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The technology in ice storage has grown immensely over the last few years and today even the ice building process can be managed to maximise output through simple techniques such as flow control in refrigerant and heat transfer water circuits .
Intramech
HOW ICE STORAGE BENEFITS A BUILDING OR PROCESS REQUIRING COOLING The main objective in using ice thermal storage as you have no doubt worked out by now is to shift cooling needs in part , or in full by banking energy , through either of a number of solutions , at a cheaper rate and to reduce peak demand charges and grid pressure . It is likened to the same principle as charging a battery for use as required at a later stage .
Many HVACR designs today , in the drive towards efficiency and ‘ greening ’ solutions take into account entire lifetime sustainability factors which include capital expenditure , operational costs and environmental impact ( or carbon footprint ).
A common yardstick for the client is the payback period of their investment . This factor is really ' as long as a piece of string ' to work with , as the well-known saying goes , but for the purpose of illustrating the value associated to ice storage , a typical installation without ice storage that would have a payback period of 8 years ( which can be perceived as long ) can be modified to reduce the payback period to as little as three years by including ice storage – which now becomes very appealing .
“ Ice storage is an excellent and very relevant technology system and will be more so in future , not only because of the obvious ability to save energy ( and money ) but also because it can be applied very flexibly in a large range of applications . It has also been proven that through the correct design processes , there is an opportunity to gain the lowest first cost chilled
Here an internal tank view of the ice ball system . This method freezes the balls rather than around the coils and a glycol solution is circulated through the tank .
Evapco Evapco
Here district cooling ice tank is being completed .
Ice storage comes in a variety of sizes and can suit a number of applications .
system versus a standard chilled water system ”, says Andre van der Merwe , managing director at Evapco South Africa .
Inclusion of ice storage in a system further enables a reduction in all of the component sizing . Reducing sizes does not only save on the cost of the equipment itself that can be proportionally reduced , there are often savings on the installation cost too . Further to this , there are direct impacts on connected or related components . These include things like the electrical distribution , wiring , starters , transformers , and so on . These are beneficial impacts on both electrical and mechanical savings that can be transferred to the client .
In the past , thermal storage for cooling was achieved by using large tanks of cold water , but with the shift to ice , further benefits are possible such as greatly reduced footprints ( ice systems require about one tenth of the volume required with water ), more suitable temperature differentials , and an extended period of cooling supply ( dependent on setup of course ).
Effectively , with the inclusion of ice storage and creative design , you can supply chilled water to a building or process ( for a limited time ) merely with a couple of pumps which makes the
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