Hello,
We are working on a LEED NC 2009 project in Germany with DES which the thermal plants consist 5 boilers and a cogenerator.
We are thinking to follow the Scandinavian DES protocol to replace Option 2 in the DES v2 guidance. According to 4.1-Equation 1:
PEFdh = ∑Ef,hob(i)*PEFhob(i)+ ∑αh,i*Ef,chp(i)*PEFchp(i) / ∑Qdel,j
The energy inputs in fuel and the delivered heating energy are requested to calculate the total primary energy factor.
The question is, are the energy inputs in fuel (Ef,hob(i), Ef,chp(i)) and the delivered heating energy (∑Qdel,j) the total annual amount or can I take the specific value in kW as planned. So far the DES does not yet exist so we don’t have the annual amounts.
If the total annual amounts shall be used here, then what is the difference between this alternative and the Option 2 in the DES v2, in which the annual energy consumption and the generated energy are also requested to calculate the average heating efficiency.
Any advice is appreciated. Thank you in advance.
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5867 thumbs up
February 4, 2015 - 3:09 pm
The energy inputs and delivered heating energy are the total annual amounts. The designed capacities for equipment in a DES which does not yet exist should not be used because this would not account for part-load operation or staging of multiple pieces of equipment in the DES throughout the annual operation.
The difference between Equation 1 of the Scandinavian DES protocol and the average efficiency of Option 2 of DES v2 is that the Scandinavian DES protocol is based on primary (source) energy and DES v2 is based on site energy (at the DES). The Scandinavian DES protocol also weighs both the primary energy factor (PEF) and CO2 emissions to calculate a performance factor, which is used to calculate the price.
DES v2 includes an option for modeling the entire DES in order to calculate the average efficiency, which addresses your scenario where the DES does not yet exist. I don't see this as an option in the Scandinavian DES protocol, likely because it was designed primarily for large Scandinavian DES networks which already exist. However, GBCI may allow you to apply the modeling methodology from DES v2 to the Scandinavian DES protocol, which you can confirm through a LEED interpretation.
Qian Tang
February 5, 2015 - 3:30 am
Thank you marcus! It is really clearly explained and very helpful information. So we want to follow the DES v2 now, but still try the Scandinavian DES protocol with same modeling methodology from DES v2 as a check and to see whether we can get better results, probably very similar results of these two methods.
Regards