| Thermal Energy Storage (TES) may be considered as | | | | very attractive lower cost to install and run. |
| a useful tool to reduce the cooling load requirement | | | | These passive cooling units can be supplemented |
| by means of spreading day time loads over 24 hour | | | | using a very small refrigeration compressor or a |
| period utilising the naturally occurring ambient | | | | chilled water circuit for lower temperatures but |
| temperature difference. | | | | products like chocolate, bakery products and flowers |
| The night-time cooler ambient can be used to charge | | | | can be easily maintained under control by simply |
| the latent heat capacity of various Positive | | | | charging these beams / containers over-night and |
| Temperature Eutectic also called Phase Change | | | | utilising the stored energy during day-time transport. |
| Material (PCM) solutions between +4°C ( 39°F) | | | | Furthermore, this concept enables the owners utilise |
| and +117 °C (243°F) without using any | | | | their standard Lorries to be used as refrigerated |
| refrigeration machinery by simply allowing the | | | | trucks during harvest / peak season at a fraction of |
| surrounding air to freeze these solutions. Later the | | | | the cost for a conventional refrigerated truck. |
| stored energy by the Positive Eutectic, PCM Thermal | | | | HVAC / Air Conditioning PCM passive cooling concept |
| Energy Storage can be released back to the | | | | offers mechanical refrigeration free passive-cooling by |
| occupied space during day-time to handle the heat | | | | simply storing the night cool energy and releasing the |
| gains. | | | | stored cold latent heat capacity during day-time to |
| This technique is generally called Passive Cooling and | | | | keep the space temperatures under control. Low |
| it may enable the charging process to take place by | | | | ambient temperatures coupled with free cooling offer |
| means of free cooling, i.e. without running the chillers | | | | a significant reduction of energy consumption relating |
| and as a result becomes a very economical and | | | | to the cooling operation, which is in the region of |
| environmentally friendly system. Furthermore, PCM | | | | 16-46 % depending on the type of passive cooling |
| energy storage opens new opportunities to explore | | | | unit and location. |
| heat balance for the existing and new systems, | | | | Based on the applied projects, ambient profiles in |
| which could offer significant overall system efficiency | | | | many parts of the world and associated feasibility |
| improvements. | | | | studies indicates that PCM assisted Passive Cooling |
| Alternatively, the sun energy during day-time is | | | | concept offers economical and very environmentally |
| stored and later utilised during colder night-time to | | | | friendly cooling options. In any country whereby the |
| heat the space for a free heating as well as storing | | | | night ambient does not allow being sufficiently low |
| heat in the hot water circuits. | | | | enough to charge PCM Thermal Energy Storage |
| Privatisation has created a new kind of energy | | | | (TES) cells over-night, a supplementary dry cooler |
| market whereby the period of energy usage and the | | | | and / or small chiller can be added to top up the |
| type of energy used is becoming the main criteria for | | | | difference between the ambient and PCM |
| price structuring rather than overall energy | | | | temperature for an economical solution. |
| consumption. Hence, cooling systems must be | | | | Modern society’s reliance on refrigeration and air |
| designed to provide sufficient flexibility for load | | | | conditioning indicates that refrigeration and the |
| shifting and a PCM Thermal Energy Storage technique | | | | associated environmental issues will be with us for a |
| can be considered as a useful tool to achieve this | | | | considerable time and therefore one has to utilise |
| aim. | | | | existing and available alternative technologies with |
| Building services must be designed to provide | | | | minimum usage of energy. |
| sufficient flexibility for load shifting and energy usage | | | | A Positive Temperature Eutectic “ PETES “ |
| control in order to achieve the most economical | | | | Thermal Energy Storage not only provides the end |
| operation. A PCM Thermal Energy Storage technique | | | | user with an Environmentally Friendly design but also |
| whereby "Storing High or Low Temperature energy | | | | the following additional benefits can be obtained: |
| for later use in order to bridge the time gap between | | | | • Reduced and No Refrigeration Equipment |
| energy availability and energy use" can be considered | | | | • Capital Cost Saving |
| as a useful tool to achieve this aim. | | | | • Reduced Maintenance. |
| Passive Cooling PCM Thermal Energy Storage (TES) | | | | • Energy Cost Saving |
| benefits can also be applied for electronic chamber, | | | | • Reduced CO2 Emission |
| shelter, telecom shelters, remote pump and electric | | | | • Environmentally Friendly Installation |
| control cabinet cooling for remote location whereby | | | | • Improved System Operation / Reliability |
| the lack of electricity eliminated the mechanical air | | | | • Flexibility for the Future Capacities Changes |
| conditioning or alternatively mechanical cooling free | | | | The temperature ranges offered by the proposed |
| applications around the World. | | | | Phase Change Materials solutions utilise free ambient |
| These Passive Shelter Cooling systems can even | | | | cooling, conventional chilled water temperature ranges |
| operate in hot countries like the Middle East due to | | | | for both the charging and discharging sides of the |
| higher space temperature (45ºC / 113°F) | | | | system. Hence, they can be applied to any new or |
| requirements in comparison with Office Cooling. A | | | | retrofit application with minimal technical and |
| PCM solution of 32ºC (89.6°F) is sufficient to | | | | economical impacts. |
| maintain the room temperature below 45°C | | | | Finally, the possibility of Free Cooling Cycle TES |
| (113°F) by simply using the temperature swing | | | | system offer new horizons for designers to control |
| between day and night time. | | | | the energy balance to match the load and electricity |
| The same concept has also been successfully applied | | | | demand / consumption of the system as a whole. |
| for cold storage transport applications using Eutectic | | | | Zafer Ure, M.Sc., C.Eng., MCIBSE., MASHRAE., MInstR., |
| beams. The majority of the perishable food must be | | | | is the Managing Director of Environmental Process |
| chilled during transport but the cost of refrigerated | | | | Systems Ltd. and has 25 years experience in the |
| truck restricts the use of transport cooling in | | | | HVAC industry and has writen many papers for |
| particular in the third world where the biggest waste | | | | industry conferences and magazines. Details of PCM |
| occurs. A PCM, Eutectic filled high ceiling beams can | | | | Products can be found ay and Zafer can be |
| be simply charged using standard cold storage can | | | | contacted on +44 1733 243400 or at z.ure@epsltd.co. |
| keep the product temperature under control at a | | | | |