TY - BOOK
T1 - Feasibility of cool storage systems in refrigeration
AU - ElMahgary, Yehia
AU - Kekkonen, Veikko
AU - Laitinen, Ari
AU - Pihala, Hannu
PY - 1989
Y1 - 1989
N2 - In the present report the economic viability and
technical
feasibility of selected cool storage systems
are considered. Cool storage has clear potential for
several applications: in connection with air-conditioning
systems, domestic refrigerating and freezing systems,
commercially e.g., in the dairy and
vegetable industries; and in deep freezing, as in the
meat
industry. Air-conditioning has limited significance in
Finland. For this reason it was not investigated in this
study.
In domestic refrigeration and freezing two systems were
investigated; a controlled cooling heating system and a
simple built-in system in individual refrigerators and
freezers. The central cooling/heating system in houses
was
found to be economically unattractive. It also has
several
technical drawbacks. The simple built-in system appeared
to
be promising. The amount of savings is rationally a
function of the difference between day and night tariffs
and the costs of installing an automatic switch and
storage
media. A problem with the application of cool storage in
domestic refrigerators and freezers results from the
absence of clear peak hours.
In the vegetable and dairy industries cool storage also
has
considerable potential. Several systems were investigated
in this respect and compared to the conventional system.
The cool storage system using Cristopia balls, one of the
most common commercial systems available in Europe, was
not
economical at a tariff difference of 10 p/kWh or more.
The
cost-effectiveness of the system, however, improved
considerably when an outdoor heat exchanger was added to
make use of natural low ambient temperatures. Further
improvement in the economic viability of the system was
achieved when a sub-cooling system using outdoor
temperatures was added. Still, the investment costs of
the
Cristopia system seem too high to justify the cool
storage.
A cheaper cool storage system could make the cool storage
application more attractive.
Cool storage for freezing in meat plants was also
investigated. Again, in view of the relatively high costs
of the Cristopia balls, the connection of such a cool
storage system to existing plants was economically
unattractive.
Cheaper cool storage systems may be more attractive. On
the
other hand, even the cool storage system using Cristopia
balls was found to be economically attractive when its
size
was optimised with the plant power in a new plant. When
the
net annual savings were about FIM 170 000 and the pay
back
period was about 6 years. More savings are expected from
the cheaper cool storage system than from the Cristopia
system.
AB - In the present report the economic viability and
technical
feasibility of selected cool storage systems
are considered. Cool storage has clear potential for
several applications: in connection with air-conditioning
systems, domestic refrigerating and freezing systems,
commercially e.g., in the dairy and
vegetable industries; and in deep freezing, as in the
meat
industry. Air-conditioning has limited significance in
Finland. For this reason it was not investigated in this
study.
In domestic refrigeration and freezing two systems were
investigated; a controlled cooling heating system and a
simple built-in system in individual refrigerators and
freezers. The central cooling/heating system in houses
was
found to be economically unattractive. It also has
several
technical drawbacks. The simple built-in system appeared
to
be promising. The amount of savings is rationally a
function of the difference between day and night tariffs
and the costs of installing an automatic switch and
storage
media. A problem with the application of cool storage in
domestic refrigerators and freezers results from the
absence of clear peak hours.
In the vegetable and dairy industries cool storage also
has
considerable potential. Several systems were investigated
in this respect and compared to the conventional system.
The cool storage system using Cristopia balls, one of the
most common commercial systems available in Europe, was
not
economical at a tariff difference of 10 p/kWh or more.
The
cost-effectiveness of the system, however, improved
considerably when an outdoor heat exchanger was added to
make use of natural low ambient temperatures. Further
improvement in the economic viability of the system was
achieved when a sub-cooling system using outdoor
temperatures was added. Still, the investment costs of
the
Cristopia system seem too high to justify the cool
storage.
A cheaper cool storage system could make the cool storage
application more attractive.
Cool storage for freezing in meat plants was also
investigated. Again, in view of the relatively high costs
of the Cristopia balls, the connection of such a cool
storage system to existing plants was economically
unattractive.
Cheaper cool storage systems may be more attractive. On
the
other hand, even the cool storage system using Cristopia
balls was found to be economically attractive when its
size
was optimised with the plant power in a new plant. When
the
net annual savings were about FIM 170 000 and the pay
back
period was about 6 years. More savings are expected from
the cheaper cool storage system than from the Cristopia
system.
KW - cooling systems
KW - refrigeration
KW - feasibility
M3 - Report
SN - 951-38-3253-8
T3 - Valtion teknillinen tutkimuskeskus. Tutkimuksia - Research Reports
BT - Feasibility of cool storage systems in refrigeration
PB - VTT Technical Research Centre of Finland
CY - Espoo
ER -