The use of silos for storage has become increasingly common. Grain silos have been in use on farms for many years but more recently on-farm storage silos for fertiliser products have become more popular.
Both leading fertiliser companies in New Zealand promote the use of fertiliser silos mainly for storing urea. Such on-farm urea storage offers convenience to the farmer allowing access to the product on an as-needed basis. Common on-farm silos supplied through Ravensdown or Ballance have a storage capacity of about 12-14 tonnes of urea, with a standard delivery quantity of about 12 tonnes.
Silos increase convenience but if used carelessly they pose a significant safely hazard.
Many silos require a person to climb the silo to replace the lid following filling. If the silo is wet this makes it even more hazardous.
There are a number of modifications that can be installed to improve safety, including permanent filler tubes that product can be blown through, installing fill indicators using clear materials at intervals up the silo, installing a lid open and closing device that can be operated from the ground and fitting a ground level hatch to allow cleaning.
