


The following are approximate costs for each type of silo to be used in the following spreadsheets. For exact costs, contact your local silo construction company.

This spreadsheet compares and tally’s the cost involved in tower and bunker storage. Spreadsheet is in Microsoft Excel format. Click here to view In addition, the International Silo Association has available on request a form that, when completed, will give you a complete analysis of your feed storage situation.

Source Material

1) Brian J. Holmes, Richard E. Muck; Factors Affecting Bunker Silo Densities, April 12, 1999 and Kurt A. Ruppel, Effect of Bunker Silo Management on Hay Crop Nutrient Management, 1992

2) Richard Muck, Brian Holmes, Silo Bag Performance, June 2001

3) Howard Larson, Dry Matter Retention in Silage Storage Units; 1983

4) William Lazarus, Minnesota Farm Machinery Economic Cost Estimates; 2000

5) Calculated on an average cost of electricity over 3 months.