Last week, paragraph two, I warned readers about this post, which discusses the impact risks for energy efficiency programs.
When using efficiency impacts for 20-year utility resource planning, nearly all the uncertainty resides beyond the cushy office of the evaluator – in the field. This uncertainty and risk was demonstrated back in July in Drive-by Evaluation. The crux of that post was the uncertainty inherent with installation and operation, compared to risk on paper, which is comparatively very low. For reference, see the chart below where we show the cushy desk review versus reality (site inspected).
Advancing the story in this post, I built a table for gross savings and net savings risks for many programs, shown in the table below.
Net to Gross Follies
But first, let’s review definitions of gross savings, net savings, and net-to-gross.
Gross savings are the savings achieved for a measure, regardless of why it was implemented.
Net savings apply the “why” to the gross savings. We use the term net-to-gross, or NTG, which is net savings divided by gross savings. Net-to-gross values may be assigned as follows for each scenario, in response to each customer quote. I should mention that a lot of NTG indicate customers would do the project anyway. This results in free riders.