21-1
21
Maintaining the savings
Introduction
Designing the
building
21.1
Post project evaluation
21.2
Continual monitoring
Operating and upgrading
the building
The design process
Managing the building
Design strategy
Acquiring/refurbishing
Sketch design
Maintenance
Specific design
Upgrading energy
efficiency
Checking the
design
Handover
Checking by M & T
Maintaining the savings
This section summarises how and when checks should be made to ensure that energy efficiency measures have been installed
and are operating correctly, and that the savings originally predicted are actually being achieved. It should be read in
conjunction with sections 18 and 20. The PROBE studies(1) show the importance of post project evaluations.
21.1
Post project evaluation
21.2
Continual monitoring
Following the implementation of energy saving measures,
post project evaluation is desirable to establish that
measures have been correctly installed and are achieving
the predicted savings. Small measures may require only a
cursory check but larger projects, e.g. those involving
combined heat and power, require a thorough assessment.
Evaluations should establish:
Continual monitoring helps to maintain the level of savings
achieved over successive years. This requires:
actual savings
final capital cost
impact on occupants
management implications
maintenance issues
other benefits achieved
practical pitfalls.
It may also be possible to compare actual savings with the
savings achieved in published case study material.
Problems identified well after implementation are often
traced back to poor installation.
The energy manager should also provide a post project
evaluation report to senior management on the effectiveness of the investment. For those managing a number of
buildings, the evaluations can also help to indicate whether
similar measures should be incorporated in other parts of
the stock, while highlighting pitfalls to be avoided.
installing monitoring equipment where information is required to assess energy usage and savings
instituting a measuring and analysis scheme and
allocate tasks to personnel
maintaining records of energy use and comparing
them with targets
checking records against utility bills to ensure cost
savings are achieved
reporting results to the building operator on a
regular basis.
The following maintenance and management procedures
also play a large part in ensuring continued savings:
Review maintenance and operating procedures to
ensure that efficiency of plant and system operation
is sustained.
Keep all personnel informed of progress and of
results achieved.
Keep a record of changes to the building and its use
that may effect savings.
Regularly review the monitoring programme and
modify actions where necessary.
21-2
Energy efficiency in buildings: Part B: Operating and upgrading the building
A formal monitoring system is invaluable when assessing
performance and looking for further improvements,
including environmental impact(2). The whole programme
for improving energy efficiency may fall into disrepute if
savings cannot be proved. Confirming the results of
investment helps to justify future investment. Energy
performance monitoring and targeting is examined in more
detail in section 20.
Bibliography
References
Energy audit and survey guide: for commercial and industrial buildings. Energy
audit and survey guide: for building financiers and senior managers Good
Practice Guide GPG 27 (London: Department of Environment, Transport
and Regions) (1991)
Bordass W T, Bunn R, et al. PROBE: Some lessons learned from
the first eight buildings CIBSE National Conference 1997
(London: Chartered Institution of Building Services Engineers)
(1997)
Bartlett P, Bishop T and Durrant H The office toolkit. The guide for
facilities and office managers for reducing costs and environmental
impact BR 285 (Garston: Building Research Establishment)
(1995)
Energy audits and surveys CIBSE Applications Manual AM5 (London:
Chartered Institution of Building Services Engineers) (1991)
Energy audits and surveys Information Paper IP12/92 (Garston: Building
Research Establishment) (1992)
Energy audit and survey guide: for commercial and industrial buildings. Energy
audit and survey guide: for building managers and engineers Good Practice
Guide GPG 28 (London: Department of Environment, Transport and
Regions) (1991)
