Objective
To make a practical application of an evaluative computer programme to determine the most effective energy saving measures in 16 existing buildings of the local authority stock.
The aim is a 10% additional saving on previous 20% saving which can be reached through a manual simulation.
There were several staff problems during the project which resulted in considerable delays. The two different EMS were installed in the 16 schools and all necessary changes to the zoning and equipment have been carried out. To ensure that the rolling programme of installation of energy conservation measures could be maintained, measures were generally selected using manual techniques. Computer analysis of all the buildings in the study were carried out. To enable accurate modelling of the buildings, full architectural surveys were carried out.
The original methodology was generally followed; however the complexity of the buildings showed up limitations in the thermal analysis computer program. Considerable effort and time was required for the surveying of the buildings to obtain sufficient data to produce an accurate model. Having obtained this data the program underwent considerable development during the course of the project in order to produce the necessary accurate models.
Another area which was shown to be problematical was the measurement of the fuel usage within the buildings. Attempts were made to measure this at the source using the building management systems; however the metering equipment available at the time was not sufficiently accurate and prone to malfunction. Hence fuel comparisons were made using invoice figures which could not always be accurately related to the period before and after the installation of energy conservation measures.
The socio-technical study highlighted the limited knowledge building users had of the energy values and costs associated with their buildings. In addition it highlighted the complex occupancy patterns and environmental condition criteria required by most of the buildings selected for the study. The study did however make the building users more aware of their surroundings and engendered considerable enthusiasm for the control of energy usage in those schools where direct contact was made.
The selection ofan energy management system to control the environment within a building was found to require careful matching to the individual building's control and heating distribution strategy. In addition thourough commissioning after installation was found to be essential.
From pure analysis of the results, the project failed in its aim to show the predicted 10 % improvement in energy savings over conventional manual selection techniques. The Tas thermal analysis modelling program however proved its usefulness in the comparison of energy conservation measures both in isolation and combination using simple building models. The results showed calculated savings of between 7 % and 10 % per annum for the various measures. These could not be substantiated in practice when applied to the complex buildings used for the study, as the year to year variation in energy consumption of up to 35 % masked the potential saving generated by the application of the energy conservation measures.
For each of the 16 typical "local authority stock" buildings in the group, the demonstration project consists of:
1) Establishing the original situation:
- Architectural features and specifications of the heating systems;
- Mode of occupation and mode of operation of the heating systems;
- Energy consumption levels and the corresponding weather conditions.
2) Devising energy savings:
- Ways of savings energy. For the same (acceptable) investment, the methods
are selected (a) manually and (b) by computer simulation;
- The energy consumption figures, calculated by computer for the original
situation and for the two improved situations (with ways of saving
energy selected manually or by computer) are compared and the
benefit of selecting by computer is thus evaluated.
3) Implementing the ways of saving energy. These are selected manually for
half of the buildings and are selected by computer for the other half.
4) Recording the improved situation:
- Energy consumption levels and the corresponding weather conditions;
- The mode of occupation and the mode of operation of the heating systems.
5) Correcting the measured energy consumption figures to put them on the same
basis as the original energy consumption figures in terms of the weather
conditions and the modes of occupation and heating system operation.
This is done by computer simulation.
6) Establishing the actual energy savings and validating the methods of
selecting the ways of saving energy.
Programme(s)
Topic(s)
Call for proposal
Data not availableFunding Scheme
DEM - Demonstration contractsCoordinator
CM1 1LB CHELMSFORD
United Kingdom