Breadth or depth?
There are two types of energy studies: exploratory and investment grade. Exploratory studies answer the question, “what kind of energy savings opportunities do we have in this facility?” These studies provide general guidance on where opportunities may be located, and serve as an excellent starting place for discussions about what the possibilities for energy savings are in a specific facility.
Providing a very different set of information, investment grade studies offer detailed information filled with the necessary specifics to make decisions. Investment grade studies answer the question, “with some confidence, how will this project impact my bottom line?” These studies help in selecting one energy (or non-energy) project or measure alternative over another when money is tight.
Necessary outputs – where are the similarities?
Both types of studies should contain additional, important information. First, they should contain sufficient, but limited, background information on the facility that someone with little or no prior knowledge could understand to digest the recommended measures. This is important because these reports are often read by people, such as accountants or third parties, with little familiarity of the facility being discussed.
Second, they should contain enough information that a design engineer could use them as a basis for their design to end up with the desired results. However, this understates an important point: studies are not design documents and owners should not simply hand them over to contractors. The temptation will be there, but in most cases, this approach leaves savings on the table and costs more than it should.
Necessary outputs – how do they differ?
While some types of studies provide a little of both options, it’s important to understand the differences and what the deliverables look like for each type of study.
For exploratory studies, the primary deliverable is a set of potential energy-saving measures. They should be considering a wide variety of options and providing insights into the facility that operators may not have been aware of. Depending on the rigor of the study, these measures may have low-accuracy, ballpark cost and energy-savings estimates, or high-accuracy, investment-grade cost and energy-savings estimates.
An investment grade study may have only a single energy-saving measure analyzed (or 10+ for more in-depth studies). However, the detail of the anticipated costs and energy-saving measures should be very accurate because they rely on rigorous performance and cost analyses.
What’s the best option?
When little is known about a facility’s energy options, an exploratory study helps lay the groundwork and gives orientation. When details are necessary to make big decisions, an investment grade study can really hit the spot. There will be many cases when both conditions are present, and there are study options for that as well. But each option has its place, so choose wisely based on what is required.