World marine refrigeration is beset with three problems at present:

• High Consumption of Energy
   
  If install a fridge in fishing boat, especially the combination of fridge and freezer, the energy needed is a knotty problem. A fridge operating under 12 voltage with electric current intensity 150A, consumes electricity 1850 w which about equal to the energy provided by two 80 batteries when they are working rightly. Therefore, if we put fridge in fishing boat, there will come out the problem of inadequacy of energy sources, unless we adopt another way. Freezer will consume more electricity than fridge, then require much more about energy sources.
   
• Availability of Energy sources 
   
  Special environment that marine refrigeration system placed in decides its special requirements for source of energy. Because such system is installed in ship and has no fixed place, it can not get the continuous supply of energy source. It only can not get the continuous supply of energy source but obtain from local source, battery and some energy-storing equipment.
   
• Space Requirement of Equipment
   
  The stability on seas is much less than that o9f in lands, and it is so inconvenient for the refrigeration equipment to work with security and stability. It may be made as the fashionable “ changeable box” system with various components, then inlaid with refrigeration system, however, it is not a method of taking both radical and stopgap measures. Meanwhile, some refrigeration equipment occupies large spaces of ships because of their enormous volume, and this will affect the loading quantity of ships.

DY fishing vessel diesel engine exhaust icemaker is especially designed for those fishing vessels with horsepower above 100 and tonnage below 100t. It rewrites the history that fishers has gone fishing on the sea carrying a lot of ice over the past one hundred years and contribute a lot to world marine refrigeration: 

1. DY technology has no need of electricity; it attains to refrigeration by utilizing heat energy (exhaust of diesel engine, surplus heat, evaporator or waste water with the temperature above 110℃) without any increase of oil consumption. 

2. It can design according to the particular condition of vessels no matter they have small tonnage or large tonnage, and provide the good service of refrigeration and cold preservation.

On the basis of saving energy, it thereof has solved the problems about the high consumption of energy and the availability of energy source. Simultaneously, DY products ask for no special foundation for installation, are of safety, and are not affected by pitch. You can set up them simply, easily and safely. 

When DY heat energy adsorption technology is applied to marine refrigeration, its distinctive virtues assure that its marine refrigeration products will touch off a revolution in circle of marine refrigeration. The fruits of this application are DY fishing vessel diesel engine exhaust icemaker and DY fishing boat exhaust refrigerator, which open a new page of the production and life of the fishers. 

Brief introduction is respectively presented infra.

Contrast between Utilization of DY Icemaker and Other Methods for Keeping Freshness of Aquatic Products

Compared with carrying ice to go fishing

It is well known that the fishing vessels with the tonnage below 100 T can not bring compressive icemaker to go fishing on the sea because of their small horsepower. So carrying ice to go fishing is the only way to preserve aquatic products. But this way has its inevitable disadvantages:

1. It wastes too much that carries ice to go fishing on the sea, because the spoilage rate of ice amounts to 50%.
    
2. Ice needed for preservation is in large quantity, which occupies large space of ships, and affects the output of fishing and the load capacity of ships.
    
3. Such traditional ice-making factories may not exist at every fishing port. Taking Wuqi Harbor of Taiwan as the example, fishers must reside in inland for purchase of ice in convenience and pay for processing and transporting. Moreover they need to go to and fro between fishing area and fishing port every three or four days to buy ice and pay for transportation. So the cost is high.

While using DY icemaker to attain to refrigeration can avoid the problems above. It achieves refrigeration only with exhaust of diesel engine, and also has the merits of energy saving and environment protection. We will take Chenggong Port of Taidong County as the instance, which is a small port having 200 fishing boats and all of them are not be equipped with refrigeration systems. Fishers there all go fishing with a lot of ice. Neglecting the expenses on going to and fro between fishing area and fishing port as well as ice transportation, only taking the cost of ice-manufacturing into account:

• Unit of ice: Piece 
• Weight of ice: 100 kg~120 kg/piece
• Value of ice: 200 NT/piece
• Ice needed for going fishing every time: 80~200 pieces
• Periodical requirements for ice: every five to eight days

As the statistics above show, it is obviously that fishers will expense 800,000 NT at least and 2,000,000 NT on buying ice. If the exhaust of diesel engine in boat can be made full use of to get refrigeration, DY icemaker can produce about 10t-flake ice (seven days calculated in according to 50% of workload), which completely satisfies fishers wants and needs. It is more important that DY icemaker has hardly any need of maintenance and repair, and has nearly 20 years service lives. If the expenditure on purchase of ice every year of the whole fishing port can be saved, it will be an astronomical figure when it is accumulated 20 years! Then a conclusion can be undoubtedly draw that DY icemaker will greatly increase the economic senses of fishers. 

Compared with compressive icemaker 

Although compressive refrigeration system is the most popular one at present with absolute superiority in market, it also has some disadvantages listed as below, which can not be neglected:

1. The cost for manufacturing is high (nearly 800,000 NT).
    
2. It is flooded with noise.
    
3. Regular maintenance for system is needed. Furthermore the cost is not low. For instance, there are about 2,000 medium-sized or large fishing vessels at East Harbor. Most of them have been installed with refrigerated preservation equipment for strengthening the effectiveness of freshening. The cost is near 50,000 NT every time. 

While DY icemaker has the incomparable virtues:

1. There is no noise during its operation. Even when your are sleeping it still runs quietly.
    
2. Because the system almost has no motion parts, it needs little maintenance and save a sum of expenditure on regular repair and maintenance.
    
3. When the system dose not work, there is no liquefied ammonia with high pressure. So it is of higher security.
    
4. Its service life can nearly reach to 20 years. You only need pay for it once and benefit from it all your life.