and cooling systems; and second,
through adaptive occupancy scheduling.
Radiant heating is able to respond far
more quickly to changes in occupancy.
This is because instead of heating the
air within a building, it directs heat
on to the occupants, in the same way
as sunshine. Radiant heating keeps
workers comfortable while maintaining
significantly lower temperatures. The
same is true on a sunny day, when it
often feels far warmer than the actual
air temperature - until the sun goes
behind a cloud. With radiant heating, the
same system that controls lighting can
also control heating, by simply switching
it on as people enter a space.
Infrared radiant heating has long
been popular in agriculture. Heating the
air within agricultural buildings would
be extremely expensive due to a lack of
insulation and very high levels of natural
ventilation. However, heat lamps can be
easily fitted over pens holding livestock,
such as chickens or lambs, providing a
cost-effective way to keep them warm.
Gas-fired versions of such systems
provide the improved controllability and
heating efficiency of radiant heating
with the lower energy cost of natural
gas. This makes them better suited to
larger-scale heating applications.
Steve Sherman, MD of supplier
Schwank UK, says: “Gas-fired infrared
radiant heating systems, being
decentralised, offer businesses
a high degree of flexibility in how
their heating installations can be
configured. Intelligent temperature
control technology can make a positive
contribution to energy management in
industrial and commercial buildings.”
After HVAC, lighting is typically
the next largest user of energy. With
ENERGY – BUILDING MANAGEMENT SYSTEMS
modern designs of passive heating
and cooling, lighting can even become
the main energy requirement. Lighting
controls can reduce unnecessary
artificial lighting by using motion
sensors and schedules, in combination
with daylight harvesting louvres.
While smart lighting is able to turn
on and off, room by room, as occupants
move through a building, only a BMS is
able to integrate these functions with
the use of daylight harvesting, heating
and cooling.
To do this most effectively, the BMS
must evaluate the current heating
or cooling demand and availability of
passive light and heat from the sun.
Louvres or blinds will then be opened or
closed to minimise the energy required
for lighting and heating or cooling.
Electrical lighting will then only be
turned on if it remains necessary.
MAINTENANCE
Access to information related to all of a
building’s systems that can be provided
by a BMS, can help engineers detect
faults and plan maintenance activities.
Maintenance staff would then be more
effective, spending less time diagnosing
faults and more time on preventative
maintenance.
An example of the way that a BMS can
reduce maintenance and make building
systems more reliable is the monitoring
of a sprinkler system. The BMS can
provide information on the status of the
main pump, jockey pumps, panel health
and any fault signals.
To provide central oversight of a
number of local areas, the distributed
sensors and actuators within a BMS
must communicate with the controller.
Standard network protocols such
as C-Bus or Profibus may be used,
although Internet protocols are
becoming increasingly popular. The
Building Controls Industry Association
recommends the use of BACnet, a
communication protocol designed
specifically for Building Automation
and Control (BAC) networks, based
on ASHRAE, ANSI, and ISO 16484-5
standards.
Unfortunately, with computer
networks comes the risk of cyber-
Autumn 2020 www.operationsengineer.org.uk 43
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VHeooslpiait saulsp NpoHrSt sT Urunsitt ebdy Lbientctoelrninshgi breu ildings
Energy teams from resource management company Veolia have extended the services
they provide to the United Lincolnshire Hospitals NHS Trust, one of the biggest acute
hospital trusts in England.
The services will be delivered under an energy performance contract (EPC) with the
aim of lowering costs and cutting carbon emissions across three key hospitals: Lincoln
County Hospital, Pilgrim Hospital in Boston, and Grantham and District Hospital.
By implementing a wide-ranging programme, the contract will look to annually reduce
carbon emissions by 7,712 tonnes, provide £1.4 million of financial efficiencies per year,
build long term energy resilience, and make lasting enhancements to the patient care
environment, according to Veolia.
Measures will include installing new electrical infrastructure upgrades and control
systems for the facilities that cover 74,174m2. They will also include installing nearly
13,000 LED light fittings, a new combined heat and power plant, boiler enhancements
and conversion of the steam system to a low temperature hot water network. The new
plant will be operated and maintained by Veolia’s engineering teams for 15 years, with
investment payback achieved in just over three years.
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