TABLE OF CONTENTS

City & Buildings
Public Buildings: Airports, hospitals, universities,
government and historic buildings,
hotels, and shopping malls
NH 3
: Large ammonia chillers are now safely used in heating
and cooling applications in populated areas, providing
high efficiencies and reducing energy consumption.
For example Terminal 5 at London’s Heathrow Airport
uses a central ammonia chilling plant to provide comfort
heating and cooling for passengers and workers. The
energy center for the London Olympics (2012) features
ammonia chillers as part of the low carbon heating and
cooling system that will cater for the needs across the
site. Moreover, the Aquatics Center makes use of a separate
NH 3
chillers. On the other side of the world, New
Zealand’s Christchurch airport employs ammonia chillers
to cool a freight hub, allowing temporary storage of
shipments. Ammonia chillers are also used in London
Homerton Hospital in Hackney, the world-famous UK
Children’s hospital Great Ormond St, and the University
Hospital in Akerhus, Norway, where chillers cater for the
cooling needs of its operating theatre, maternity and intensive
care units. Middlesex University uses an ammonia
slurry ice thermal storage system to provide cooling
for the whole university. To ensure safety, such systems
include a minimal refrigerant volume through plate heat
exchangers, separate sealed compartments, leak detection
systems, ammonia scrubbers and electrical switching
outside the compartments. With regards to tropical
countries, in Mauritius two government buildings had
their CFC-12 and CFC-11 chillers replaced with open
screw ammonia chillers, helping to save 1560 tons CO 2
/
year.
HC: Also now used to provide comfort heating and cooling
in public buildings are hydrocarbon chillers, which
tend to have lower capital costs than ammonia chillers,
as they do no need to use “industrial grade” steel components.
They have proven safe to install in populated areas,
in hospitals and even historical buildings. Prominent
installations in the UK include a 600 kW air-cooled water
chiller using R290 (propane) installed in the historic
Church House Westminster Abbey in London, UK, whilst
the UK Department of Transport have installed 3 hydrocarbon
rooftop chillers on Great Minster House, central
London. Arhus University Hospital Skejby, Denmark has
installed R600a (isobutane) heat pumps and R290 (propane)
chillers for comfort heating and cooling and hot
water. One estimation amounts to a global market potential
for HC chillers of $4 billion. A plan for industrial
scale production of HC chillers has been put into action
by one large supplier, which will be followed shortly by
R290 heat pumps. This should further reduce the costs
of these technologies, and increase their uptake. In addition
to their use in chillers hydrocarbons can be used in
ground source heat pumps (GSHP), as is the case in Buntingsdale
Infant Shool in the UK, where heat is extracted
from the ground and upgraded to a useful temperature
by an R290 (propane) heat pump unit.
CO 2
: Hot water heat pumps using CO 2
are used primarily
in Japan in public buildings, where for example a commercial
size Eco Cute is installed in ASA Hospital in Hiroshima,
providing 60% of the hot water demand. Such
systems are, however, now starting to appear in other
countries. In Ireland and the UK the Cúil Dídin Nursing
Care Facility and Beechdale Manor Care home both use
CO 2
heat pumps to provide all their hot water needs.
The name of the Eco Cute comes from the Japanese
phrase Shizen Reibai Hīto Ponpu Kyūtō-ki, which literally
means “natural refrigerant heat pump water heater”. Eco
is a contraction of either Ecology or Economical and Cute
is a near homonym to kyūtō ; literally “supply hot water.”
Commercial buildings: Air-conditioning
& Heating
NH 3
/ HC: In the last decade ammonia and hydrocarbon
chillers have started to gain acceptance for the provision
of comfort air conditioning (A/C) and heating for universities,
hospitals, hotels, office buildings, convention
centers, and airports. In Asia, several hydrocarbon chiller
conversions have been undertaken in the Philippines, in
Gaisano Country Mall, Legenda Hotel and the Mandarin
restaurant. The Jusco Melaka shopping centre in Malaysia
has also converted its cooling system to hydrocarbons,
installing 50 25-50 kW water-cooled packages and
100 split systems. In Indonesia, the Grand Melia Hotel,
Jakarta, retrofitted six chillers with R290 (propane) to
provide air conditioning. Unfortunately, due to a lack of
trained technicians this retrofit was recently re-retrofitted
back to R22. In addition hydrocarbon ground source
heat and exhaust air heat pumps have been developed
in Europe, where they have been installed to provide
heating to schools and residential buildings. These can
also be installed in commercial buildings.
CO 2
: In South-West Japan a business hotel in Tottori uses
a commercial Eco Cute heat pump water heater, whilst
O’Donovan’s Hotel in Ireland has also invested in a CO 2
heat pump water heater after seeking an efficient and
renewable alternative to their hybrid solar-oil fired boiler
system.
Data Centre Cooling
CO 2
/ HC: Data centres that house computer systems and
components such as telecommunications and storage
systems need to have rigorous temperature and humidity
control to maintain the server components within
the manufacturer’s specified range. Recently CO 2
, which
poses no danger to electrical equipment and is more efficient
than air or water, has been used as the refrigerant
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