Cold room technology is often associated with industrial uses. We can picture large cold storage warehouses and all the trappings of an industrialised society. But it isn’t all this way. Quietly and unbeknown to most people cold storage is at the heart of a project which might literally save the world. Since the 1960’s Kew Gardens have been building a collection of seeds- really a seed bank which they hope will store some 25% of the world’s species by 2020. Whilst the largest collections are in the UK there are growing requirements to store the seeds “in country“..you see not every government is willing to let their precious natural resources be transferred abroad ( perhaps a sad reflection on the patenting wars associated with the GM industry)
The cold rooms which are used to store the seeds are detailed here
Details about seed banks
So what would the specific cold room requirements be?
Minus 20 degrees C as an operating temperature.
Adjacent to the drying room so that only dry air with a low moisture reading can enter the room.This will reduce the build up of ice in the cold room. It is also worth noting that drying the air within a coldroom is difficult and expensive.
Build the cold room with styrofoam panels between 100mm to 200mm thickness. The thicker the better. Obviously the set up costs will increase but these rooms are built for long term use and the running costs and stability will be much improved.
The floors should also be styrofoam but topped with plywood and a non slip steel plate.
Use an air gap or a heater mat to keep the ground from freezing. Particularly important for temperate locations.
Fully loaded seed shelves will be heavy so check the load bearing statistics for the floor or even the walls if you affix shelves.
The refrigeration equipment is usually housed in a separate location adjacent to the cold room and connected by pipework.
A small seed bank will require a coldroom of perhaps 35 cubic metres. This size is possibly more common for in country banks whilst an international seed bank might realistically require 350 cubic metres of cold room – and that is a large room!
Install a back up generator and agree maintenance contracts for the equipment.
How long should a cold room last? Well under light usage around 25 years.
Health and Safety tips
It is essential that cold room doors can be opened from the inside, even when locked. Walls should contain a pressure release valve: negative pressure can develop in the room as temperature decreases, which can make opening the door more difficult.
Staff must be issued with suitable clothing both to keep them warm and to minimise contamination.
You can see the main article here