As I mentioned in the prior post, the City of Boston is proposing that Boston facilities begin to report their energy use and carbon emissions via a tool created by the Feds called the Energy Star Portfolio Manager (PM).
PM is a web-based tool into which one enters utility consumption and cost data. PM then performs a couple of calculations:
- By looking at your location, the program determines the likely carbon emissions associated with your energy use. For example, there is far less coal-generated power on the East Coast than there is in the Midwest, so the CO2 emissions per kilowatt-hour are corresponding lower thanks to our nuclear, gas-fired and hydro sources.
- By dividing your energy use by your square footage, the program determines an energy density. By comparing the energy density of similar building types (e.g. office building) one can rank them. And if one ranks high enough, one earns the “coveted” Energy Star rating.
First, some disclosure. The full PM program may do waaaay more than mentioned above. I am focusing on what I understand the City to be looking to do with it in this post.
Now, this is the starting point for all sorts of commentary, so bear with me as I jump about explaining the awfulness of this tool.
You will note, first of all, that PM is performing calculations that are so simple that one sort of questions why it’s even put up on the web. Once I know the CO2 emissions per kilowatt-hour (kWh) and per thousand pounds of steam (MLb) in my area, why can’t I just multiply my use by said factors and divide by my square footage?
Similarly, the energy content per kWh and per MLb is well known, so PM is not needed for this, either.
Now, that might sound petulant. If PM does the job, even if it’s simple, then what’s the problem, right? But the fact is that PM is very cumbersome and time consuming to work with, whereas doing the same calculations in a local spreadsheet (or even better, a database!) is quicker and allows for much more flexible reporting. So there’s that. There’s also the fact that, while you can force me to put information into PM, there is no way you could force me to use it to monitor energy performance. So it’s simply wasted time and effort in a world that increasingly values efficiency and performance.
My second beef with PM is its lack of detail. PM does not care about the peak demand of a building. Nor does it care whether you use energy during “on peak” times or “off peak” times. Why does this matter? Well, as usual, a thought experiment can illuminate things quite readily.
Imagine two identically sized manufacturing facilities that consume the same amount of energy each year. Well, according to what I describe above, they will grade out with identical Portfolio Manager scores. However, it is quite possible that one facility has implemented energy savings strategies that have dropped the peak building demand, and that they are operating for more hours (and manufacturing more product) without using more total energy.
So wait a minute.
One manufacturer is creating more product while using the same amount of energy, but it’s Energy Star rating is identical to its less efficient neighbor? How can that be?
Simple. The program is too unsophisticated to detect operational efficiency.
Let me say that again:
The program is too unsophisticated to detect operational efficiency.
Yes, ladies and gentlemen. The Ordinance proposed by the City of Boston will use a measuring tool that literally cannot discern the difference between an efficiently run facility and an inefficiently run facility.
This is the stuff that drives you crazy…
I should really play with PM a bit to truly stress test it. If/when I do so, I will report back.
I may come back and add to my awfulness list. Let’s see how time permits.