One helpful service the architect can provide the HVAC designer is to avoid placing specialty spaces at remote locations. For example, consider a large storeroom situated at one corner of a floor plan, with the staff office at the far corner of that room. A long duct has to be provided all the way across the unconditioned storeroom. It’s better to situate the office next to areas that are already conditioned so that tempered air can be transported there by a short duct run.
This dilemma may, of course, be solved by providing a wall air conditioner and unit heater, instead of linking to the central system. Both of these devices, however, are usually much less efficient than a central system, so the room is conditioned at a premium. With a little architectural space-planning, this situation can be avoided altogether. Take as another example the steam-distribution system in a small hospital. Steam lines are run to the sterilizers in the operating theater, the laundry, and the kitchen. Assume that these services are all situated in one-half of the building. Then the design team locates an autoclave in the other half, far from the main steam loop. This means a long, small-diameter steam line must be run across a great distance. The constant amount of energy lost to condensation, for the pressured steam to reach the autoclave, can easily be more than the energy used by the
unit itself during occasional use.
This remote steam-use location is a prime target for an energy- conservation project to reduce the energy spent transporting steam to a remote minimal-use site. The autoclave can either be moved to a location nearer the steam loop or, if that isn’t convenient, it can be replaced with an electric point-of-use unit. Even though electric heating is much more costly than steam heating from a nonelectric source, in this special case, the electric device can probably be shown to be more cost-effective. This problematic choice could have been avoided altogether, had the autoclave been placed more carefully in the building during the planning stages, to be closer to the main steam loop.
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Excerpt from Energy Conservation Projects.