Delivering best value in airconditioning projects
It is very rare for lowest first costs to offer value in its truest sense — Alan Tyson.
ALAN TYSON warns that value engineering should not be confused with cost cutting or trimming the specification as a project progresses.Value engineering at its worst has become a euphemism for cost cutting. At its best it means exactly what it says — designing the system that will deliver exactly what the client requires in terms of comfort at the most competitive first cost and, perhaps more importantly, the optimum whole-life cost. That, of course, should be the common objective of the whole team — designer, supplier and installer — for every project. In an ideal world, at the time of the initial concept and design the designer will sit with the building owner/occupier to define the priorities for the building.
Priorities Whilst no air-conditioning system will be absolutely perfect for a project in all respects, its strengths and weaknesses can always be balanced. There will always be priorities. Are lowest operating costs more important than the potential for partitioning flexibility? Is maximum lettable space more important than ease of maintenance? Indoor air quality is also a major issue, as are environmental impact and compliance with future legislation. One thing is certain — it is very rare for lowest first costs to offer value in its truest sense. Manufacturers know all about value engineering. They have to in order to flourish in today’s competitive world. They invest heavily in designing and producing systems that the market wants at the right price. They have a wealth of knowledge to contribute to the whole value-engineering process. However, too few designers are taking whole life costs seriously. Whilst they pay lip service to energy efficiency, it can be faster and less risky to select the system that has worked well in other projects, going for the ‘one system fits all’ method. Assuming that the equipment supplier is able to offer a selection of systems that could do the job, it makes a lot of sense to look at the computer print outs that modern software can generate on running costs, on the cost implications of heat reclaim, on the choice of a heat-pump system and on the impact that control systems could have. There are now also system-leasing possibilities and maintenance agreements to be considered when calculating the lifetime cost of the system.
Reasonable price It is safe to assume that the building owner does not want air conditioning — he just wants reliable comfort at a reasonable price in the same way as he needs electricity or other utilities. It is tempting to over-design a system to build-in the ‘just-in-case’ factor and the ‘nice-to-have’ capabilities just because they are possible. However, this approach is really the antithesis of ‘value engineering’. Real value comes by removing the ‘bells and whistles’ that add nothing but complexity to the running of the building. Since the vast majority of systems operate at full capacity for only few days of the year, it is more effective to study the part-load performance of chillers for example since this is critical to the overall efficiency of the system. By identifying the priorities, measuring the options against these criteria and using the software available to design various systems and compare running costs, a great deal of engineering value can be added before the tender goes in.
Too late In the worst-case scenario, all too often value engineering happens too late — when the price is too high, perhaps because too much capacity was allowed for or inefficient chillers selected for whatever reason. That is when contractors, without reference to the client’s needs, use value engineering to cut cost from the bottom line, with everybody downstream being asked to reduce margins to levels that cannot support a healthy industry. It also means the client gets an over-engineered job with the corners cut. The best value is not the cheapest first cost.
Specification Cost savings can sometimes best be provided by looking again at the specification, not just the price. Perhaps a more packaged or modular solutions could be selected. Perhaps the equipment that is easiest to install will provide bigger savings than slashing margins ever could. Perhaps by this stage in the project the building user is known and the exact capacity needs are known, enabling re-sizing or energy saving to come into the picture or may be the sheer adaptability of a system can be seen to add value at this point. Maybe the specified heat-recovery option does not make not financial sense and cutting that capability saves more money than recovering heat ever could. Or perhaps there is a heat source in the area that has not been taken into account, and a chiller capable of hear recovery might need to be added for true value engineering to be applied. If an air conditioning manufacturer is not asked these questions they cannot provide the answers. The sooner they are included in the loop the sooner value engineering can be certain to be applied. The manufacturer should be used as a valuable resource with a real contribution to make, rather than being excluded. What is the point of an over-engineered system with over-sophisticated external controls and over-complicated user interface? If the chiller can provide the controls built-in then why not let it? Why put a control system on top of a control system? This is often an area where controls suppliers weave a web of mystery, but talking to the chiller manufacturer early can often remove the need for unnecessary complexity. But that’s probably the topic for another debate.
Alan Tyson is commercial director with Toshiba Carrier UK,, United Technologies House, Guildford Road, Leatherhead, Surrey KT22 9UT.
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