Energy Cost

We too have encountered such results, I am interested to know of any possible alternatives. My understanding is that, for better or worse, LEED makes its measurements in dollars - presumably as a means to show demonstrable economic benefits to its implementation. This "follow the money" approach is either brilliant or fatally flawed depending on your perspective. I for one think it's misleading, as energy savings in terms of BTUs/sf is definable, whereas the cost of the fuel is subject to constant market fluctuations.

LEED uses energy cost because the ASHRAE standard uses energy cost. This is likely to change in the next iteration of LEED. One thing to keep in mind is the difference between site energy and source energy. 1 BTU of electricity at the site typically represents about 3 BTU of fossil fuel used to generate that electricity at the source. Site energy BTUs are not an "apples to apples" comparision - 1 BTU natural gas has lower carbon emissions than 1 BTU electricity, if the the electricity is generated from fossil fuels. In an indirect way, using cost as the metric actually captures this nuance.

We too have this experiance but unfortunately no answer. The intensions in LEED is truly missLEEDing as we can not affect the Baseline Building electricity use, the major factor, I think, to the difference between 47 % and 22 % in your exampel, Michael. In Ashrae handbook it is stated that the calculations can be based on energy cost OR energy performance so maby therefore we can use energy performance in LEED instead of energy cost, Chris??

Nope - it's got to be cost, at least until LEED 2012.

Hans, Stop listening to Henry and grow your horizons. Understanding Primary/Source and Site Energy 2010-07 by Kohta Ueno and John Straube What about using energy costs instead? Some (notably ASHRAE 90.1 and LEED) have considered using the cost of energy as a metric, instead of bothering with site-source conversions, Btus, kWh, etc. First, costs are commonly used in economic analyses, and are what many building owners care about the most. Second, energy costs are actually a rough surrogate for/approximation of source energy. This is part of the reason why ASHRAE Standard 90.1 (the energy efficiency standard for large buildings), uses cost in its “building energy cost method” (which calculates the effectiveness of various energy conservation measures) (Jarnagin, 2010).

If LEED wants to support more environmental energy it should compare CO2 or primary energy energy factors instead of cost. In Sweden we often use district heating which has lower cost than most other fuels in most cases is more environmental. In our DES-systems we use lots of different fuels: waste heat from industries, heat from wasteburning, biofuels from woodwaste, crops etc, sometimes topped up with fossilfuels. (Of course we recycle our waste and often take out boigas, what is left is burned). The cost model is not fair on our District heating systems.

As Chris alluded to above, you may have your wish in the next version of LEED, which is out for public comment.

Hello: We are not experiencing this very same problem. We are projecting an energy consumption savings of over 20%, but a cost savings of only 5% due to the price discrepancies between electricity and natural gas (gas being much cheaper). Just wondering if anyone has requested alternate compliance based on energy consumption savings, in lieu of cost savings. I searched the credit interpretations, but did not find anything.

As Chris said above the metric for calculating savings is cost.