Recently I am dealing with more and more questions when it comes to emission calculation. The following question refers to HBEFA (Handbook of Emission Factors) and I'd like to gather the details here. I hope this info is very helpful for those of you who deal with the Emission Calculation.
Here we go:
And here's my response and the additional info from DEV:When I get HBEFA emission from PTV, the result is something like(I only added the measurement unit) :
{
"hydrocarbons" : 10.980518059922922 - g
"ammonia" : 0.38452199999999975 - g
"carbonDioxide" : 103.73796777864813 - kg
"carbonMonoxide" : 55.04731854349741 - g,
"nitrogenOxides" : 454.27380011806025 - g
"fuelConsumption" : 32.63185594215313 - kg
"benzene" : 0.18342729152359694 - g
"numberOfParticles" : 9.818865050144606E15,
"hydrocarbonsExceptMethane" : 10.717246994539957 - g
"sulphurDioxide" : 0.5219520164427847 - g
"methane" : 0.2636018331649443 - g
"nitrogenDioxide" : 95.397495868253 - g
"particles" : 4.437653087658653 - g
}
I have noticed that most of the emissions are reported in grams or kg. (with the logical exception of numberOfParticles).
My question for you is: Is the carbonDioxide value(the one in kg) - the total value of the other emissions in CO2 equivalents?
There's a difference between the substance "CO2" and the term "CO2e" (=CO2 Aequivalent). The HBEFA standard 3.2 and before return "the mass of CO2 emitted on the route (or segment...)". To gather the total CO2e from a HBEFA 3.2 (or earlier) calculation a user would have to multiply each emitted substances mass with the specific factor also known as Global Warming Potential and then sum up the specific CO2e values.
From HBEFA 4.1 there's also a return value for CO2e but this hasn't been implemented as of today.
And here's the DEV statement:
If you have questions: do not hesitate to respond to the post or approach me 1:1!In HBEFA data, there are 3 values for CO² :
- CO2-total (= carbon dioxide “total”, computed as total CO2 from fuel consumption; see below)
- CO2-rep (= carbon dioxide “reported”, i.e. without the biofuel share in the fuel, see below)
- CO2e (CO2 equivalents)
With the following notes:
- CO2 equivalents contain CO2, CH4 and N2O, i.e. the relevant greenhouse gases from the transport sector, multiplied with their respective 100-year Global Warming Potentials and summed up.
- The CO2 emissions are calculated as “total CO2“ – based on the assumption that the carbon in the fuel is totally oxidised into CO2. In addition, HBEFA 3.1/3.2 also provide “„CO2-rep(orted)“ which considers only the „fossil“ part of the fuel without the biofuel share. This fraction is based on country specific assumptions”
So finally, you are totally right. In xServer2, we only return the CO2-total and CO2-rep values.
The CO2e is new in HBEFA 4.1 and has not been integrated.
Bernd
