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					IEE POWER DIVISION: CHAIRMAN'S ADDRESS



Making Better Buildings and
Making Buildings Better
This is a review paper based on the writer's experience as
a consulting engineer in the field of Installation
Engineering within a multi-disciplinary practice. It is
hoped that it will give an awareness to graduates in
electrical engineering of the immense variety and hence
job satisfaction to be found in this type of work.


by K. A. Shaw

Perhaps some clarification of the term              outdated or inadequate for the client's
'Installation Engineering' is necessary at the      current needs (Fig 2) This is a fairly
outset Installation engineering may be              common category as the basic construction
defined as the utilisation of electrical power      of the building may have a lifetime
within buildings For it to be a safe and            approaching 100 years whereas the
efficient system, the design and selection of       engineering services may be good for only
equipment and fittings to be installed              25 years
together with the method of installation all
must be carried out by engineers who have           The Consultant's role
a diverse range of skills                               The Consulting Engineer's role is therefore
    I was fortunate to spend most of my             to design better buildings, in whichever
career within a multi-disciplinary practice         category, utilising all available technological
and therefore had the opportunity of                i m provement s coupled with in novative
working closely with Civil/Structural               design which may be the result of research
 Engineers, Mechanical Engineers and, to            and development from various techniques
complete the team, Architects In most                   It is not sufficient for the designer merely
 instances the separate disciplines received        to obtain an honours degree, become a
separate appointments from clients, but             Chartered Engineer and thereafter assume
there were many instances where a multi             the role as Consultant It is essential that his
disciplinary commission was received The            (or her) academic career is combined with
great benefit of working alongside others in        practical workshop and on-site experience to
a multi-disciplinary practice was the               such an extent that the candidate can
sympathy and understanding which you                eventually demonstrate 'individual technical       1  Fife House, Fife
developed for many of the problems faced             responsibility'                                   Regional Council
 by others - many of the problems being
unwittingly caused by the designer of the
electrical installation
    To return to the title of this paper,
 'Making Better Buildings and Making
 Buildings Better', the aim of any consulting
 engineer is to meet his clients' requirements
to their ultimate satisfaction If the proposed
 building site is a 'greenfield site' or a vacant
city plot, then the concept i s a totally new
 construction and we have the opportunity of
 designing a 'better building', one that is
 better than those with which the client, and
 perhaps ourselves, have been involved
 previously (Fig 1 )
    The categoly of 'Making Buildings Better'
 comes from the refurbishment of existing
 buildings where the carcase and particularly
 the facade of the building is in good
condition, with perhaps some historical or
 aesthetic significance, but the engineering
 services for the building have become either
POWER ENGINEERING JOURNAL               NOVEMBER 1991                                                                        253
2 The Italian Centre.      The strides being taken by technology        requirements of all forms of Consulting
Glasgow                 demand that the intending consulting            Engineers, there are various issues of the
                        engineer is regularly educated in Continuing    Conditions of Engagement to suit the
                        Professional Development (CPD) schemes          engineering discipline, e.g. civiI/structuraI
                        combined with updates on British                or engineering services, and also to suit
                        Standards, Health & Safety Executive            the extent of the Consultant's involvement.
                        requirements, Building Regulations and          On this latter point, the Client can appoint
                        many other aspects and, for the Consulting      the Consultant on the ACE Abridged,
                        Electrical Engineer concerned with buildings,   Performance or Full Duties form of the
                        the IEE Wiring Regulations.                     Conditions of Engagement depending on
                           The IEE recognises the importance of a       the client's requirements, which are often
                        g o d basic training before a candidate can     dependent on the extent of his own
                        become Chartered. The trainee Consulting        available manpower or specialist expertise
                        Engineer may receive his practical experience   or the type of installation contract
                        within the Contracting Industry and be able     envisaged.
                        to discover the joys and hardships on site of      The 'rules of the game' for the
                        installing and commissioning a system -         Consulting Engineer engaged in
                        designed by othen. Currently there are more     Installation Engineering are detailed in Part
                        and more Consulting Engineers practices         4A of the ACE Conditions of Engagement
                        which provide graduates with approved           and are carefully considered by Client and
                        training within their own offices, and 'on      Consulting Engineer prior to an
                        site' experience is obtained where              appointment being offered and accepted.
                        supervisory duties have to be carried out or       In general, the duties may be
                        where the Consulting Engineer is asked to       summarised as follows:
                        provide Resident Engineering staff for the
                        duration of the contract. The Engineering           Establish a brief - in discussion with
                        Council has drawn up a training and site            the client.
                        experience scheme referred to as Standards          Carry out a feasibility study and report.
                        & Routes to Registration (SARTOR), and this         Prepare a preliminary plan with sketch
                        provides a basic accreditation for training         proposals and budget costs.
                        and site experience in order to achieve             Further discussions with client with
                        chartered status.                                   approvals or amendments as
                           Many consulting engineering practices            necessary.
                        co-operate with contracting organisations           Proceed to final design and tender
                        so that the candidate may obtain training           documentation.
                        in all fields.                                      Carry out cost check.
                                                                            Discuss with client and receive
                        The rules of the game                               approval or amendments.
                           The Conditions of Engagement, as                 Select list of tenderers.
                        prepared by the Association of Consulting           Issue tender documentation.
                        Engineers (ACE), provide suitable formulae          Prepare a report on tenders received
                        for the engagement of a Consulting                  giving recommendations for
                        Engineer, the obligations of the Client, the        a'cceptance.
                        professional services t o be provided and a         Advise tenderer of client's acceptance.
                        basis of payment for these services.            (m) Discuss programme for the works.
                           As the Association covers the                (n) Provide site supervisoty/resident
254                                                          POWER ENGINEERING JOURNAL             NOVEMBER 1991


                                                                I
    engineering staff or check the                  There are, however, many other 'rules of
    adequacy of site supervision by others.       the game' with which the Consulting
(0) Witness Testing and Commissioning.            Electrical Engineer specialising in buildings
(p) Arrange for Handover and Completion           must be totally familiar, namely:
    Certificates
                                                  (i) Regulations for Electrical Installations
(9) Check the Works prior to expiry of the
    Defects Liability period.                           (the Wiring Regulations)
                                                  (id Health & Safety at Work, etc. Act 1974
  The stages for these duties are well            (iii) Electricity at Work Regulations
  defined in the Conditions of Engagement,        (iv) Building Regulations
  and the client is able to check a t any point   (v) Fire Precautions Act 1971
 the extent of professional services carried            (Modification) (Revocation) 1989
  out and therefore the extent of payment         (vi) British Standards
  due. In this way, if a design proposal is       (vii) European and International Standards
  proving to be too costly, it can be aborted,
  or if the client can provide his own             to name but a few technical requirements
  supervision, the Consulting Engineer is          plus, of course, various conditions of
  only required 'to make such visits as           contract, such as JCT, IEE/IMechE/ACE
 considered necessary by the Consulting            Model Forms etc.
  Engineer'.                                         It takes a considerable number of years
     The selection of a Consulting Engineer       of experience to become conversant with
  can be undertaken in various ways.              such a plethora of publications, but
     The ACE has details of all member            nonetheless it is essential in order that the
 practices and can give advice to clients on      project can be totally 'in accordance' with
 firms who have the necessary expertise for       the requirements of safety and thereby
 the work in prospect. The final selection        acceptability.
 will normally be by fee competition, but it         The task of keeping the practice up to
 should be against a well-prepared project        date is one normally partly allocated to
 brief. In some instances the brief is in         your qualified librarian who will ensure
 vague terms and the time for submission          that all references are continually updated,
 extremely limited, which results in a wrong      that you are suitably informed when
 appointment for the wrong reason.                amendments are issued and that, when
 Fortunately, most clients are in the             you are commissioned for a special
 category of 'informed clients', i.e. they        project, you have all the statutory
 have engaged Consulting Engineers                requirements on hand for immediate
 previously and they have qualified               reference. CPD also plays a considerable
 engineering staff who know what is               part in this task.
 required in sufficient detail to prepare a          Having reviewed the 'Rules', let us now
 proper brief.                                    consider w h o would ask us to 'play'.
    Some clients favour the commissioning
of a single professional in a Lead                Who is the client?
Consultant's or Project Management role              In the same way as we have a variety of
and the selection and engagement of the           buildings and a bigger variety of users, we
Sub-Consultant is left with him. We have          find an endless variety of clients. Clients
found this quite frequently in our practive,      may occupy similar types of building but,
particularly where the value of the civil or      depending on their individual operations,
structural engineering works is substantial       they will undoubtedly have differing
and our other Partners within the Practice        requirements. Our practice classified
take the leading role as Civil/Structural         clients in the following categories:
Engineering Consultant and appoint us as          (a) Public utility : power station, water
their Sub-consultants for the Engineering                              treatment works
Services. This gives the client an easier         (b) Local authority: schools, colleges, leisure
mode of control as the communicating                                   facilities
channel for all requirements is via the one       (c) Commercial : offices, banks, hotels
body.                                             (d) Industrial     : factories, petrochemical,
    Other routes for selection are via                                 fisheries
Management Contracting, Construction              (e) Government : prisons, defence works,
Management and a variety of Design and                                 hospitals.
Build schemes, all of which can be quite
acceptable provided that great care is            We find, however, that clients do have
taken at the outset to ensure that all            common aims with regard to their basic
aspects of the appointment are                    priorities:
understood by the parties concerned. The
ACE has a Professional Practice Committee         (a) Flexibility in use and, if possible,
which can give advice on such matters.                potential for extensions
    In any event, in the selection of a           (b) Automation - the intelligent building
Consulting Engineer, it is important for          (c) Innovation - tempered by optimising
clients to include comparison of resources            capital and recurring costs
and expertise in the selection process and        (d) Good environment
not simply consideration of a fee                 (e) Security
quotation.                                        (0 Maintainability.
POWER ENGINEERING JOURNAL             NOVEMBER 1991                                                 255

                                                                    I
      In new build, our 'better building'                  to the Wiring Regulations to summarise
      category, the building may be an entirely            the differences between the 15th and 16th
      new development with no opportunity to               Edition, as it is a specialised topic in itself
      examine how the client operates or the               and the IEE successfully runs two-day
      problems that need to be overcome You                courses on the subject throughout the UK
      are dependent on the communication of                on a virtually continuous basis One of our
      the client's requirements to you and your            own Associates has assisted the IEE as a
      correct interpretation of these                      part-time lecturer for almost eight years
      requirements It i s also vital to know the           now
      correct questions to ask At this stage, all              However, perhaps a few comments
      discussions have to be carefully recorded,           would be appropriate
      notes made of visits to other sites,                     Much of the support information
      telephone calls and minutes of meetings,             contained in the 15th Edition has been
      formal and informal When the project                 omitted from the 16th Edition Wiring
      flows with ease from start to finish, it i s a        Regulations, and the IEE will be providing
      sign that communication between client               a series of Guidance Notes containing the
      and consultant has been excellent                    necessary data I t is intended that these
         In the case of a refurbishment project,           will be fully issued by the end of 1992 as
      making a 'building better', you may at               the 16th Edition comes into force on the
      least have the opportunity of observing the          1 s t January 1993 In the meantime, the
      client in operation, and in this respect you         Appendices of the 15th Edition should
      will be able to have a greater input to the          provide quite acceptable data for design
      preparation of the brief, but in all other           guidance (or perhaps divine guidance)
      matters the procedure is quite similar                   There is an enhanced numbering system
         There are many reasons for considering            based on the previous system for the
      refurbishment Perhaps the premises                   regulations of the 16th Edition but, to
      require upgrading to satisfy current                 assist the users, some independent authors
      legislation or to improve the technical              have prepared cross reference material
      efficiency of operation The end result               which could be very useful initially, until
      should certainly give a more contented               the user becomes familiar with the revised
      and productive workforce Effective                   format
      refurbishment can prove to be more cost-                 The general intent of the Regulations
      effective than a move to new premises by             has certainly not changed, but there must
      uti I i s i ng corporati on tax incentives through   have been problems of interpretation over
      lease purchase agreements As in all types            recent years as much of the wording is
      of projects, a detailed financial appraisal          now more commanding and demonstrates
      must be undertaken and strangely                     an ever increasing responsibility on the
      enough, finance appears to carry greater             Consulting Engineer/lnstaller A major
      weight than historical or aesthetic                  modification is in the assessment of
      appearances                                          voltage drop, although the basic
         Whatever the requirements of a client             requirement is still for the safe functioning
      are, they have come to the consulting                of equipment The requirement i s now
      engineer for professional advice and they            based on the voltage drop between the
      are due to be given that advice without              origin of the installation and the fixed
      bias or commercial influence Although                current using equipment, and i t should
      most clients are looking for a capability to         not exceed 4% of the nominal supply
      translate their proposals into practice it           voltage The Consulting Engineer will
      should be remembered that good advice                require to pay careful attention to this
      can also be counter the proposal, perhaps            matter as the supply voltage can still vary
      directing the client on a more suitable              by +6%, the -6% being a potential
      route Communication skills are an                    problem area where a total drop of 10%
      important adjunct to an effective                    might occur Careful design will, however,
      Consu Iti ng Engi neer                               result in the provision of a 'better
                                                           building
      The IEE link - Wiring Regulations                        We now have the benefit of a new
         No paper could be prepared in the year            section on 'Special Installations or
      1991 and discuss Installation Engineering            Locations - Particular Requirements'
      without making due reference t o the I E E           which covers swimming pools, saunas,
      Regulations for Electrical Installations, 16th       construction sites, caravans, caravan parks,
      Edition                                              highway power supplies and street
         This recent edition should not cause              furniture This section either supplements
      Consulting Engineers and Installers the              or changes the requirements as contained
      same degree of trauma as did the 15th                in other sections and has therefore to be
      Edition which, almost unbelievably, was              read in conjunction with the requirements
      issued some ten years ago The 16th                   of other sections This part is indeed an
      Edition i s the same size and the cover i s          enhancement to the 15th Edition and i s
      the same colour as the previous issue, but           surely an eye-opener to those unfamiliar
      beware, much of the contents are                     with Installation Engineering, as it
      significantly changed                                illustrates the immense coverage of the
         It is not intended in this brief reference        Regulations
256                                             POWER ENGlNEERlNG JOURNAL              NOVEMBER 1991

                                                  I
    Vibration gets a mention for the first       requirements and i t is at this stage that
time Our practice is, as previously              you should remind yourself that both of
 mentioned, multi-disciplinary and the Civil/    you were engaged possibly as a result of
Structural section has, for many years,          submitting the most competitive offer This
been responsible for the design of               is not the time for contemplation, all
structures in seismic areas Vibration is,        actions must be positive, instructions clear
therefore, not an unknown problem but i t        and the Works carried out without delay
is hoped that, for the UK at least, i t i s         The Works must be properly managed
 intended as guidance for installations          with regular site meetings, timeous
affected by man-made vibrations There            production of minutes, agreed procedures
are of course areas in the UK prone to           for Site Instructions, regular visits of
subsidence and the Regulations allow for         supelvision, timeous approval of payments
this by stating that the installations require   for work completed, agreed procedures for
to be 'suitable for the movement of the          testing, commissioning and handover -
structure of the building'                       together with many other matters to
    Another new entry i s the reference to       ensure a successful installation
'Foreign National Standards' and with               On completion, the Electrical Contractor
 1992 fast approaching perhaps a                 will provide you with correct records of the
definition of 'Foreign' requires clarification   installation, test results, spares and 'As
    How do we monitor Consulting                 Fitted' Record Drawings together with
 Engineers and Design Contractors from           Operating Instructions for specific sections
outwith the UK, designing and installing         or equipment
 here to their own national standards and           Having 'handed over' tor operational
not in compliance with ours?                     use, it is as well to enter a note in your
    There is now an increasing amount of         diary for 1 1 months time to contact the
suspect equipment supplied to us from            client and revisit the site for a final look
outwith the UK One i s liable to receive         around before expiry of the Defects
'factory built assemblies' with live             Liability period and the final amount of
terminals not protected, isolating facilities    retention monies are paid
not provided and a host of single green
cables (phase and earth) none of which           The finished article
complies with our Standards The                  (a) Newbuild - House of Fraser,
Consulting Engineer must exercise great          Meadowhall Shopping and leisure Centre
care in preparation of his specification            Meadowhall i s a wonderful name for a
otherwise compliance with the signing of         site that was previously occupied by a
Completion & Inspection Certificates             steelworks The Meadowhall Shopping and
 becomes a problem - if not impossible            Leisure Complex, adjacent to the M 1 at
                                                 Sheffield, will cater for up to 30 million
Managing the project                             shoppers each year with access to all the
   The successful Contractor has been            shopping units being under cover and car
appointed and the pre-contract meeting           parking for 12 000 cars
                                                    Within the complex the House of Fraser
has been held to introduce all the
                                                 has some 10 000 m2 of prime retail area
responsible parties to each other
   You may be fortunate t o have a Project
                                                 encapsulating traditional decor of up-
                                                  market design, creating an ambience of
Manager, a Lead Consultant or Architect
to take the reins but, whatever the case,        quality and luxury (Fig 3) The client
someone has to take the ultimate                 appointed the design team In March 1989        3   H~~~~ of Fraser,
responsibility and provide the client with       with the primary objective to have the         Sheffield

the correct installation, preferably on time
and a t the agreed cost
   It i s all too easy t o consider that your
particular aspect in the provision of
Engineering Services should be provided
with your absolute selected location,
access, cable routes and means of
maintenance However, present-day
buildings are becoming increasingly
complex with a proliferation of necessary
services for heating, ventilation, air
conditioning, plumbing, communication
systems, security systems, fire alarm and
detection systems and the like - all of
which points to early preparation of
detailed co-ordination drawings which not
only should serve to avoid the clashing of
services but also should maximise the use
of available space
   It is now up to the Electrical Contractor
to implement your design to your
satisfaction and to the client's precise

POWER ENGINEERING JOURNAL             NOVEMBER 1991                                                                    257
      premises complete with a budget target of      management t o operate efficiently and
      f8.2 million by September 1990, a design       safely.
      and fit-out period of 17 months. In the
      event access t o the site was not possible      Ventilation and comfort cooling
      until January 1990 which in effect cut the         In the retail areas there is sufficient heat
      on-site programme to 9 months.                  dissipated from 280 kW of general and
         Close co-operation between all design       feature lighting to eliminate the need for
      team members and the client was vital t o      any boiler generated heating. Four roof-
      the success of the project.                     mounted air-handling units are installed to
                                                      serve the retail areas, each in turn being
      Contract                                       served by electrical direct expansion heat
          The restricted programme ruled out          pumps which, for control purposes, fed
      conventional competitive tendering             direct expansion coils piped in a
      procedures and t o meet the programme           serpentine manner in the air-handling
      strictures, while maintaining cost control,     units. The air-handling units have the
      i t was resolved t o adopt the JCT form of     facility t o recirculate a proportion of the
      Management Contract which resulted in          air, always allowing for a minimum fresh
      the contract being let in November 1989.       air setting. On initial start up during winter
          A detailed design and construction         months the fresh air, extract air and
      programme was generated establishing            recirculated air dampers regulate to the
      work package sequence through from             minimum fresh air position and the heat
      design to site implementation. Long             pumps operate in a heating mode,
      delivery items of equipment and plant          reverting to normal cooling/heating once
      were identified at an early stage and          the desired internal temperature is
      procurement letters were issued following      reached.
      pre-tender exercises. The Quantity Surveyor        Due to the nature of the store, there are
      in conjunction with other disciplines          various display areas with large lighting
      subjected each work package to value            loads, and great care had t o be taken to
      engineering exercises as well as strict cost   ensure that sufficient air is directed to
      procedures. The Management Contractors         these areas for cooling purposes without
      provided ideal 'buildability' input.           causing uncomfortable draughts yet not
          During the on-site phase, costs were       compromising the general aesthetics of
      constantly monitored through detailed          the ceiling design. Three additional roof-
      financial reviews and progress of each         mounted air-handling units are installed t o
      work package compared against the              serve the administration areas, coffee shop
      overall construction programme. The result     and staff restaurant. These areas are also
      was a project constructed on time and          served by heat pumps; however, as they
      within budget.                                 are without the same internal gains as the
                                                     retail areas, back-up low-pressure hot
                                                     water is provided.
      Building services                                 The shopping mall area has its own
         We were commissioned by House of            independent smoke extract system which
      Fraser to be the Engineering Services          is designed to cope with large fires within
      Consultants The 'landlord's' sewices were      the complex. Within the store the Fire
      made available by the developer's team of      Officer's concern is for fires up to 5MW.
      Consulting Engineers and this covered the      To satisfy the Fire Officer's requirements,
      infrastructure of water, gas and electricity   door curtain smoke extract systems are
      supplies The brief was to provide the          designed for each level (slit extract) t o
      highest standard of customer comfort           ensure that low-temperature smoke, up to
      using the latest technology Safety             150°C. would be directed t o a specially
      standards were of extreme importance           designed catchment area and then
      involving extensive discussions with all the   extracted t o atmosphere. This system is
      relevant statutory authorities The planning    augmented by the general retail area
      disciplines on a fast track programme are      extract units, so care is taken t o ensure
      extensive and progressing of information is    that the motors serving these fans are kept
      paramount Comprehensive scheduling             out of the airstream.
      and monitoring of all requirements was            In total there are 18 air-to-air heat
      carried out                                    pumps installed to operate in conjunction
         The services installed are general and      with the air-handling units. The total
      feature lighting, electrical power,            cooling capacity of these units is some
      escalators, lifts, heating, comfort cooling,   800 kW.
      domestic water services, sprinklers, CCTV,         By incorporating this capacity of heat
      public address, voice and data cabling,        pumps in the design, we achieve extremely
      security, fire alarms, standby generating      low running costs - very much t o the
      equipment and smoke extract systems all        client's satisfaction.
      under the control of a comprehensive
      Building Management System The                 Heat sources a n d distribution
      concern of the designers was to provide          Three gas-fired boilers are installed to
      warm familiarity and a comfortable             provide low-pressure hot water to serve
      pleasant atmosphere within the store to        the three air-handling units previously
      attract customers and enable retailers and     mentioned, unit heaters in the loading bay
258                                        POWER ENGINEERING JOURNAL              NOVEMBER 1991


                                             I
and radiators in the administration areas.       lighting and power network. These control
The LPHW distribution is split into four         lines are present at each lighting and
separate pumped circuits. The total boiler       power section board and are used t o
power is 600 kW which, for an area of            control relays and contactors giving power
some 10 000 m 2 and virtually all air            control, security lighting, cleanerslstaff
heated, is very low and is possible due t o      lighting and main lighting. Individual
the fact that heat pumps are installed to        relays are used on the lighting circuits t o
provide heat energy recovery.                    give the store maximum flexibility of
   A comprehensive Building Management           operation. As previously stated it is also
System (BMS) is provided to control the          linked to various services where it monitors
various plant functions. These include           and records alarm signals and fault
monitoring of the sprinkler system,              conditions, providing permanent records,
lighting, security, fire protection,             via its printer, of any occurrences in the
temperatures etc. A main control panel           store.
located in the rooftop boiler room houses
the electrical/electronic control elements.      Lighting a n d small power
The panel also contains the auto/manual              Lighting in the retail area is installed t o
switching functions for each plant item.         match the themed areas of the store. With
                                                 this in mind a variety of light sources are
                                                 used.
Mains distribution and standby generator             In the furniture department the main
    The electricity supply is derived from       lighting consists of modular louvred
Yorkshire Electricity's 11 000 V ring main       fluorescent luminaires with highlighting
for the site, via a radial feed from the         provided by track-mounted 1 2 V dichroic
ci rcuitbrea ker and metering equipment.         spotlights. The cosmetics department
    On entering the store the supply             utilises recessed PL downlights with
terminates in the package substation. This       highlighting provided by recessed
consists of a cast-resin dry transformer
                                                 adjustable 75 W spotlights, the fittings
with an ambient rating of 1600 kVA, fitted       being set out in the ceiling t o mimic the
with cooling fans to give a total capability     layout of the counters. Other departments
of 2200 kVA. The L side of the
                      V                          are treated in a similar manner.
transformer feeds a 3000 A SF                        The main walkways on the upper level
circuitbreaker. The output of tkis is split      are lit by batten fluorescent luminaires
and feeds a 3000 A busbar feeder to the          recessed in an architectural trough formed
essential services main board and also via       in the complex ceiling. Surface-mounted
a 600 A fuse switch t o the non-essential        cold-cathode tubing on the formed
services board.                                  bu Ikheads enhances the wa Ikways.
    The essential services busbar is             Additional display lighting is provided by
 mechanically and electrically interlocked       tubular fluorescent and dichroic lamps
 with the standby generator, a roof-             built into the display cabinets. In non-retail
 mounted 800 kVA machine in an acoustic          areas, fluorescent and discharge lighting is
 enclosure with diesel storage tank located      used.
 on the ground floor. The generator is sized         The lighting load for the store is
 to provide sufficient alternative power to      approximately 280 kW with the number of
 enable the store to continue trading             light fittings in excess of 5000
 should the normal electricity supply fail,
 the standby capacity being around ten           Fire-alarm and emergency lfghtfng systems
 working days. Lighting and power                    The Fire-Alarm System is of the
 requirements are met by various section         analogue addressable type with the main
 boards located throughout the store. These      panel in the Security Room and a repeater
 lighting and power section boards consist       panel at the lower car park entrance to
 of two independent MCB boards, one for          assist Fire Brigade personnel on call-out.
 power and one for lighting. In retail areas     The system consists of four loops to which
 the power board is contactor controlled via     are connected over 400 devices with
 the BMS computer.                               detectors both above and below ceiling
    The lighting boards contain a multi-relay    level. The alarm consists of a two-stage
 section where lighting circuits have            system, stage one alerting the staff areas,
 individual relays controlled via the BMS        and stage two evacuation of all areas.
 computer.                                       Activation of both systems is via a digital
     Services distribution is generally within   annunciator within the public-address
 the ceiling void with dedicated trunking        system.
 runs for small power, computer data,                Emergency lighting is provided by
 telephone and security. A large cable tray      individual battery packs to selected
 network is installed for the support of sub-    fittings. Exit lighting in the retail area is
 mains cabling, fire-alarm cabling and           provided by maintained edge l i t fittings
 Public-Address Systems, the latter two          with all other areas using non-maintained
 being wired in PVC/MICC cable.                  wall-mounted box signs.
                                                     Generally speaking this is a most
Building management system                       successful project but, as in many
  The BMS computer generates four                Installation Engineering projects, a project
separate timing control lines for use of the     is most successful when it is not really
POWER ENGINEERING JOURNAL             NOVEMBER 1991                                                 259
                                                                      i t s 12 storeys. The external wrapping of
                                                                      the inner shell comprises a communicating
                                                                      series of corridors and on the outer edge a
                                                                      number of administrative rooms for
                                                                      offices. In this way the inner sanctum is
                                                                      isolated from external city noise in the best
                                                                      manner possible.
                                                                           There are three basement floors which
                                      ,-                               help to house most of the engineering
                                                                      plant, boilers, air-conditioning plant, lift
                                                                       motor rooms, standby generators and
                                                                      main switchgear. Some plant has been
                                                                       located on the roof, but roof space is at a
                                                                       bigger premium and is very much subject
                                                                      to Planning Approval.
                                                                           The BBC has for some time now been
                                                                       involved in the upgrading of its
                                                                      engineering services. Its plans cover for a
                                                                       20-year projection of the necessaly
                                                                      facilities including capacity of supply,
                                                                       power density, power distribution, lighting
                                                                       upgrading, standby generation and
                                                                       ancillary services.
                                                                           The BBC's supply intake is at present
                                                                       from thirteen 41 5 V services. This is being
                                                                      changed to accept supply at 1 1 kV via four
                                                                       transformers on the basis that three out of
                                                                      four will provide 100% total load. As the
                                                                       BBC must have a 'we never close' policy,
                                                                       there will be an ultimate standby
                                                                       generation facility of 2.4 M W which will
                                                                       support 100% of the load for at least a full
                                                                       24 hour operational period. To cope with
                                                                       time delay before the standby generators
                                                                       are operational, and to provide a
                                                                       'conditioned' supply for sensitive broadcast
                                                                       equipments, there is a 500 kW UPS
                                                                       (uninterruptible power supply) system
                                                                        installed.
                                                                            The UPS system (Fig. 5) copes with
                                                                        broadcasting requirements including some
                                                                       operational lighting, main broadcasting
4  Broadcasting House,   noticeable, which is a pity at times from      systems and sustained escape lighting.
London                   the point of view of job satisfaction         Services to the restaurant, lifts, production
                                                                        offices and general services are interrupted
                         (b) Refurbishment - 66C                       only for a brief period. The UPS system can
                            One particular client who has a specific    operate at full load for up to 15 minutes,
                         policy of 'making buildings better' i s the   which is a special requirement ;vel1 above
                         British Broadcasting Corporation In the       the normal period for standby generator
                         BBC's case, many of the buildings,             load take-up.
                         including Broadcasting House itself, have          The provision of 2.4 M W of standby
                         outgrown their engineering services and       generation, located internally, causes
                         the technology which i s now available IS      problems of cooling. Other alternatives
                         totally different Also the management and were examined, i ncl ud i ng roof-mounted
                         staff are looking for a more flexible and      gas turbines, but for various reasons the
                         improved environment                           present system using four diesel units will
                             Although there has been considerable       be retained. One of our studies was an
                          redevelopment at the BBC's White City        examination of space availability to provide
                          location, there are good reasons for          sufficient air t o overcome the rejected heat
                         continuing to have a presence in the West from the engines and radiators and the
                          End - and i t is not merely for historic      final installed solution was a combination
                          reasons, the image or the overall character  of the use of condensers and chilled water
                          of the Corporation, albeit the importance     together with jacket water to the roof and
                          of same                                      the use of roof fans. In all this work of
                             Broadcasting House itself (Fig 4) is a     cooling, the client and ourselves were very
                          unique building, constructed in 1931 and     conscious of the Legionella problem, and
                          purpose made for its special requirements     considerable care was taken at the design
                          The inner shell is constructed of Portland   and commissioning stages to ensure that
                          stone and houses a Concert Hall and many the system fulfilled all requirements.
                          other Radio Broadcasting facilities within        In assessing the future electrical load

260                                                           POWER ENGINEERING JOURNAL            NOVEMBER 1991


                                                                 I
requirements, the initial guidance was               Linked with the Fire-Alarm Systems we
taken from ClBSE Design Guide Values,             had emergency lighting systems and in
but there was always an appreciation of           some instances security alarm systems,
the structural capability of the building         particularly where addressable systems/
and that if a load of 100 Wlm’ was                intelligent systems were installed In this
reached then the building would overheat          way we were able t o make full use of the
Great care was taken with the load                capabilities of the installed system I t was
analysis with a reduction t o the values          recognised in each case that the system
given for areas in general office use and         installed should be as simple as possible
an increase in the values given for areas         and that the operators of the system had a
housing computer facilities, the largest          complete understanding of the
increase being taken for the News Room            information provided
area which i s another special case                  In all the foregoing, the installations
    In assessing the lighting requirements,       required t o be carefully CO ordinated so
to ClBSE Lighting Guide, there are                that the broadcasting operations were not
numerous other aspects to be considered,          disturbed, and to this end the BBC’s
including the operational function, the            Project Management team have to be
options of task and general lighting, the         congratulated
degree of freedom afforded to the users
and the type of control, and it should be         (c) New build - ice rinks
 remembered that the ClBSE Lighting Guide             Leisure ice - we are now generally
is, as i t s title suggests, not mandatory        familiar with leisure swimming pools but is
 More precise information may be available        this not the ’Electric Ice Age’? Gone are
by examination of a client’s existing             the days when the simple area of
operations and evaluation by needs                rectangular ice was sufficient for our
assessment techniques                             entertainment In line with the present day
    Part of the upgrading throughout BBC‘s        swimming pool design, which incorporates
property has been with regard to Fire             palm trees, islands, flumes and wave
Alarm Systems The installations were all          machines, we now have free-form ice and
carried out in accordance with BS 5839            in fact t w o level ice in one of our special
and varied in complexity and format in            projects
accordance with the use of the building               Many ice rinks (Fig 6) now operate in
    Where the BBC has studios t o which the       conjunction with swimming pools and
general public is admitted, there i s always      other sporting activities in order to provide
a Fire Officer in attendance and all Fire         for the increasing leisure needs of our
Alarms and signs are under the control of         population This combination of extreme
the Fire Officer during the performance           cold and warmth gives the ideal formulae
Where there are Iivr microphones, bells           for the application of multiple energy
are not used at all or muted, flashing            conservation measures as opposed to an
signals are employed t o ensure that              individual application for one particular
 spurious alarms are not broadcast                facility In an ice rink installation the heat
Although a two stage system is installed,         rejection from the ice plant i s passed
the initial detection will operate the first      through a closed circuit cooling tower          5 UPS switchgear,
 stage and this will alert the Fire Officer and   and, as it is still low-grade heat, water to    Broadcasting House
all staff in readiness for evacuation If on
 investigation the situation is not
 dangerous then the alarm is reset If,
 however, there is a possible fire risk then
 the second stage will function and normal
 evacuation procedures will take place
    BS 5839 calls for a sound level of
 65 dBA or 5 dB above the ambient and in
 designing t o an L1, L2 or L3 standard we
 have found it to be inadequate in many
 cases to adopt the suggestion that one
 door between the sounder and the area
 concerned should still give a satisfactory
 65 dBA A high degree of flexibility has to
 be designed into the system and in this
 respect volume controls on electronic
 sounders can be of great assistance -
 provided that Fire Drill Tests are carried out
 on a sufficiently regular basis to allow the
 occupants to be familiar with the alarm
 and the action required
     It is essential that audibility tests are
 carried out under normal operational
 conditions and the results recorded in a
  suitable form in the Operating Instructions
  Manual
POWER ENGINEERING JOURNAL              NOVEMBER 1991                                                                   261
                     water heat pumps are utilised in order to         (d) Refurbishment - John Menzies plc
                     use the resultant heat in the ventilation            The potential of an energy-saving design
                     plant The main use of this recovered heat         is always attractive in a refurbishment
                     is to provide heating to the structure at         project An opportunity arose when John
                     high level to ensure that condensation            Menzies plc required to upgrade their
                     does not occur                                    shop premises at Dundee
                        Any excess of recovered heat can always            Detailed studies at the 1500 m 2 store
                     be used up to supplement the Domestic             revealed that frequently in winter the store
                     Hot Water supply for the kitchen services         would need heating at the front, near the
                     or shower facilities Where there is an            entrance, and at the same time need
                     adjoining swimming pool, the pool itself          cooling at the rear of the shop - this
                     will always welcome recovered heat It is          being due t o the shop’s deep-plan format
                     interesting to note that the electricity          and the high levels of occupancy and
                     supply companies are not anxious about            lighting
                     the type of fuel used for the main boiler            The solution to the problem gained the
                     plant which creates the initial load, but         company a Beta Award in recognition of
                     they are anxious about the heat pumps             the significant contribution to energy
                     which give them a constant load                   efficiency using electricity The design
                        The illumination of ice halls varies in        called for two separate air-to-air heat
                     design with the aesthetics of the structure       pumps to be installed along with a simple
                     Generally the light sources require to be         but innovative control system This
                     efficient and carefully sited to give a            basically removed the excess heat from the
                      uniform level of lighting along the line of      deep-plan area to supplement the
                      Play                                              requirement for heat at the entrance area
                         Play, in the North, means curling, and        The control system ensured the maximum
                     two levels of lighting are normally                use of free cooling from outside air by
                      required, one for normal matches and the         adjusting automatically the balance of
                      other for televised events Maintenance of        fresh, exhaust and recirculated air Carbon-
                     the luminaires has to be carefully                dioxide sensors within the shop were used
                      considered and the consulting engineer           to control the precise quantity of fresh air
                      should have early discussion with the user       input in relation to the number of
                      in order to have facilities within the project   occupants
                     for maintenance of all equipment                      Additional energy savings were made by
                         The remaining electrical services are          discharging the warm air over the outside
                      merely the standard requirements for             coils of the heat pumps when they were
                      plant, small power, kitchen, fire-alarm           being used in the heating mode When
                      system and intruder alarm systems, but an        the units operate on the cooling cycle a
                      essential requirement is first-class public       heat exchanger allows preheating of the
                      address and music systems, the latter             shop’s domestic hot water thereby making
                      being linked into a disco lighting system         use of heat which would otherwise be
6 Auchenharvle ice    where the degree of sophistication is            wasted
Rink                  limited only by budget                               The design of the installation was so
                                                                        successful that the client decided to use
                                                                        similar systems in a number of their other
                                                                        outlets throughout the UK, not only in
                                                                        refurbishment schemes but also in new
                                                                        developments

                                                                       Europe - our neighbours
                                                                          Consulting Engineers have worked
                                                                       outwith the UK for a number of years In
                                                                       the past, emphasis has been on the
                                                                       ’overseas‘ or ‘international’ scene,
                                                                       principally in the Third World where
                                                                       engineering expertise was required and
                                                                       funding was from World Bank resources
                                                                       These projects were to develop essential
                                                                       supplies of water and power to enhance
                                                                       whatever natural resources were available
                                                                       and thereby upgrade the standard of living
                                                                          In Europe we have a different situation
                                                                        entirely
                                                                          In many countries the expertise is well
                                                                        established, the standard of living is as
                                                                        high as in the UK and there appears to be
                                                                        ample resources for progress in such
                                                                        matters as Research and Development -
                                                                        and certainly at a higher level than in the
                                                                        UK Our future in Europe must not be
                                                                        looked on as a threat, more as an
262                                                          POWER ENGINEERING JOURNAL            NOVEMBER 1991

                                                               I
opportunity Even if we do not intend to             Are you aware of the European
take the opportunity to expand our               Community's requirements for the
business we should certainly take any            'assessments of the effects of certain
opportunity in the formulation of                public and private projects on the
Standards, Laws and Directives with which        environment'? If not, the Directives list
we will be required to comply in the very        guidance for projects such as thermal
near future                                      power stations, chemical installations,
    The Association of Consulting Engineers      holiday villages and knackers' yards
i s playing a key role in the discussions of         The foregoing refers to matters affecting
 draft Directives in order that the profession    the Consulting Engineer as he ventures
will not be disadvantaged                         into Europe There i s of course the reverse
    The work i s wide and varied, at times        route where the European countries will
frustrating but nonetheless essential in          bring their wares to the UK and - as
 order to create acceptable principles for        referred to previously under 'The Wiring
our future                                        Regulations' - who will have the task of
    Directives include such activities as         monitoring the resultant installations?
0   Public procurement of sewices open to        The future
    competition to Consulting Engineers of          The content of engineering sewices in
    all nations                                  bui Idi ngs has increased significantly in
0   Euro Codes & Standards construction          recent years Installation Engineering has
    standards to design codes                    close links with the developments in
0   In-house engineering removing the            electronics technology and as such there
    inequities within the Community              has been continuous progress in the
0   Professional liability the preparation of    provision of new facilities in buildings
    a sectoral Directive for construction        such as Building Management Systems,
0   Development co-operation the use of          Security Systems, Data and Communication
    the European Developments Fund               Systems and many others Even in the
0   Directive for engineers to resolve the       domestic market we are on the brink of
    difference in engineering status             Home Bus Systems via which domestic
    between the North and South European         eq u i pment, with integ ra I electronics,
    nations (yes, they have their status         communicate with each other
    problems as well)                               In addition to the technology explosion
A complementary role on behalf of the            there is considerable attention being paid
electrical contracting industry is played by     to the protection of the environment -but
The Electrical Contractors' Association of       perhaps not enough The recently
Scotland which, a s a result of i t s            announced Environmental Protection
participation within the International           Agency may be able to establish the
Association of Electrical Contractors (AIE)      necessary legislation as i t s policy i s
i s involved in IECKENELEC work and              widespread, from eco-labelling to
monitors some IECKENELEC documents               environmental education. but meantime
including                                        we must keep our aims on the highest
                                                 plain possible
0   types of systems earthing                       The Consulting Engineer has the
0   voltage drop in consumers' premises          continuous challenge of finding the most
0   selection and erection to minimise the       effective and innovative design solutions in
    risk of fire                                 keeping with current standards for the
0   proximity of other engineering sewices       efficient use of energy Effective solutions
In addition, the AIE is on the verge of an       will cause a reduction in load capacity as
agreement which would allow direct input         well as in running costs Research has
to the European standards making                 established that improvements to buildings
process The Technical Committee                  by energy efficient design could lead to a
chairmanship and secretaryship of the             15% reduction in the total CO, emissions
International Association (AIE) are both         in the UK
held by the UK                                      A recent assessment of the potential
   A number of UK firms have already             market for environmental technology in
made application to Brussels for                 the UK alone was some f140 billion over
consideration in the Thermie programme           the next decade - so there i s a future, a
which gives EC funding of up to 40% for          future t o make 'better buildings' and a
projects to improve future energy supplies       future to make our existing 'buildings
and energy utilisation in buildings - so it       better '
is certainly not all bad news                     Delivered before the I E E Power Division on the
   The European Commission has countless          23rd October 1991
topics 1992 is to be the European Year of
Health & Safety How does our 'Health &            B I E E 1991
Safety at Work, etc Act' and 'Electricity at
Work Regulations' compare with those of           Ken Shaw is a Consultant with T Harley
other European countries? If you are a            Haddow & Partners, Consulting Engineers, 10
consulting engineer working in that               Newton Place, Glasgow G 3 7PR. UK He is an
country, you will require to find out             IEE Fellow

 POWER ENGINEERING JOURNAL            NOVEM BER 1991                                                 263

				
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