We round up the key facts you need to know about the reefer shipping industry, including developments over time, the top manufacturers, and where the sector is heading next.
The term 'reefer' is used in shipping to refer to refrigerated ships and refrigerated shipping containers that transport perishable commodities by sea.
Temperature-controlled transportation is used for perishables such as fruit, meat, fish, vegetables, and dairy products.
A reefer ship is a containership that exclusively carries refrigerated containers.
However, reefer ships were the predominant mode of transporting goods in controlled conditions before the advent of reefer containers.
Reefer ships differ from conventional container ships in their size, design, power generation and electrical distribution equipment.
The key difference is that they are smaller and require provisions made for powering each container's cooling system.
Refrigerated containership Ivar Reefer in the Port of Valparaiso, Chile
Reefer ships are generally side-door vessels which have water-tight ports on the ship's hull that open into a cargo hold.
Inside these access ports or side doors, pallet lifts or another series of conveyors bring the cargo to the respective decks.
This special design makes the vessels particularly well suited for inclement weather operations as the tops of the cargo holds are always closed against rain and sun.
Inside reefer ships food and other perishable items sit on pallets in a refrigerated hold, and are delivered to a cold storage facility on arrival at a port.
Reefer containers, in white, stacked with normal dry containers
Reefer containers are, simply put, large fridges carried by containerships.
Each container has its own individual refrigerated unit.
These containers are nearly always twenty-foot equivalent units (TEUs) — the standard size for cargo containers loaded by containerships.
The additional insulation and the power plant results in a 40-foot reefer costing around six times more than a regular container.
Because reefer containers are self-contained refrigerated units, they are often able to bypass cold storage on arrival at a destination.
And, because of the ease in loading and unloading cargo, many containerships are now being built or redesigned to carry refrigerated containers.
The M.V Victoria, a 13,400-ton Italian motor ship designed to run from Italy to Egypt becomes the first vessel to make its maiden voyage equipped with Carrier cooling systems. Image credit: Carrier
Top Industry Developments:
First refrigerated marine containers came into use based upon converted truck units
Maersk Line received the first reefers with integrated cooling units
In 2013, 72% of the refrigerated transport capacity in maritime shipping was containerised, growth from 33% in 1980.
The share of the conventional or specialist reefer segment fell from 60% in 2000 to an estimated 26% in 2014.
This reflects the core trend of the last few years: the refrigerated box taking over from the conventional reefer ship. This has resulted in more than half of all conventional reefer vessels scrapped since 2000.
Seaborne transport of fresh produce in conventional reefer ships and in refrigerated boxes is estimated to have reached more than 95.7 million tonnes.
However, the maritime transport of fresh produce only accounts for 2.7% of the world seaborne trade of dry cargoes of all kinds.
Future growth for the seaborne perishable trade predicted to expand by 4% to 5% annually until 2020.
Top reefer box and machine manufacturing companies:
Image credit: Carrier
A subsidiary of Carrier Corporation, which was founded 1903.
Willis Carrier, founder of Carrier, invented the first air conditioner in 1902.
The M.V. Victoria, a 13,400-tonne Italian motorship designed to run from Italy to Egypt, becomes the first vessel to make its maiden voyage equipped with Carrier air conditioning in 1931
Carrier Transicold introduces the first natural refrigerant container unit in 2010, incorporated in the NaturaLINE unit.
The unit incorporates carbon dioxide (CO2) in place of conventional synthetic hydrofluorocarbon refrigerants, which have higher global warming potential (GWP).
Container units include: NaturaLINE, PrimeLINE, ThinLINE, EliteLINE.
Maersk Container Industry (MCI)
Reefer manufacturing subsidiary of A.P. Møller-Mærsk A/S
Engages in the development, manufacture, and supply of dry containers, reefer containers, and refrigeration machines
Leader in low energy consumption reefer units which reduces operational costs and environmental impact
Products include: Star Cool, Star Cool Integrated, and MCI Box
Diversified container fleet of approximately 2.3 million TEU
Depot network in more than 176 port locations, across 49 countries
Owned by Bermuda-based Global Sea Containers Ltd.
Products include: 20 foot Standard and 40 foot High Cube
Offer a variety of transport refrigeration and freezer containers, including: Dual Reefer Systems, Explosion-Proof Reefers, Tank Container Reefers, Offshore Reefers, Blast Freezers, Deep Storage Freezers, Quick Thaw Containers, Expandable Containers, DNV Refrigerated Containers
Daikin Active CA is helping both growers and shipping lines access new markets and expand business opportunities.
Japanese-based Daikin Transportation and Refrigeration Systems Division is a wholly owned division of Daikin Industries
Daikin Industries annual sales in excess of US$ 12 Billion
Largest global supplier of container refrigeration machines using scroll compressor technology
Supplies equipment to over 50 liner shipping and leasing companies
Products include:Daikin Active CA, LXE Series, Zestia Series
BSL Offshore Containers
Based in Hong Kong
Products include: ISO Reefer, ISO Storage Reefer, Chiller/Freezer Cold Storage Reefer, Specialty Reefer containers and DNV reefers
Changes in refrigerants and regulation
Typically a reefer will have an integral refrigeration unit that will rely on external power from electrical power points (reefer points) at a land-based site, a container ship or on a quay.
Generally, air cooling systems are used that remove heat generated by the reefers.
Water cooling systems are also used. This system can be used if the reefer is stored below deck on a vessel without adequate ventilation to remove the heat generated.
Another refrigeration system is sometimes used when the journey time is short or during a period when there is a total loss refrigeration.
This involves the use of frozen carbon dioxide ice or sometimes liquid nitrogen for cooling.
The cryogenically frozen gas slowly evaporates and cools the container and is vented from it.
Full-size intermodal containers equipped with cryogenic systems can maintain their temperature for the 30 days needed for sea transport.
Recent years have seen various new technologies released by shipping container manufacturers to better address the cooling requirements of specific cargo.
There has been a particular focus on controlled atmosphere (CA) technology.
This active oxygen removal system delays the ripening, ageing and decay of perishables to preserve their quality, taste and value during long-distance transportation.
Many innovations in areas such as energy efficiency are occurring as the result of increased regulation.
HFC refrigerants in particular have been identified as a major contributor to global warming.
Movement towards more environmentally sustainable refrigerants is rapidly gaining pace within the container reefer industry.
In 2015, European Union’s F-Gas regulation set out a timetable to cut the amount of CO2 contributing to global warming by 2030 by half.
Bans have also been proposed by the US Environmental Protection Agency’s Significant New Alternatives Policy.
Produce reefers carry and challenges presented
Fruit and meat have historically been the main cargo of refrigerated ships.
Bananas represent the single most important reefer cargo.
Cargoes of shrimp, asparagus, caviar and blood are considered among the most expensive refrigerated items.
Other cargo includes dairy products, flowers and pharmaceuticals.
Because the characteristics of reefer cargo vary from commodity to commodity, factors such as temperature control, air exchange, humidity levels and proper packing and stuffing become extremely important.
For example, cargoes such as meat have to be kept chilled between 0 degrees and minus 2 degrees, or frozen at minus 18 degrees or colder.
Other cargoes such as fresh fruit have to be kept at temperatures ranging from minus 3 degrees celsius to 16 degrees celsius to ensure they arrive in the best possible condition.
Specific goods also present challenges for transportation
For example, some products such as tomatoes and potatoes require changes in temperature throughout the voyage.
Containers now use pre-programmed multi-temperature systems.
Other products, such as fruits and vegetables, require a reduced level of humidity.
Many containers can regulate humidity between 55% and 95%.
Normal carrier lines: taking away trade
Reefer containers are rapidly gaining market share and are competing with reefer ships for trade.
Traditional systems built around reefer ships involve food sitting on pallets in a refrigerated hold; delivered to a cold storage facility on arrival.
This is rapidly changing to containers with refrigeration units. This new generation of container ships with a large reefer capacity is transforming how fruit, meat and other perishable foods move around the globe.
At the beginning of 2000 there were over 20 companies worldwide who were specialised in transport with reefers. Now there are only eight.
A key reason behind this change is that diversified carriers that have the capacity to hold reefer containers offer a faster return on investment as well as the fact that they give carriers greater security in an unstable market.
Every dollar a carrier puts into a bulk carrier is made back in two years on average.
However, for reefers, it can often take 20 years to earn it back.