Working with
Energy efficiency studies
Large industrial, commercial and institutional facilities use a considerable amount of resources each day. These resources include (but are not limited to):
> Electrical power
> Natural Gas
> Fuel oil
> Water/waste water
Saving on energy and other resources can be considered to be a potential "hidden profit" - the savings to the bottom line are there, but you have to find them first. A good energy/resource efficiency study will not only identify the opportunities but also provide economic justification for the changes necessary to reduce costs. Although conservation of energy and resources, and increased sustainability is desirable, one of the main outcomes of a study is the reduced operational costs. And the changes required must be evaluated against the operation, maintenance, and production of the facility - energy saving opportunities that negatively impact production or operation are not good opportunities.
The recommended method of conducting studies is to look at the energy and resource intensive systems, typically central utilities, HVAC and process/manufacturing equipment. Some typical opportunities include:
> Reduction of compressed air pressure setpoint
> Steam trap maintenance and increased recovery of condensate for steam systems
> Upgrades to distribution systems, such as variable speed pumps, or conversion of 3 way flow control valves to two way valves
> Identifying why the overall system temperature differential in chilled water, heating hot water and cooling towers is significantly lower than original design value
> Evaluation of replacement equipment with higher efficiency
> Recovery and reuse of process water and/or waste water
> Heat recovery and reuse
A great energy/resource study will evaluate not only the individual systems, but their interactions with other systems and components in a holistic manner to optimize potential savings. Then the economics of implementing any recommended opportunities must be evaluated to determine the simple return or ROI for each recommendation, such that the Owner can determine which opportunities to invest in.